DOI: 10.1148/rg.271065065
RadioGraphics 2007;27:173-187
Pathologic and MR Imaging Features of Benign Fibrous Soft-Tissue Tumors in Adults1
Philip A. Dinauer, MD,
Clark J. Brixey, MD,
Joel T. Moncur, MD,
Julie C. Fanburg-Smith, MD and
Mark D. Murphey, MD
1 From the Department of Diagnostic Radiology, Hospital of Saint Raphael, 1450 Chapel St, New Haven, CT 06511 (P.A.D.); Departments of Radiology (C.J.B., M.D.M.) and Pathology (J.T.M.), Walter Reed Army Medical Center, Washington, DC; Departments of Radiologic Pathology (M.D.M.) and Soft Tissue Pathology (J.C.F.), Armed Forces Institute of Pathology, Washington, DC; and Departments of Radiology and Nuclear Medicine, Uniformed Services University of the Health Sciences, Bethesda, Md (P.A.D., M.D.M.). Presented as an education exhibit at the 2005 RSNA Annual Meeting. Received April 17, 2006; revision requested May 1 and received June 7; accepted June 15. All authors have no financial relationships to disclose.
Address correspondence to P.A.D. (e-mail: padinauer{at}yahoo.com).
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Abstract
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Benign fibrous (fibroblastic or myofibroblastic) soft-tissue tumors are a heterogeneous group of fibrous lesions with widely varied anatomic locations, biologic behavior, and pathologic features. The four broad categories of fibrous proliferation are benign fibrous proliferations, fibromatoses, fibrosarcomas, and fibrous proliferations of infancy and childhood. The first two categories include nonaggressive fibroblastic lesions such as nodular fasciitis, as well as fibromatoses that demonstrate more aggressive biologic behavior (eg, desmoid tumors). In adults, fibrous tumors are among the most common soft-tissue lesions encountered in clinical practice. MR imaging can be useful for defining the intrinsic signal characteristics, size, and compartmental extension of these lesions. Histologic features of the tumor also may be depicted on T2-weighted MR images. Hypocellular fibrous tumors with dense collagenous components tend to have lower signal intensity on T2-weighted images than do lesions that are more cellular or that contain greater amounts of extracellular myxoid matrix. When interpreting MR images of soft-tissue masses in adults, radiologists should be aware of the clinical behavior, common sites of occurrence, and histopathologic and imaging features of the common benign fibrous soft-tissue tumors.
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LEARNING OBJECTIVES
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After reading this article and taking the test, the reader will be able to:- Recognize MR imaging characteristics that represent typical histopathologic features of benign fibrous soft-tissue tumors.
- Describe typical anatomic locations of benign fibrous proliferations such as nodular fasciitis and fibromatoses.
- Identify treatment options and assess recurrence risks for benign fibrous proliferations and extraabdominal desmoid tumors.
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Introduction
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Although benign fibrous (fibroblastic, myofibroblastic) soft-tissue tumors vary widely in their biologic behavior, pathologic features, and most common anatomic locations, they can be grouped in the following four broad categories: benign fibrous proliferations, fibromatoses, fibrosarcomas, and fibrous proliferations of infancy and childhood (1). This article is focused on the first two categories, which include nonaggressive fibroblastic lesions such as nodular fasciitis as well as fibromatoses that tend to demonstrate more aggressive, infiltrative growth (eg, desmoid tumors) (Table). In adults, benign fibrous tumors are among the most commonly encountered soft-tissue lesions in clinical practice. In a review of 18,677 benign soft-tissue tumors seen during pathologic consultation over a 10-year period at the Armed Forces Institute of Pathology, nodular fasciitis and fibromatosis were the third and fifth most common lesions, respectively (2).
Benign fibroblastic proliferations include entities such as nodular fasciitis and proliferative fasciitis, which usually are manifested as small (<4 cm) superficial masses. These highly cellular lesions initially tend to grow rapidly and clinically simulate malignant neoplasms. However, they have a self-limited course, rarely recur after excision, and never metastasize (1,3). Other distinct fibroblastic proliferations, such as elastofibromas, fibromas of the tendon sheath, and keloids, are more collagenous and less cellular than is nodular fasciitis. Fibromatoses, which may be broadly divided into superficial and deep forms, typically show more aggressive biologic behavior than do benign fibrous proliferations. Lesions in deep anatomic locations tend to grow more rapidly, reach a larger size (>5 cm), and more frequently recur locally after surgical excision than do superficial lesions.
MR imaging allows accurate assessment of the size and extent of fibrous lesions before biopsy or excision. In addition, MR imaging may be useful for following the treatment response, especially in infiltrative tumors that involve major neurovascular structures and that are treated with adjuvant radiation or chemotherapy. Furthermore, potentially useful histologic information may be represented on T2-weighted images. Hypocellular fibrous tumors with dense collagenous components tend to show lower signal intensity on T2-weighted images than do lesions that are more cellular or that have greater amounts of extracellular myxoid matrix (46). For some fibrous tumors, such as plantar fibromatosis and desmoid tumor, the histologic information that is represented on MR images may influence planning for the timing of surgical treatment. Lesions that are predominantly cellular may be associated with a higher risk of recurrence at the surgical site than are hypocellular, densely collagenous lesions (7). When interpreting MR images of soft-tissue masses in adults, radiologists should be aware of the clinical behavior, common sites of manifestation, and histopathologic and imaging features of the relatively common group of benign fibrous soft-tissue tumors.
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Benign Fibroblastic Proliferations
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Nodular Fasciitis
Nodular fasciitis is a benign proliferation of fibro-blasts and myofibroblasts that may be mistaken for a sarcomatous lesion because of its rapid growth, abundant spindle-shaped cells, and mitotic activity (1). Nodular fasciitis is probably the most common benign mesenchymal lesion that is histopathologically misdiagnosed as sarcoma, with resultant unnecessary or overly aggressive surgical therapy (1). The pathogenesis of nodular fasciitis is poorly understood. Some investigators have described it as a reactive lesion that may originate from trauma, whereas others have described chromosomal abnormalities that are suggestive of a neoplastic origin (8).
Nodular fasciitis most often occurs in patients between 20 and 40 years of age, although children also may be affected. It is typically manifested as a rapidly growing mass. In 46% of cases, it is localized to the upper extremity, particularly the volar aspect of the forearm (Figs 1, 2) (1,9, 10). Other sites of manifestation are the trunk (20%), head and neck (18%), and lower extremities (16%) (1,9,10). Symptoms of tenderness and pain are frequently described at presentation (10). The lesions tend to be small (<4 cm), and most (71%) have a maximal diameter of less than 2 cm (11). Three general subtypes of nodular fasciitis may be identified on the basis of the lesion location (subcutaneous, intramuscular, or fascial) (1,12,13). Dermal and intravascular lesions are rare. Most occurrences of nodular fasciitis are subcutaneous, fascia based, and circumscribed; these lesions may be amenable to biopsy or excision without any need for imaging evaluation. Lesions of the intramuscular subtype, because of their larger size, deeper location, and less defined borders, may mimic soft-tissue malignancies both at clinical evaluation and at imaging (3).

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Figure 1a. Subcutaneous fascia-based nodular fasciitis in the upper arm of a 38-year-old man. (a) Axial T1-weighted image shows a small nodule (arrow) localized to fascia on the lateral surface of the brachialis muscle. The lesion dimensions were 0.8 x 0.3 x 1.1 cm. (b) Photomicrograph (hematoxylineosin [H-E] stain) at low power demonstrates a well-circumscribed myxoid and spindle cell lesion (*) in fascia, centered between subcutaneous fat (A) and skeletal muscle (M).
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Figure 1b. Subcutaneous fascia-based nodular fasciitis in the upper arm of a 38-year-old man. (a) Axial T1-weighted image shows a small nodule (arrow) localized to fascia on the lateral surface of the brachialis muscle. The lesion dimensions were 0.8 x 0.3 x 1.1 cm. (b) Photomicrograph (hematoxylineosin [H-E] stain) at low power demonstrates a well-circumscribed myxoid and spindle cell lesion (*) in fascia, centered between subcutaneous fat (A) and skeletal muscle (M).
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Figure 2a. Fascia-based nodular fasciitis in the forearm of a 34-year-old woman with a clinical history of a palpable, rapidly enlarging mass. (a) Axial T1-weighted image shows a 3-cm mass (arrow) in the fascia along the radial aspect of the forearm. (b) Coronal short inversion time inversion recovery image shows linear extension of the lesion (arrows) superficially along the fascia. Although the lesion has nonspecific high signal intensity, nodular fasciitis should be the primary diagnostic consideration because of the lesions small size and forearm location and the patients age and clinical history.
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Figure 2b. Fascia-based nodular fasciitis in the forearm of a 34-year-old woman with a clinical history of a palpable, rapidly enlarging mass. (a) Axial T1-weighted image shows a 3-cm mass (arrow) in the fascia along the radial aspect of the forearm. (b) Coronal short inversion time inversion recovery image shows linear extension of the lesion (arrows) superficially along the fascia. Although the lesion has nonspecific high signal intensity, nodular fasciitis should be the primary diagnostic consideration because of the lesions small size and forearm location and the patients age and clinical history.
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Nodular fasciitis may be categorized as myxoid, cellular, or fibrous, according to the predominant histologic feature of the lesion (10,12). A relationship between the age of the lesion and the histologic subtype has been suggested, with early-stage lesions containing more cellular or myxoid components and with more mature lesions containing more fibrous components (3,10,14). However, a consistent association between lesion age and pathologic subtype has not been demonstrated (15). The histologic diversity of nodular fasciitis likely accounts for the variable MR imaging appearance of the lesions. The signal in hypercellular lesions appears nearly isointense to that in skeletal muscle on T1-weighted images and hyperintense to that in adipose tissue on T2-weighted images (Fig 3) (4). Highly collagenous lesions have hypointense signal on all MR images. Contrast enhancement is typically diffuse but may be peripheral in lesions with a greater extra-cellular myxoid matrix and central fluid-filled spaces (Fig 4) (12,16). The differential diagnosis at MR imaging includes extraabdominal desmoid tumor, neurofibroma, fibrous histiocytoma, and soft-tissue sarcoma. In the presence of an intramuscular lesion, early myositis ossificans may be considered in the differential diagnosis, as well. The imaging-based diagnosis should be verified with an excisional biopsy. Successful treatment typically consists of marginal excision alone, after which there is a 1% incidence of recurrence (17). However, given the self-limited course of nodular fasciitis, several weeks of observation (after a diagnosis based on the results of percutaneous fine-needle biopsy) also have been advocated (18,19). Spontaneous regression and involution of lesions in response to steroid injections have been reported (20).

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Figure 3a. Fascia-based nodular fasciitis in the proximal forearm of a 44-year-old man. (a) Axial T1-weighted image shows a well-defined 1.1 x 1.4-cm mass (arrow) with signal that is nearly isointense to that of skeletal muscle. The mass is centered on the bicipital aponeurosis and overlies the pronator teres muscle. (b) Axial T2-weighted fat-suppressed fast SE image shows homogeneous high signal intensity in the lesion (arrow). (c) Coronal T1-weighted fat-suppressed image shows diffuse enhancement of the lesion (arrow). (d) Photomicrograph (H-E stain) at intermediate power shows alternating cellularity and foci of myxoid degeneration (M), classic features of nodular fasciitis.
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Figure 3b. Fascia-based nodular fasciitis in the proximal forearm of a 44-year-old man. (a) Axial T1-weighted image shows a well-defined 1.1 x 1.4-cm mass (arrow) with signal that is nearly isointense to that of skeletal muscle. The mass is centered on the bicipital aponeurosis and overlies the pronator teres muscle. (b) Axial T2-weighted fat-suppressed fast SE image shows homogeneous high signal intensity in the lesion (arrow). (c) Coronal T1-weighted fat-suppressed image shows diffuse enhancement of the lesion (arrow). (d) Photomicrograph (H-E stain) at intermediate power shows alternating cellularity and foci of myxoid degeneration (M), classic features of nodular fasciitis.
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Figure 3c. Fascia-based nodular fasciitis in the proximal forearm of a 44-year-old man. (a) Axial T1-weighted image shows a well-defined 1.1 x 1.4-cm mass (arrow) with signal that is nearly isointense to that of skeletal muscle. The mass is centered on the bicipital aponeurosis and overlies the pronator teres muscle. (b) Axial T2-weighted fat-suppressed fast SE image shows homogeneous high signal intensity in the lesion (arrow). (c) Coronal T1-weighted fat-suppressed image shows diffuse enhancement of the lesion (arrow). (d) Photomicrograph (H-E stain) at intermediate power shows alternating cellularity and foci of myxoid degeneration (M), classic features of nodular fasciitis.
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Figure 3d. Fascia-based nodular fasciitis in the proximal forearm of a 44-year-old man. (a) Axial T1-weighted image shows a well-defined 1.1 x 1.4-cm mass (arrow) with signal that is nearly isointense to that of skeletal muscle. The mass is centered on the bicipital aponeurosis and overlies the pronator teres muscle. (b) Axial T2-weighted fat-suppressed fast SE image shows homogeneous high signal intensity in the lesion (arrow). (c) Coronal T1-weighted fat-suppressed image shows diffuse enhancement of the lesion (arrow). (d) Photomicrograph (H-E stain) at intermediate power shows alternating cellularity and foci of myxoid degeneration (M), classic features of nodular fasciitis.
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Figure 4a. Painful intramuscular nodular fasciitis in the upper arm of a 46-year-old woman. (a) Axial T2-weighted image shows a 3 x 3.5-cm hyperintense mass in the medial triceps. The mass has lower signal intensity along its periphery (arrow). (b) Coronal gadolinium-enhanced T1-weighted image shows peripheral enhancement of the lesion, with no appreciable enhancement in the predominantly myxoid center. (c) The nodule was exposed and removed with marginal excision after surgical dissection through the long head of the triceps. (d) Photomicrograph (H-E stain) shows fascia (lower left) with typical myxoid degeneration (M) predominantly in the central portion of the lesion. Note the peripheral parallel vessels at the interface between the fascia and the lesion.
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Figure 4b. Painful intramuscular nodular fasciitis in the upper arm of a 46-year-old woman. (a) Axial T2-weighted image shows a 3 x 3.5-cm hyperintense mass in the medial triceps. The mass has lower signal intensity along its periphery (arrow). (b) Coronal gadolinium-enhanced T1-weighted image shows peripheral enhancement of the lesion, with no appreciable enhancement in the predominantly myxoid center. (c) The nodule was exposed and removed with marginal excision after surgical dissection through the long head of the triceps. (d) Photomicrograph (H-E stain) shows fascia (lower left) with typical myxoid degeneration (M) predominantly in the central portion of the lesion. Note the peripheral parallel vessels at the interface between the fascia and the lesion.
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Figure 4c. Painful intramuscular nodular fasciitis in the upper arm of a 46-year-old woman. (a) Axial T2-weighted image shows a 3 x 3.5-cm hyperintense mass in the medial triceps. The mass has lower signal intensity along its periphery (arrow). (b) Coronal gadolinium-enhanced T1-weighted image shows peripheral enhancement of the lesion, with no appreciable enhancement in the predominantly myxoid center. (c) The nodule was exposed and removed with marginal excision after surgical dissection through the long head of the triceps. (d) Photomicrograph (H-E stain) shows fascia (lower left) with typical myxoid degeneration (M) predominantly in the central portion of the lesion. Note the peripheral parallel vessels at the interface between the fascia and the lesion.
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Figure 4d. Painful intramuscular nodular fasciitis in the upper arm of a 46-year-old woman. (a) Axial T2-weighted image shows a 3 x 3.5-cm hyperintense mass in the medial triceps. The mass has lower signal intensity along its periphery (arrow). (b) Coronal gadolinium-enhanced T1-weighted image shows peripheral enhancement of the lesion, with no appreciable enhancement in the predominantly myxoid center. (c) The nodule was exposed and removed with marginal excision after surgical dissection through the long head of the triceps. (d) Photomicrograph (H-E stain) shows fascia (lower left) with typical myxoid degeneration (M) predominantly in the central portion of the lesion. Note the peripheral parallel vessels at the interface between the fascia and the lesion.
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Proliferative Fasciitis and Proliferative Myositis
Proliferative fasciitis and proliferative myositis are uncommon fibroblastic reactive soft-tissue lesions (2). Proliferative fasciitis is a pseudosarcomatous, benign proliferation of myofibroblasts that is most often seen in patients older than 40 years (mean age, 54 years) (1,21). Large, plump myofibro-blasts with basophilic cytoplasm, which resemble ganglion cells and which are embedded in a fibro-myxoid stroma, are characteristic findings at microscopy (21). Like nodular fasciitis, proliferative fasciitis frequently arises in the subcutaneous tissues of the upper extremities. The lesions typically involve either the subcutaneous tissue or superficial fascia. They grow rapidly in the early stages but usually have a maximal diameter of less than 5 cm at presentation. At histopathologic analysis, they may be mistaken for sarcoma (1,21). Proliferative myositis is the deep intramuscular counterpart of proliferative fasciitis. Proliferative myositis and intramuscular lesions of nodular fasciitis have similar anatomic, pathologic, and clinical features and may be variants of the same fibroblastic disorder (22). The MR imaging appearance of proliferative fasciitis and proliferative myositis has not been well described. Local excision is the treatment of choice, but if the diagnosis is confidently made on the basis of cytologic analysis of a fine-needle aspiration specimen, a short period of observation may be reasonable as well, given the self-limited clinical course and the possibility of spontaneous lesion involution (23).
Fibroma of the Tendon Sheath
Fibroma of the tendon sheath is manifested as a slow-growing lesion in adults between the ages of 20 and 50 years (mean age, 31 years) (24). Men are affected twice as often as women. Typical features include a well-circumscribed lesion with a small diameter (< 3 cm) and a location in the extremities. The upper extremities, particularly the fingers, hands, and wrists, are the site of 82% of lesions (Fig 5) (24,25). Most of the lesions are manifested as painless soft-tissue masses. Although some investigators consider fibroma of the tendon sheath a nonneoplastic reactive lesion, a chromosomal 2;11 translocation abnormality suggestive of a neoplastic basis has been described (26).

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Figure 5a. Fibroma of the tendon sheath in the hand of a 39-year-old woman. (a) Axial T2-weighted fast SE image shows a low-signal-intensity mass on the volar aspect of the thumb (arrow). The lesion has signal isointense to that of skeletal muscle. (b) Axial gadolinium-enhanced fat-suppressed T1-weighted fast SE image shows that the heterogeneously enhanced lesion involves the flexor pollicis longus tendon (arrow), which is anteriorly displaced.
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Figure 5b. Fibroma of the tendon sheath in the hand of a 39-year-old woman. (a) Axial T2-weighted fast SE image shows a low-signal-intensity mass on the volar aspect of the thumb (arrow). The lesion has signal isointense to that of skeletal muscle. (b) Axial gadolinium-enhanced fat-suppressed T1-weighted fast SE image shows that the heterogeneously enhanced lesion involves the flexor pollicis longus tendon (arrow), which is anteriorly displaced.
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With regard to its histologic structure, fibroma of the tendon sheath tends toward hypocellularity, with scattered spindle-shaped myofibroblasts embedded in a dense collagenous stroma with slitlike vascular channels and cleftlike spaces (1,27,28). Early lesions show components of increased cellularity and myxoid change that resemble those in nodular fasciitis (1). However, paucicellular, dense fibrous connective tissue typically predominates. Some investigators believe that fibroma of the tendon sheath and giant cell tumor of the tendon sheath represent the two endpoints of a spectrum of cellular proliferation (29,30). Lesions of the two types are similar in size, location, and gross morphologic features.
Fibroma and giant cell tumor of the tendon sheath occur in similar patient populations and commonly are manifested as painless slow-growing masses in the peripheral extremities, particularly the hands, where they may interfere mechanically with tendon or joint function (3032). Local excision is the treatment of choice for fibroma of the tendon sheath. A recurrence rate as high as 24% has been reported (24).
At MR imaging, attachment of the tumor to a tendon or tendon sheath is obvious in most cases. The tumor typically has signal intensity that is equal to or lower than that of skeletal muscle on T1- and T2-weighted images (Fig 6). In the case series described by Fox et al, 50% of lesions had signal intensity equal to or lower than that of skeletal muscle on T2-weighted images, a finding that likely is attributable to the high quantity of collagen in many of these tumors (33). Areas of increased signal intensity are seen in lesions with components of increased cellularity or myxoid change (33). The contrast enhancement pattern is variable, with some lesions demonstrating no appreciable enhancement, whereas others show moderate to marked enhancement (33). If a fibroma of the tendon sheath has hypointense signal on all MR images, it may have imaging features that overlap with those of the localized type of giant cell tumor of the tendon sheath. Hemosiderin depositiona histopathologic feature of giant cell tumormay help distinguish between the two lesions at MR imaging. Because of hemosiderin deposition, gradient-echo images of a giant cell tumor of the tendon sheath may show a "blooming artifact" of accentuated low signal intensity (34), a feature that is not expected in a fibroma of the tendon sheath.

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Figure 6a. Fibroma of the tendon sheath in the foot of a 26-year-old woman. (a) Short-axis T2-weighted image depicts a mass, dorsal to the third metatarsal bone of the right foot, with signal that is hypointense to that of skeletal muscle. The anatomic location and signal intensity of the lesion are suggestive of a fibroma or giant cell tumor of the tendon sheath. (b) Photomicrograph (H-E stain) at high power shows a well-delineated mass that is hypocellular and contains a dense collagenous matrix that surrounds a slitlike vessel (arrow) and scattered spindle-shaped fibroblasts.
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Figure 6b. Fibroma of the tendon sheath in the foot of a 26-year-old woman. (a) Short-axis T2-weighted image depicts a mass, dorsal to the third metatarsal bone of the right foot, with signal that is hypointense to that of skeletal muscle. The anatomic location and signal intensity of the lesion are suggestive of a fibroma or giant cell tumor of the tendon sheath. (b) Photomicrograph (H-E stain) at high power shows a well-delineated mass that is hypocellular and contains a dense collagenous matrix that surrounds a slitlike vessel (arrow) and scattered spindle-shaped fibroblasts.
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Keloid and Hypertrophic Scar
Keloids and hypertrophic scars are benign fibroblastic proliferations that arise from the dermis (Fig 7). Keloids have morphologic and pathologic features that overlap with those of hypertrophic scars, but they may be distinguished from hypertrophic scars by their growth beyond the margins of an injury site, the presence of keloid collagen, less frequent uptake of stain indicative of smooth muscle actin, and higher recurrence rates (35). Keloids are hypocellular, densely collagenous lesions predominantly composed of type I collagen (1). The abundant collagen accounts for the short T2 relaxation times of keloids. Persons of African and Chinese descent have an increased risk for these fibrous lesions. Keloids most frequently are seen in patients aged 1545 years and commonly involve the face, shoulders, forearms, and hands (1). The lesions may arise in association with trauma, infection, or connective tissue diseases, and they tend to occur where there is increased skin tension. Keloids and hypertrophic scars may produce a mass effect, pruritus, and paresthesia, but they typically are secondary to cosmetic deformities (36). Keloids do not spontaneously regress, and they tend to recur after surgical excision. Therefore, surgery has been combined with topical injection of corticosteroids or postsurgical radiation therapy to decrease recurrence (1).

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Figure 7a. Hypertrophic scar in the foot of a 37-year-old woman. (a, b) Sagittal T1-weighted image (a) and short inversion time inversion recovery image (b) demonstrate an elongated low-signal-intensity mass (*) that has arisen in the skin on the plantar aspect of the foot. (c) Photomicrograph (H-E stain) at low power shows the dense collagenous content of the lesion, which accounts for its low signal intensity in a and b; a disorganized spindled fibroblastic cell proliferation oriented in a predominantly horizontal direction, deep to the epidermis (E); vertically oriented vessels (*); and the absence of thick keloid-like collagenous bands.
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Figure 7b. Hypertrophic scar in the foot of a 37-year-old woman. (a, b) Sagittal T1-weighted image (a) and short inversion time inversion recovery image (b) demonstrate an elongated low-signal-intensity mass (*) that has arisen in the skin on the plantar aspect of the foot. (c) Photomicrograph (H-E stain) at low power shows the dense collagenous content of the lesion, which accounts for its low signal intensity in a and b; a disorganized spindled fibroblastic cell proliferation oriented in a predominantly horizontal direction, deep to the epidermis (E); vertically oriented vessels (*); and the absence of thick keloid-like collagenous bands.
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Figure 7c. Hypertrophic scar in the foot of a 37-year-old woman. (a, b) Sagittal T1-weighted image (a) and short inversion time inversion recovery image (b) demonstrate an elongated low-signal-intensity mass (*) that has arisen in the skin on the plantar aspect of the foot. (c) Photomicrograph (H-E stain) at low power shows the dense collagenous content of the lesion, which accounts for its low signal intensity in a and b; a disorganized spindled fibroblastic cell proliferation oriented in a predominantly horizontal direction, deep to the epidermis (E); vertically oriented vessels (*); and the absence of thick keloid-like collagenous bands.
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Elastofibroma
Elastofibroma is a degenerative or reactive fibrous pseudotumor that is generally considered to result from chronic mechanical irritation (1). However, a genetic predisposition also has been described (37), and the identification of clonal chromosomal changes has led to a suggestion that the lesion may represent a fibroblastic neoplasm (38).
Elastofibroma is a slow-growing lesion that is most frequently encountered in the connective tissue between the posterior chest wall and the inferomedial border of the scapula, usually in patients older than 55 years (mean age, 70 years) (37). Autopsy studies have shown subscapular elastofibromas in 11.2% of men and 24.4% of women older than 55 years (39). Computed tomography of the chest has demonstrated elastofibromas in 2% of patients older than 60 years (40). The incidental detection of elastofibroma with fluorine 18 fluorodeoxyglucose positron emission tomography also has been described (41). Subscapular elastofibromas are bilateral in about 25% of cases (42,43). Extrascapular sites, which are much less common, include regions of the greater trochanter at the hip and the olecranon at the elbow (37). Symptomatic lesions generally have a diameter greater than 5 cm. The most commonly reported clinical symptoms are stiffness (approximately 25% of patients) and pain (10% of patients) (37). Elastofibromas consist of accumulations of collagen and abnormal elastic fibers, with interspersed fat cells and spindle-shaped fibroblasts and myofibroblasts (Fig 8) (1,39). The differential diagnosis of lesions that are relatively hypocellular and contain abundant collagen includes extraabdominal desmoid tumor, as well as neurofibroma and malignant fibrous histiocytoma.

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Figure 8a. Subscapular elastofibroma. (a) Gross specimen resected from an 81-year-old woman shows an admixture of fibrous tissue (white) with fat (yellow). (b) Low-power photomicrograph (H-E stain) demonstrates fibromyxoid stroma with fat infiltration (white) and scattered elastic fibers (bright red).
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Figure 8b. Subscapular elastofibroma. (a) Gross specimen resected from an 81-year-old woman shows an admixture of fibrous tissue (white) with fat (yellow). (b) Low-power photomicrograph (H-E stain) demonstrates fibromyxoid stroma with fat infiltration (white) and scattered elastic fibers (bright red).
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On MR images, elastofibromas are typically well defined, heterogeneous soft-tissue masses with signal intensity similar to that of skeletal muscle and frequently with intermixed linear or curvilinear streaks of fat signal intensity, findings representative of the histologic constituents of the lesion (Fig 9) (44,45). Gadolinium-related contrast enhancement is typically heterogeneous. Given a characteristic lesion location and patient age at presentation, and signal characteristics of elastofibroma, a prospective MR imaging diagnosis often can be made with a high degree of confidence, particularly when bilateral lesions are identified (46,47). Local excision is the treatment of choice for symptomatic lesions. Local recurrence is rare and likely is due to incomplete excision (37). To our knowledge, no reports of malignant transformation exist in the literature (1).

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Figure 9a. Subscapular elastofibroma in a 57-year-old woman. (a) Axial T1-weighted image of the left upper back shows a lenticular mass (arrow), deep to the latissimus dorsi and serratus anterior muscles (arrowhead), that contains hyperintense linear streaks of entrapped fat. (b) T2-weighted fast SE image without fat suppression depicts the lesion (arrow) with signal predominantly isointense to that of skeletal muscle.
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Figure 9b. Subscapular elastofibroma in a 57-year-old woman. (a) Axial T1-weighted image of the left upper back shows a lenticular mass (arrow), deep to the latissimus dorsi and serratus anterior muscles (arrowhead), that contains hyperintense linear streaks of entrapped fat. (b) T2-weighted fast SE image without fat suppression depicts the lesion (arrow) with signal predominantly isointense to that of skeletal muscle.
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Fibromatoses
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Superficial Fibromatosis
Soft-tissue fibromatoses are divided into two major groups: superficial (fascial) and deep (musculoaponeurotic) lesions. Although soft-tissue fibromatoses are benign and have no metastatic potential, their biologic behavior is somewhat aggressivebetween that of benign fibrous proliferations (eg, nodular fasciitis) and fibrosarcoma. Superficial fibromatoses arise from fascia or aponeuroses at palmar, plantar, penile (Peyronie disease), and knuckle pad locations (1,3). At microscopy, the lesions contain spindle-shaped myofibroblastic cells, dense deposits of intercellular collagen fibers, variable amounts of extracellular myxoid matrix, and compressed and elongated vessels (1).
Palmar fibromatosis (Dupuytren disease) is the most common type of superficial fibromatosis. This slow-growing lesion affects the aponeurosis along the volar aspect of the hand, usually in patients older than 30 years (Fig 10) (1). The lesions occur predominantly in men, and approximately 50% of cases occur in bilateral locations (48). The collagenous cords may produce flexion contractures that typically affect flexor tendons of the fourth and fifth fingers (48). Early-stage mitotically active lesions have high signal intensity on T2-weighted images, are predominantly cellular, and have higher recurrence rates (70%) than more mature lesions, which have a higher collagen content (7,49).
MR imaging may be helpful for planning the optimal timing of surgical treatment of palmar fibromatosis, given that mature collagenous lesions with relatively low signal intensity on T2-weighted images may be less likely to locally recur than are more cellular lesions with higher signal intensity on T2-weighted images (5,7).

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Figure 10a. Palmar fibromatosis in a 44-year-old woman. (a) Sagittal T1-weighted image depicts a 1-cm-long fusiform lesion (arrowhead) along the palmar aponeurosis at the level of the distal fifth metacarpal. (b) Axial T2-weighted MR image shows low signal intensity in the lesion (arrowhead), which is superficial to the flexor tendon (arrow). (c) High-power photomicrograph (H-E stain) shows a relatively hypocellular, infiltrative aponeurotic tumor composed of fibroblasts, elongated vessels, and extracellular keloidal collagen (arrows).
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Figure 10b. Palmar fibromatosis in a 44-year-old woman. (a) Sagittal T1-weighted image depicts a 1-cm-long fusiform lesion (arrowhead) along the palmar aponeurosis at the level of the distal fifth metacarpal. (b) Axial T2-weighted MR image shows low signal intensity in the lesion (arrowhead), which is superficial to the flexor tendon (arrow). (c) High-power photomicrograph (H-E stain) shows a relatively hypocellular, infiltrative aponeurotic tumor composed of fibroblasts, elongated vessels, and extracellular keloidal collagen (arrows).
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Figure 10c. Palmar fibromatosis in a 44-year-old woman. (a) Sagittal T1-weighted image depicts a 1-cm-long fusiform lesion (arrowhead) along the palmar aponeurosis at the level of the distal fifth metacarpal. (b) Axial T2-weighted MR image shows low signal intensity in the lesion (arrowhead), which is superficial to the flexor tendon (arrow). (c) High-power photomicrograph (H-E stain) shows a relatively hypocellular, infiltrative aponeurotic tumor composed of fibroblasts, elongated vessels, and extracellular keloidal collagen (arrows).
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Plantar fibromatosis (Ledderhose disease) may affect both children and adults, with bilateral lesions occurring in 20%50% of cases (50). Men are affected twice as often as women, and associated palmar fibromatosis is seen in 10%65% of patients (50). Nodules or masses of plantar fibromatosis are typically located in the middle to medial aspect of the plantar arch and may extend to involve the skin or deep structures of the foot. Although trauma has commonly been considered a possible cause of plantar fibromatosis, the pathogenesis of the lesion is likely multifactorial. Cytogenetic studies have shown chromosomal aberrations of trisomy 8 and trisomy 14 within some plantar lesions (51). The lesions may be symptomatic because of a mass effect or invasion of adjacent muscles or neurovascular structures. At MR imaging, plantar fibromatosis typically has heterogeneous signal intensity, but the signal in the plantar lesions is predominantly isointense or hypointense to that in skeletal muscle on T1- and T2-weighted images (Fig 11) (52). Local excision with a wide margin is the treatment of choice for painful or disabling lesions. In addition, some symptomatic lesions have been treated effectively with an intralesional steroid injection or with postoperative adjuvant radiation therapy (53). However, radiation therapy must be used selectively, as it may increase the risk of posttreatment functional impairment (54).

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Figure 11a. Plantar fibromatosis along the aponeurosis superficial to the flexor digitorum brevis muscle. (a) Short-axis T1-weighted image shows a lesion (arrow) with foci of intermediate signal intensity corresponding to cellular areas and foci of low signal intensity corresponding to collagenous areas (arrowheads). (b) Sagittal short inversion time inversion recovery MR image shows the lesion (large arrow) with heterogeneous signal intensity and linear extension (small arrow) along the plantar aponeurosis (arrowheads). (c) Incision through the plantar surface of the foot reveals a firm, glistening nodule (arrows) of the medial plantar aponeurosis.
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Figure 11b. Plantar fibromatosis along the aponeurosis superficial to the flexor digitorum brevis muscle. (a) Short-axis T1-weighted image shows a lesion (arrow) with foci of intermediate signal intensity corresponding to cellular areas and foci of low signal intensity corresponding to collagenous areas (arrowheads). (b) Sagittal short inversion time inversion recovery MR image shows the lesion (large arrow) with heterogeneous signal intensity and linear extension (small arrow) along the plantar aponeurosis (arrowheads). (c) Incision through the plantar surface of the foot reveals a firm, glistening nodule (arrows) of the medial plantar aponeurosis.
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Figure 11c. Plantar fibromatosis along the aponeurosis superficial to the flexor digitorum brevis muscle. (a) Short-axis T1-weighted image shows a lesion (arrow) with foci of intermediate signal intensity corresponding to cellular areas and foci of low signal intensity corresponding to collagenous areas (arrowheads). (b) Sagittal short inversion time inversion recovery MR image shows the lesion (large arrow) with heterogeneous signal intensity and linear extension (small arrow) along the plantar aponeurosis (arrowheads). (c) Incision through the plantar surface of the foot reveals a firm, glistening nodule (arrows) of the medial plantar aponeurosis.
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Deep Fibromatosis
Deep fibromatoses, which have a fibrotic bandlike or tendonlike consistency, are also known as desmoid tumors (1,55). Desmoid tumors originate from connective tissue in muscle, fascia, or aponeuroses and occur mostly in adults aged 2535 years (1,3,56,57). Genetic differences between superficial and deep lesions have been described, and these differences may account for the often more aggressive behavior of deep lesions (58). Trisomies at chromosomes 8 and 20 have been identified in many cases of deep fibromatosis, and trisomy 8 may be associated with an increased risk for tumor recurrence (59).
Deep fibromatoses are classified according to their intraabdominal, abdominal, or extraabdominal location. The category of intraabdominal fibromatoses includes tumors that arise within the pelvis and mesentery. Although most cases of mesenteric fibromatosis are sporadic, some are associated with familial adenomatous polyposis (Gardner syndrome) (1). Approximately 10% of patients with Gardner syndrome also have fibromatosis, which typically is of the intraabdominal type and which may be associated with mutations of the APC gene on chromosome 5q22 (60,61). These intraabdominal desmoid tumors are usually located in the small-bowel mesentery, may cause bowel obstruction, and frequently recur after attempted surgical resection (61).
Abdominal fibromatosis is a distinct entity that tends to occur in women during pregnancy or within the 1st year after delivery and in women who use oral contraceptives. This pattern of occurrence may indicate that estrogen is a growth factor for the fibroblastic tumors (1,62). The rectus abdominis and internal oblique muscles of the anterior abdominal wall are most frequently affected (Fig 12) (1).

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Figure 12a. Abdominal desmoid tumor in a 38-year-old woman. (a) Axial T2-weighted image shows a large heterogeneous mass (arrow) that contains regions of intermediate to low signal intensity in the abdominal wall on the left side. (b) Sagittal gadolinium-enhanced T1-weighted image shows an enhanced tumor (arrow) that involves fascial layers of the left rectus abdominis muscle. (c) Photograph of the resected gross specimen demonstrates a well-circumscribed mass with a heterogeneous and fibrous "fish flesh" appearance.
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Figure 12b. Abdominal desmoid tumor in a 38-year-old woman. (a) Axial T2-weighted image shows a large heterogeneous mass (arrow) that contains regions of intermediate to low signal intensity in the abdominal wall on the left side. (b) Sagittal gadolinium-enhanced T1-weighted image shows an enhanced tumor (arrow) that involves fascial layers of the left rectus abdominis muscle. (c) Photograph of the resected gross specimen demonstrates a well-circumscribed mass with a heterogeneous and fibrous "fish flesh" appearance.
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Figure 12c. Abdominal desmoid tumor in a 38-year-old woman. (a) Axial T2-weighted image shows a large heterogeneous mass (arrow) that contains regions of intermediate to low signal intensity in the abdominal wall on the left side. (b) Sagittal gadolinium-enhanced T1-weighted image shows an enhanced tumor (arrow) that involves fascial layers of the left rectus abdominis muscle. (c) Photograph of the resected gross specimen demonstrates a well-circumscribed mass with a heterogeneous and fibrous "fish flesh" appearance.
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Extraabdominal fibromatosis most frequently arises between or adjacent to the fasciae and muscles of the shoulder, chest wall, back, thigh, and knee (1,56,57). The aggressively infiltrative tumors usually have a diameter of more than 5 cm at presentation, grow rapidly, and frequently extend along muscle. They are typically solitary lesions, but multiple lesions are seen in up to 15% of cases (63). The most aggressive lesions usually occur in patients younger than 20 years, among whom the local recurrence rate may be as high as 87% (Fig 13) (64).

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Figure 13a. Aggressive fibromatosis in an 18-year-old man. (a) Axial T2-weighted image shows the subcutaneous origin of a relatively cellular tumor (arrow) located posterior to the infraspinatus and deltoid muscles. (b) Sagittal gadolinium-enhanced fat-suppressed T1-weighted image, obtained within 1 year after lesion excision, shows an enhanced and infiltrative recurrent mass with spiculated margins (arrowheads) that extends posterior and inferior to the scapula. Note the deep intra- and intermuscular component (arrow) located between the supraspinatus and subscapularis muscles.
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Figure 13b. Aggressive fibromatosis in an 18-year-old man. (a) Axial T2-weighted image shows the subcutaneous origin of a relatively cellular tumor (arrow) located posterior to the infraspinatus and deltoid muscles. (b) Sagittal gadolinium-enhanced fat-suppressed T1-weighted image, obtained within 1 year after lesion excision, shows an enhanced and infiltrative recurrent mass with spiculated margins (arrowheads) that extends posterior and inferior to the scapula. Note the deep intra- and intermuscular component (arrow) located between the supraspinatus and subscapularis muscles.
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MR imaging, which provides better soft-tissue contrast resolution than do other imaging modalities, allows an accurate evaluation of the relationship between the tumor and surrounding vital structures such as vessels, nerves, and bones. An infiltrative border in the form of a fascial tail is frequently observed (approximately 80% of cases, in our experience) on MR images of deep fibromatosis (Fig 14). Fibromatosis usually has heterogeneous signal intensity that likely reflects the different amounts and variable distribution of spindle-shaped cells, extracellular collagen, and myxoid matrix (55,65). The histologic features of desmoid tumors change over time, and the alterations may be depicted on MR images. Early-stage lesions are more cellular and have a predominantly hyperintense signal on T2-weighted MR images. As desmoid tumors evolve, collagen deposition increases and cellularity and extracellular spaces decrease, with a resultant decrease in signal intensity on T2-weighted images (66). Tumor enhancement with gadolinium-related contrast is typically moderate to marked in intensity (67). On T2-weighted spin-echo (SE) images, the predominant signal intensity of most tumors is intermediate, between that of skeletal muscle and that of subcutaneous fat (6).
In 86% of cases of fibromatosis, T2-weighted images depict hypointense bands that likely correspond to dense conglomerations of collagen bundles seen at histologic analysis (Fig 15) (6). These collagen bundles are not enhanced by contrast material. Such features are suggestive of the correct preoperative diagnosis. However, the MR imagingbased differential diagnosis may include other infiltrative lesions with predominant low signal intensity on T2-weighted images, such as malignant fibrous histiocytoma, fibrosarcoma, densely calcified masses, and giant cell tumor of the tendon sheath.

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Figure 14a. Extraabdominal desmoid tumor in a 46-year-old man with a history of spinal fusion surgery. (a) Axial T2-weighted fast SE image shows a well-circumscribed mass (arrow), centered between the posterior layer of the thoracolumbar fascia and the multifidus muscle, that contains collagenous bands of low signal intensity that are most visible medially. (b) Sagittal T2-weighted fast SE image shows an infiltrative mass between muscle and fascia at the T12-L1 level that extends linearly along the fascia (arrowhead). (c) Photomicrograph (H-E stain) shows a poorly circumscribed proliferation of spindle cells and ectatic blood vessels. The lesion (*) has infiltrated adipose tissue (arrow) and skeletal muscle (M).
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Figure 14b. Extraabdominal desmoid tumor in a 46-year-old man with a history of spinal fusion surgery. (a) Axial T2-weighted fast SE image shows a well-circumscribed mass (arrow), centered between the posterior layer of the thoracolumbar fascia and the multifidus muscle, that contains collagenous bands of low signal intensity that are most visible medially. (b) Sagittal T2-weighted fast SE image shows an infiltrative mass between muscle and fascia at the T12-L1 level that extends linearly along the fascia (arrowhead). (c) Photomicrograph (H-E stain) shows a poorly circumscribed proliferation of spindle cells and ectatic blood vessels. The lesion (*) has infiltrated adipose tissue (arrow) and skeletal muscle (M).
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Figure 14c. Extraabdominal desmoid tumor in a 46-year-old man with a history of spinal fusion surgery. (a) Axial T2-weighted fast SE image shows a well-circumscribed mass (arrow), centered between the posterior layer of the thoracolumbar fascia and the multifidus muscle, that contains collagenous bands of low signal intensity that are most visible medially. (b) Sagittal T2-weighted fast SE image shows an infiltrative mass between muscle and fascia at the T12-L1 level that extends linearly along the fascia (arrowhead). (c) Photomicrograph (H-E stain) shows a poorly circumscribed proliferation of spindle cells and ectatic blood vessels. The lesion (*) has infiltrated adipose tissue (arrow) and skeletal muscle (M).
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Figure 15a. Extraabdominal desmoid tumor in the neck of a 26-year-old woman. (a) Axial T2-weighted fat-suppressed fast SE image shows a predominantly intermuscular mass with prominent low-signal-intensity fibrous bands (arrow) surrounded by cellular regions of higher signal intensity. (b) Sagittal gadolinium-enhanced T1-weighted image shows longitudinal extension of the enhanced tumor (arrows) along the fascia, and nonenhanced fibrous bands (arrowheads). (c) Gross specimen photograph demonstrates the infiltrative border (arrow) of the fibroblastic tumor, with multiple fibrous bands (arrowheads). (d) Photomicrograph (H-E stain) at intermediate power shows bland myofibroblasts parallel to elongated vessels, and keloidal collagen (pink).
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Figure 15b. Extraabdominal desmoid tumor in the neck of a 26-year-old woman. (a) Axial T2-weighted fat-suppressed fast SE image shows a predominantly intermuscular mass with prominent low-signal-intensity fibrous bands (arrow) surrounded by cellular regions of higher signal intensity. (b) Sagittal gadolinium-enhanced T1-weighted image shows longitudinal extension of the enhanced tumor (arrows) along the fascia, and nonenhanced fibrous bands (arrowheads). (c) Gross specimen photograph demonstrates the infiltrative border (arrow) of the fibroblastic tumor, with multiple fibrous bands (arrowheads). (d) Photomicrograph (H-E stain) at intermediate power shows bland myofibroblasts parallel to elongated vessels, and keloidal collagen (pink).
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Figure 15c. Extraabdominal desmoid tumor in the neck of a 26-year-old woman. (a) Axial T2-weighted fat-suppressed fast SE image shows a predominantly intermuscular mass with prominent low-signal-intensity fibrous bands (arrow) surrounded by cellular regions of higher signal intensity. (b) Sagittal gadolinium-enhanced T1-weighted image shows longitudinal extension of the enhanced tumor (arrows) along the fascia, and nonenhanced fibrous bands (arrowheads). (c) Gross specimen photograph demonstrates the infiltrative border (arrow) of the fibroblastic tumor, with multiple fibrous bands (arrowheads). (d) Photomicrograph (H-E stain) at intermediate power shows bland myofibroblasts parallel to elongated vessels, and keloidal collagen (pink).
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Figure 15d. Extraabdominal desmoid tumor in the neck of a 26-year-old woman. (a) Axial T2-weighted fat-suppressed fast SE image shows a predominantly intermuscular mass with prominent low-signal-intensity fibrous bands (arrow) surrounded by cellular regions of higher signal intensity. (b) Sagittal gadolinium-enhanced T1-weighted image shows longitudinal extension of the enhanced tumor (arrows) along the fascia, and nonenhanced fibrous bands (arrowheads). (c) Gross specimen photograph demonstrates the infiltrative border (arrow) of the fibroblastic tumor, with multiple fibrous bands (arrowheads). (d) Photomicrograph (H-E stain) at intermediate power shows bland myofibroblasts parallel to elongated vessels, and keloidal collagen (pink).
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Most deep fibromatoses are managed with surgical excision with a wide margin. Local recurrence rates are relatively high, with approximately 50% of patients older than 20 years experiencing a recurrence after local excision (56,64). Radiation therapy may be effective in patients with inoperable lesions or in those with gross residual disease after surgical debulking (62) and is probably beneficial in reducing the risk of recurrence of resected tumors with histologically positive margins (56,62,68). In addition, there have been anecdotal reports about the use of adjuvant chemotherapy to control nonresectable tumors (62). MR imaging can be useful for determining the response to radiation therapy or chemotherapy. A positive response to treatment, in which the tumor becomes less cellular and more collagenous, is manifested by decreased lesion size and decreased signal intensity on T2-weighted images obtained at follow-up MR imaging (5).
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Conclusions
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Benign fibrous soft-tissue tumors constitute a large, heterogeneous group of lesions. Some of the lesions, such as nodular fasciitis, have a self-limited course, small size, and superficial location and rarely recur after excision. Other lesions, such as extraabdominal desmoid tumor, demonstrate a tendency toward aggressive behavior, large size, and intramuscular extension, and have high local recurrence rates, which may prompt the use of adjuvant therapies in addition to surgery. In patients who undergo adjuvant radiation therapy or chemotherapy, radiologists can play an important role in evaluating the response to treatment by assessing changes in the signal intensity and size of the lesion on T2-weighted images. Variations in the histopathologic features of fibrous tumors, with regard to the amount and distribution of cells and extracellular matrix, are represented in the MR imaging appearance of the lesions, particularly on T2-weighted images. Lesions with a lesser degree of cellularity and increased collagen content show hypointense signal on T2-weighted images. Deep fibromatoses may be depicted with hypointense bands that correspond to collagenous regions seen at histologic analysis. When interpreting MR images of soft-tissue masses in adults, radiologists should be aware of lesion behavior, common sites of occurrence, and the pathologic characteristics that correlate with the MR imaging features of benign fibrous tumors. This knowledge will help determine an appropriate differential diagnosis and guide decision making about patient care.
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Footnotes
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Abbreviations: H-E = hematoxylineosin, SE = spin echo
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References
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|---|
- Weiss SW, Goldblum JR. Enzinger and Weisss soft tissue tumors. 4th ed. St Louis, Mo: Mosby, 2001; 247346.
- Kransdorf MJ. Benign soft-tissue tumors in a large referral population: distribution of diagnoses by age, sex and location. AJR Am J Roentgenol 1995; 164:395402.[Abstract/Free Full Text]
- Kransdorf MJ, Murphey MD. Imaging of soft tissue tumors. Philadelphia, Pa: Saunders, 1997; 143186.
- Meyer CA, Kransdorf MJ, Jelinek JS, Moser RP. MR and CT appearance of nodular fasciitis. J Comput Assist Tomogr 1991;15:276279.[Medline]
- Robbin MR, Murphey MD, Temple HT, Kransdorf MJ, Choi JJ. Imaging of musculoskeletal fibromatosis. RadioGraphics 2001;21:585600.[Abstract/Free Full Text]
- Kransdorf MJ, Jelinek JS, Moser Jr RP, et al. Magnetic resonance appearance of fibromatosis: a report of 14 cases and review of the literature. Skeletal Radiol 1990;19:495499.[Medline]
- Yacoe ME, Bergman AG, Ladd AL, Hellman BH. Dupuytrens contracture: MR imaging findings and correlation between MR signal intensity and cellularity of lesions. AJR Am J Roentgenol 1993; 160:813817.[Abstract/Free Full Text]
- Donner LR, Silva T, Dobin SM. Clonal rearrangement of 15p11.2, 16p11.2, and 16p13.3 in a case of nodular fasciitis: additional evidence favoring nodular fasciitis as a benign neoplasm and not a reactive tumefaction. Cancer Genet Cytogenet 2002;139:138140.[CrossRef][Medline]
- Meister P, Buckman FW, Konrad E. Nodular fasciitis (analysis of 100 cases and review of the literature). Pathol Res Pract 1978;162:133135.[Medline]
- Shimizu S, Hashimoto H, Enjoji M. Nodular fasciitis: an analysis of 250 patients. Pathology 1984; 16:161166.[Medline]
- Bernstein KE, Lattes R. Nodular (pseudosarcomatous) fasciitis, a nonrecurrent lesion: clinicopathologic study of 134 cases. Cancer 1982;49: 16681678.[CrossRef][Medline]
- Wang XL, DeSchepper AMA, Vanhoenacker F, et al. Nodular fasciitis: correlation of MRI findings and histopathology. Skeletal Radiol 2002;31:155161.[CrossRef][Medline]
- Leung LY, Shu SJ, Chan AC, Chan MK, Chan CH. Nodular fasciitis: MRI appearance and literature review. Skeletal Radiol 2002;31:913.[CrossRef][Medline]
- Price EB Jr, Silliphant WM, Shuman R. Nodular fasciitis: a clinicopathologic analysis of 65 cases. Am J Clin Pathol 1961;35:122136.[Medline]
- Chi CC, Kuo TT, Wang SH. Nodular fasciitis: clinical characteristics and preoperative diagnosis. J Formos Med Assoc 2003;102:586589.[Medline]
- Kim ST, Kim HJ, Park SW, Baek CH, Byun HS, Kim YM. Nodular fasciitis in the head and neck: CT and MR imaging findings. AJNR Am J Neuroradiol 2005;26:26172623.[Abstract/Free Full Text]
- Allen PW. Nodular fasciitis. Pathology 1972;4:926.[Medline]
- Wong NL. Fine needle aspiration cytology of pseuodsarcomatous reactive proliferative lesions of soft tissue. Acta Cytol 2002;46:10491055.[Medline]
- Stanley MW, Skoog L, Tani EM, Horwitz CA. Nodular fasciitis: spontaneous resolution following diagnosis by fine-needle aspiration. Diagn Cytopathol 1993;9:322324.[Medline]
- Graham BS, Barrett TL, Goltz RW. Nodular fasciitis: response to intralesional corticosteroids. J Am Acad Dermatol 1999;40:490492.[CrossRef][Medline]
- Chung EB, Enzinger FM. Proliferative fasciitis. Cancer 1975;36:14501458.[CrossRef][Medline]
- Meister P, Konrad EA, Buckmann FW. Nodular fasciitis and proliferative myositis as variants of one disease entity. Invest Cell Pathol 1979;2:277281.[Medline]
- Kato K, Ehara S, Nishida J, Satoh T. Rapid involution of proliferative fasciitis. Skeletal Radiol 2004;33:300302.[CrossRef][Medline]
- Chung EB, Enzinger FM. Fibroma of tendon sheath. Cancer 1979;44:19451954.[CrossRef][Medline]
- Smith PS, Pieterse AS, McClure J. Fibroma of tendon sheath. J Clin Pathol 1982;35:842848.[Abstract/Free Full Text]
- Dal Cin P, Sciot R, De Smet L, Van den Berghe H. Translocation 2;11 in a fibroma of tendon sheath. Histopathology 1998;32:433435.[CrossRef][Medline]
- Humphreys S, McKee PH, Fletcher CD. Fibroma of tendon sheath: a clinicopathologic study. J Cutan Pathol 1986;13:331338.[CrossRef][Medline]
- Lundgren LG, Kindblom LG. Fibroma of tendon sheath: a light and electron-microscopic study of 6 cases. Acta Pathol Microbiol Immunol Scand [A] 1984;92:401409.[Medline]
- Satti MB. Tendon sheath tumours: a pathological study of the relationships between giant cell tumour and fibroma of tendon sheath. Histopathology 1992;20:213220.[Medline]
- Maluf HM, DeYoung BR, Swanson PE, Wick MR. Fibroma and giant cell tumor of tendon sheath: a comparative histological and immuno-histological study. Mod Pathol 1995;8:155159.[Medline]
- Jones FE, Soule EH, Coventry MB. Fibrous xanthoma of synovium (giant cell tumor of tendon sheath, pigmented nodular synovitis): a study of one hundred and eighteen cases. J Bone Joint Surg Am 1969;51:7686.[Abstract/Free Full Text]
- Ushijima M, Hashimoto H, Tsuneyoshi M, Enjoji M. Giant cell tumor of tendon sheath (nodular tenosynovitis): a study of 207 cases to compare the large joint group with the common digit group. Cancer 1986;57:875884.[CrossRef][Medline]
- Fox MG, Kransdorf MJ, Bancroft LW, Peterson JJ, Flemming DJ. MR imaging of fibroma of the tendon sheath. AJR Am J Roentgenol 2003;180: 14491453.[Abstract/Free Full Text]
- Llauger J, Palmer J, Monill JM, Franquet T, Bague S, Roson N. MR imaging of benign soft-tissue masses of the foot and ankle. RadioGraphics 1998; 18:14811498.[Abstract]
- Lee JY, Yang CC, Chao SC, Wong TW. Histopathological differential diagnosis of keloid and hypertrophic scar. Am J Dermatopathol 2004;26: 379384.[CrossRef][Medline]
- Levy DS, Salter MM, Roth RE. Postoperative irradiation in the prevention of keloids. AJR Am J Roentgenol 1976;127:509510.[Abstract]
- Nagamine N, Nohara Y, Ito E. Elastofibroma in Okinawa: a clinicopathologic study of 170 cases. Cancer 1982;50:17941805.[CrossRef][Medline]
- Hisaoka M, Hashimoto H. Elastofibroma: clonal fibrous proliferation with predominant CD34-positive cells. Virchows Arch 2006;448:195199.[CrossRef][Medline]
- Jarvi OH, Lamsimies PH. Subclinical elastofibroma in the scapular region in an autopsy series. Acta Pathol Microbiol Scand [A] 1975;83:87108.[Medline]
- Brandser EA, Goree JC, El-Khoury GY. Elastofibroma dorsi: prevalence in an elderly patient population as revealed by CT. AJR Am J Roentgenol 1998;171:977980.[Abstract/Free Full Text]
- Wasyliw CW, Caride VJ. Incidental detection of bilateral elastofibroma dorsi with F-18 FDG PET/CT. Clin Nucl Med 2005;30:700701.[CrossRef][Medline]
- Kransdorf MJ, Moser RP Jr, Meis JM, Meyer CA. Fat-containing soft-tissue masses of the extremities. RadioGraphics 1991;11:81106.[Abstract]
- Marin ML, Perzin KH, Markowitz AM. Elastofibroma dorsi: benign chest wall tumor. J Thorac Cardiovasc Surg 1989;98:234238.[Abstract]
- Kransdorf MJ, Meis JM, Montgomery E. Elastofibroma: MR and CT appearance with radiologic-pathologic correlation. AJR Am J Roentgenol 1992;159:575579.[Abstract/Free Full Text]
- Massengill AD, Sundaram M, Kathol MH, El-Khoury GY, Buckwalter JH, Wade TP. Elastofibroma dorsi: a radiologic diagnosis. Skeletal Radiol 1993;22:121123.[Medline]
- Naylor MF, Nascimento AG, Sherrick AD, McLeod RA. Elastofibroma dorsi: radiologic findings in 12 patients. AJR Am J Roentgenol 1996; 167:683687.[Abstract/Free Full Text]
- Yu JS, Weis LD, Vaughan LM, Resnick D. MRI of elastofibroma dorsi. J Comput Assist Tomogr 1995;19:601603.[Medline]
- Laskin WB, Weiss SW. Benign fibrous lesions. In: Bogumill GP, Fleeger EJ, eds. Tumors of the hand and upper limb. Edinburgh, Scotland: Churchill Livingstone, 1993; 224243.
- Rombouts JJ, Noel H, Legrain Y, Munting E. Prediction of recurrence in the treatment of Dupuytrens disease: evaluation of a histologic classification. J Hand Surg [Am] 1989;14:644652.[CrossRef][Medline]
- Lee TH, Wapner KL, Hecht PJ. Plantar fibromatosis. J Bone Joint Surg Am 1993;75:10801084.[Free Full Text]
- Breiner JA, Nelson M, Bredthauer BD, Neff JR, Bridge JA. Trisomy 8 and trisomy 14 in plantar fibromatosis. Cancer Genet Cytogenet 1999;108: 176177.[CrossRef][Medline]
- Morrison WB, Schweitzer ME, Wapner KL, Lackman RD. Plantar fibromatosis: a benign aggressive neoplasm with a characteristic appearance on MR imaging. Radiology 1994;193:841845.[Abstract/Free Full Text]
- Seegenschmiedt MH, Attassi M. Radiation therapy for Morbus Ledderhoseindication and clinical results [in German]. Strahlenther Onkol 2003;179:847853.[CrossRef][Medline]
- de Bree E, Zoetmulder FA, Keus RB, Peterse HL, van Coevorden F. Incidence and treatment of recurrent plantar fibromatosis. Am J Surg 2004;187: 3338.[CrossRef][Medline]
- Hartman TE, Berquist TH, Fetsch JF. MR imaging of extraabdominal desmoids: differentiation from other neoplasms. AJR Am J Roentgenol 1992;158:581585.[Abstract/Free Full Text]
- Taylor LJ. Musculoaponeurotic fibromatosis: a report of 28 cases and review of the literature. Clin Orthop Relat Res 1987;224:294302.
- Shields CJ, Winter DC, Kirwan WO, Redmond HP. Desmoid tumors. Eur J Surg Oncol 2001;27: 701706.[CrossRef][Medline]
- Montgomery E, Lee JH, Abraham SC, Wu TT. Superficial fibromatoses are genetically distinct from deep fibromatoses. Mod Pathol 2001;14: 695701.[CrossRef][Medline]
- Fletcher JA, Naeem R, Xiao S, Corson JM. Chromosome aberrations in desmoid tumors: trisomy 8 may be a predictor of recurrence. Cancer Genet Cytogenet 1995;79:139143.[CrossRef][Medline]
- Clark SK, Phillips RKS. Desmoids in familial adenomatous polyposis. Br J Surg 1996;83:14941504.[Medline]
- Jones IT, Jagelman DG, Fazio VW, Lavery IC, Weakley FL, McGannon E. Desmoid tumors in familial polyposis coli. Ann Surg 1986;204:9497.[Medline]
- Pritchard DJ, Nascimento AG, Petersen IA. Local control of extra-abdominal desmoid tumors. J Bone Joint Surg Am 1996;78:848854.[Abstract/Free Full Text]
- Rock MG, Pritchard DJ, Reiman HM, Soule EH, Brewster RC. Extra-abdominal desmoid tumors. J Bone Joint Surg Am 1984;66:13691374.[Abstract/Free Full Text]
- Romero JA, Kim EE, Kim CG, Chung W, Isiklar I. Different biologic features of desmoid tumors in adults and juvenile patients: MR demonstration. J Comput Assist Tomogr 1995;19:782787.[Medline]
- Liu P, Thorner P. MRI of fibromatosis: with pathologic correlation. Pediatr Radiol 1992;22: 587589.[CrossRef][Medline]
- Vandevenne JE, De Schepper AM, De Beuckeleer L, et al. New concepts in understanding evolution of desmoid tumors: MR imaging of 30 lesions. Eur Radiol 1997;7:10131019.[CrossRef][Medline]
- Lee JC, Thomas JM, Phillips S, Fisher C, Moskovic E. Aggressive fibromatosis: MRI features with pathologic correlation. AJR Am J Roentgenol 2006;186:247254.[Abstract/Free Full Text]
- Kuhnen C, Helwing M, Rabstein S, Homann HH, Muller KM. Desmoid-type fibromatosis (aggressive fibromatosis) [in German]. Pathologe 2005; 26:117126.[CrossRef][Medline]
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