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Breast Reconstruction with a Transverse Rectus Abdominis Myocutaneous Flap: Spectrum of Normal and Abnormal MR Imaging Findings¹

¹ From the Departments of Radiology (R.K.D., M.A.R., S.G.O.) and Pathology (C.M.), Hospital of the University of Pennsylvania, 3400 Spruce St, Philadelphia, PA 19104. Received November 28, 2003; revision requested February 6, 2004, and received March 23; accepted March 25. All authors have no financial relationships to disclose. Address correspondence to M.A.R. (e-mail: rosen@oasis.rad.upenn.edu).

	Abstract

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The authors retrospectively reviewed their clinical database for cases of breast magnetic resonance (MR) imaging performed in women who had undergone breast reconstruction with a transverse rectus abdominis myocutaneous (TRAM) flap. Patient histories, MR imaging results, and, when available, biopsy results were reviewed. During a 4-year period, 24 neobreasts were imaged in 22 women who had undergone TRAM flap reconstruction after mastectomy. In most of the cases (64%), the indication for MR imaging was a palpable abnormality or pain. In four of 24 cases (17%), recurrent breast cancer was detected. These cases consisted of a local chest wall tumor (n = 2), an infiltrating chest wall tumor (n = 1), and axillary nodal recurrence (n = 1). In all four cases, MR imaging demonstrated a suspicious lesion or abnormality. In 11 of 24 cases (46%), benign findings only were demonstrated. These consisted of localized or diffuse skin thickening, fibrosis, fat necrosis, and seroma. In nine of 24 cases (38%), no pathologic abnormality was identified. MR imaging is useful in detection of locally recurrent tumor in patients who have undergone breast reconstruction with a TRAM flap. MR imaging allows differentiation between benign and malignant findings in patients with palpable abnormalities or pain after TRAM flap reconstruction.

© RSNA, 2004

Index Terms: Breast, surgery, 00.4545 • Grafts, 00.4545

	LEARNING OBJECTIVES FOR TEST 3

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After reading this article and taking the test, the reader will be able to:

• Discuss the surgical techniques used in breast reconstruction with both pedicled and free TRAM flaps.
  
• Describe the normal MR imaging appearance of the breast after reconstruction with a TRAM flap.
  
• Identify the MR imaging features of benign sequelae and malignant disease after breast reconstruction with a TRAM flap.
  

	Introduction

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Transplantation of a transverse rectus abdominis myocutaneous (TRAM) flap is a commonly used surgical procedure for breast reconstruction following mastectomy. In this procedure, an autologous myocutaneous flap consisting of abdominal skin, subcutaneous fat, the rectus abdominis muscle, and adjoining vasculature is used for reconstruction of the breast following mastectomy. Since the description of this procedure by Hartrampf et al (1) in 1982, numerous refinements of the basic technique have been developed, which include the pedicled, free, and delayed flap reconstruction (2). The mammographic and computed tomographic (CT) characteristics of normal and abnormal TRAM flap reconstructions have been previously reported in the literature (3,4).

Understanding the expected anatomic appearance of the breast subsequent to TRAM flap reconstruction is critical in the interpretation of magnetic resonance (MR) imaging examinations following surgery. We therefore sought to investigate the normal MR imaging characteristics of TRAM flap reconstruction, focusing on the anatomic relationship between the reconstructed myocutaneous flap and the adjacent chest wall. In addition, we assessed the MR imaging appearance of various benign and malignant findings in the TRAM flap reconstructed breast.

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Surgical Anatomy and Technique
In the TRAM flap technique, the rectus abdominis muscle must be harvested along with the subcutaneous soft tissue to ensure the preservation of the perforating vessels that supply the abdominal skin and subcutaneous fat. The rectus abdominis muscle has a dual blood supply, which includes the superior and inferior epigastric vessels. The blood supply via the superior epigastric artery is less robust than its inferior counterpart, as it is attenuated along its course by multiple tendinous inscriptions (2).

The two major technical variants of the TRAM flap procedure include the pedicled flap (Fig 1) and microsurgical free flap (Fig 2) reconstructions. The microsurgical technique uses the more robust inferior epigastric artery and vein and is preferred in patients with relative risk factors for atherosclerosis including obesity, diabetes mellitus, smoking, and cardiovascular disease, as well as in those patients who have undergone prior abdominal surgery (2). At our institution, pedicled TRAM flaps are more commonly used.

View larger version (51K): [in this window] [in a new window] [Download PPT slide]   Figure 1a.  Pedicled TRAM flaps. Drawings show the surgical technique used for breast reconstruction with unilateral (a) and bilateral (b) pedicled TRAM flaps. The abdominal soft tissue is tunneled subcutaneously and placed in the mastectomy bed. Mesh reinforcement may be used in the abdominal defect.

View larger version (53K): [in this window] [in a new window] [Download PPT slide]   Figure 1b.  Pedicled TRAM flaps. Drawings show the surgical technique used for breast reconstruction with unilateral (a) and bilateral (b) pedicled TRAM flaps. The abdominal soft tissue is tunneled subcutaneously and placed in the mastectomy bed. Mesh reinforcement may be used in the abdominal defect.

View larger version (56K): [in this window] [in a new window] [Download PPT slide]   Figure 2.  Microsurgical free TRAM flap. Drawing shows the surgical technique used for breast reconstruction with a microvascular free TRAM flap, which is based on the inferior epigastric artery. Note that less of the rectus abdominis muscle is harvested.

The free TRAM flap derives its blood supply from the inferior epigastric artery and vein. These vessels are ligated and microsurgically re-anastomosed in the chest to either the thoracodorsal, subscapular, or internal mammary artery and vein. When the procedure is performed in conjunction with an axillary lymph node dissection, the thoracodorsal vessels are used as recipient vessels, as they are already exposed. Compared with the pedicled flap, the free flap requires a smaller amount of rectus abdominis muscle, resulting in a decreased prevalence of abdominal wall hernia (6).

TRAM flap reconstructions may be performed either at the time of mastectomy or as a subsequent procedure. Postoperative complications include total flap necrosis (0.3%), partial flap loss (2%–6%), fat necrosis (15%), and abdominal wall hernias (1.3%) (2). Some authors describe a lower complication rate with microvascular flaps (6), although this is not universally accepted. Skin flap necrosis is seen more commonly in smokers compared to nonsmokers (7). Radiation treatment has also been associated with an increased complication rate, and the timing of reconstruction in patients who require radiation therapy is controversial. Tran et al (8) demonstrated an increased rate of delayed flap complications in patients who underwent reconstruction prior to radiation therapy.

MR Imaging of the Postoperative Breast
MR imaging has been demonstrated to be extremely useful for demonstrating clinically occult breast cancer (9) and in the identification of unsuspected multifocal cancer (10). It is often superior to clinical examination and mammography for determining the extent of locally advanced cancer. MR imaging is also used in the evaluation of the postoperative breast, as distortion of normal breast architecture can confound the physical examination and the mammographic assessment of the breast. This leads to difficulty in distinguishing between normal postsurgical changes and locally recurrent breast cancer. Radiation-induced changes, including fibrosis and skin thickening, further complicate clinical evaluation in these patients.

MR imaging has been used successfully to differentiate between benign postoperative findings and recurrent breast cancer (11,12). The most important factor in the ability of MR imaging to allow differentiation between neoplasia and posttreatment changes is the integration of lesion morphology and enhancement kinetics (13) following administration of gadolinium contrast material. Breast cancers, whether primary or recurrent, will typically demonstrate early and rapid contrast enhancement kinetics, often with delayed washout. Benign postoperative changes, such as fibrosis or fat necrosis, will generally demonstrate more gradual uptake of contrast material (14). The specificity of MR imaging in the irradiated breast may vary, with more prominent enhancement present for up to 1 year following radiation treatment (15).

	Methods

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The study protocol was approved by the local institutional review board.

Review of Records
Using a keyword search, we reviewed our clinical database for breast or chest MR imaging examinations in patients with TRAM flap reconstruction. A total of 30 such examinations in 22 patients were performed between April 1998 and March 2002. The results of these studies were retrospectively reviewed and assessed for the morphology of the reconstructed breast, as well as for the presence of focal or diffuse abnormalities. The patient histories, radiologic reports, and when appropriate pathologic reports were reviewed. The clinical indication for imaging, as indicated in the radiologic report, was noted.

MR Imaging
MR imaging was performed on a 1.5-T system (Signa; GE Medical Systems, Milwaukee, Wis) with either a dedicated breast coil (USA Instruments, Aurora, Ohio) or with a torso array coil for selected cases involving a more extensive area of clinical concern (eg, chest wall or brachial plexus). The breast MR imaging examination included the following sequences: axial localizing, sagittal T1-weighted spin-echo, sagittal T2-weighted fast spin-echo with fat saturation, and sagittal three-dimensional (3D) fat-saturated spoiled gradient-echo (GRE). The latter was performed prior to and twice following administration of gadolinium contrast material (0.1 mmol/kg). Larger field of view imaging in the axial plane was occasionally performed in selected cases where additional imaging of the chest wall was required.

The following imaging parameters were used: For the T1-weighted spin-echo sequence, repetition time msec/echo time msec = 300–600/15–30, matrix = 256 x 192, section thickness = 3 mm with 1-mm spacing. For the T2-weighted fast spin-echo sequence, 3000–6000/80–100, matrix = 256 x 192, section thickness = 3 mm with 1-mm spacing. For the contrast material–enhanced T1-weighted 3D GRE sequence, 18–20/2–3, flip angle = 35°, matrix = 512 x 256, 28 partitions with a section thickness of 2.0–3.4 mm. Imaging time for the 3D GRE sequence was approximately 90 seconds.

	Results

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A total of 22 women and 24 breasts were imaged in the study period. Two of the patients had bilateral TRAM flap reconstruction and had both breasts imaged. Six women also underwent follow-up MR imaging during the study period. The mean age of the patients was 45 years (range, 31–57 years). The interval between imaging and surgery averaged 42 months (range, 7–120 months). The indications for examination included pain (n = 3), palpable abnormality (n = 11), axillary lymphadenopathy (n = 2), and screening (n = 1) (Table 1). The reason for the examination could not be determined in five patients.

MR imaging demonstrated a normal postoperative appearance in nine of 24 cases (38%). Benign abnormalities only were demonstrated in 11 of 24 cases (46%) and included skin thickening (n = 1), extensive fibrosis or scarring (n = 5), seroma (n = 3), and fat necrosis (n = 3). These MR imaging findings are summarized in Table 2. There was one patient who had two benign findings, whereas another patient had a single benign finding as well as tumor recurrence. In four of 24 cases (17%), tumor recurrence was demonstrated. This included three cases of local tumor recurrence and one case of isolated axillary nodal recurrence.

In all cases with suspicious MR imaging findings, tumor was confirmed histologically. In two additional patients, histologic proof of benignity was obtained subsequent to the MR imaging examination. All of the biopsies were performed for palpable abnormalities without imaging guidance. Of the remaining patients with normal or benign findings, eight of 16 underwent radiologic and/or clinical follow-up of at least 9 months duration (range, 9–53 months; median, 26 months). In one of these patients, a benign-appearing axillary lymph node was shown to harbor recurrent disease 14 months following the MR imaging examination. For eight of the 16 patients with normal or benign findings, no follow-up results were available.

Normal MR Imaging Appearance of a TRAM Flap
The most familiar changes of TRAM flap reconstruction include the replacement of the normal glandular tissue of the breast with lower abdominal fat and the presence of atrophied rectus abdominis muscle along the anterior chest wall (Fig 3). A thin curvilinear line that parallels the breast contour is often recognized and represents the epithelial layer of the lower abdominal tissue. The fatty signal intensity anterior to the epithelial layer represents the native chest wall, whereas that deep to it represents abdominal wall fat (Fig 3b, 3c). These findings are similar to those previously described in both mammographic and CT studies of TRAM flaps (4).

View larger version (67K): [in this window] [in a new window] [Download PPT slide]   Figure 3a.  Normal appearance of a TRAM flap at MR imaging. (a) Axial T1-weighted image of both breasts shows complete fatty composition of the left breast. For comparison, note the normal glandular tissue in the right breast. (b) Sagittal T1-weighted image of the TRAM flap shows the atrophied rectus abdominis muscle anterior to the chest wall (*). The denuded dermal layer of the abdominal tissue (arrows) is seen parallel to the skin of the breast. (c) Corresponding mediolateral oblique mammogram shows the muscular pedicle (*).

View larger version (146K): [in this window] [in a new window] [Download PPT slide]   Figure 3b.  Normal appearance of a TRAM flap at MR imaging. (a) Axial T1-weighted image of both breasts shows complete fatty composition of the left breast. For comparison, note the normal glandular tissue in the right breast. (b) Sagittal T1-weighted image of the TRAM flap shows the atrophied rectus abdominis muscle anterior to the chest wall (*). The denuded dermal layer of the abdominal tissue (arrows) is seen parallel to the skin of the breast. (c) Corresponding mediolateral oblique mammogram shows the muscular pedicle (*).

View larger version (93K): [in this window] [in a new window] [Download PPT slide]   Figure 3c.  Normal appearance of a TRAM flap at MR imaging. (a) Axial T1-weighted image of both breasts shows complete fatty composition of the left breast. For comparison, note the normal glandular tissue in the right breast. (b) Sagittal T1-weighted image of the TRAM flap shows the atrophied rectus abdominis muscle anterior to the chest wall (*). The denuded dermal layer of the abdominal tissue (arrows) is seen parallel to the skin of the breast. (c) Corresponding mediolateral oblique mammogram shows the muscular pedicle (*).

At MR imaging, benign skin thickening can be identified as a diffuse band of tissue that is dark on T1-weighted images and bright on T2-weighted images (Fig 4). These findings are nonspecific, and tumor infiltration in inflammatory carcinoma can manifest similarly. However, in inflammatory cancer, there is more marked skin enhancement, with underlying tumor enhancement in either a septal or solid pattern (16). Skin enhancement following radiation therapy is more uniform and usually not as intense.

View larger version (140K): [in this window] [in a new window] [Download PPT slide]   Figure 4a.  Skin thickening in a 41-year-old woman after TRAM flap reconstruction and radiation therapy. Sagittal T1-weighted (a) and T2-weighted (b) images of the reconstructed breast show radiation-induced skin thickening (large arrow), which appears as increased signal intensity in the dermal layer on the T2-weighted image (b). Note the fat necrosis in the superior breast (small arrow).

View larger version (122K): [in this window] [in a new window] [Download PPT slide]   Figure 4b.  Skin thickening in a 41-year-old woman after TRAM flap reconstruction and radiation therapy. Sagittal T1-weighted (a) and T2-weighted (b) images of the reconstructed breast show radiation-induced skin thickening (large arrow), which appears as increased signal intensity in the dermal layer on the T2-weighted image (b). Note the fat necrosis in the superior breast (small arrow).

In our series, five of 24 cases (21%) demonstrated postoperative seromas or hematomas 17–22 months (mean, 19.5 months) following breast reconstruction. Figure 5 demonstrates a patient 17 months following reconstruction with a large fluid collection in the posterior breast containing a fluid-hematocrit level.

View larger version (132K): [in this window] [in a new window] [Download PPT slide]   Figure 5a.  Seroma in a 45-year-old woman with pain after TRAM flap reconstruction. Sagittal T1-weighted (a) and T2-weighted (b) images of the reconstructed breast show a large fluid collection containing a fluid-fluid level in the lateral breast. Note that the patient was imaged in the prone position.

View larger version (109K): [in this window] [in a new window] [Download PPT slide]   Figure 5b.  Seroma in a 45-year-old woman with pain after TRAM flap reconstruction. Sagittal T1-weighted (a) and T2-weighted (b) images of the reconstructed breast show a large fluid collection containing a fluid-fluid level in the lateral breast. Note that the patient was imaged in the prone position.

At MR imaging, post–radiation therapy fibrosis often displays low signal intensity on T2-weighted images, whereas tumor recurrence is generally isointense or slightly hyperintense to surrounding breast parenchyma (17). However, overlap in signal intensity characteristics exists between both entities (18).

In general, fibrosis can be differentiated from tumor by the degree and kinetics of contrast enhancement. Fibrosis is characterized by no enhancement or low-level enhancement that gradually increases with time. Tumors exhibit more rapid and pronounced tissue enhancement, often with washout kinetics at delayed imaging (18). However, as previously mentioned, false-positive results may arise in the early postoperative period and up to 12 months following radiation treatment due to the presence of enhancing granulation tissue (19).

Figure 6 demonstrates findings compatible with scarring in a patient 76 months following surgery. An irregular mass with low signal intensity on T2-weighted images is seen in the periphery of the reconstructed breast. After administration of gadolinium contrast material, minimal delayed enhancement is seen.

View larger version (126K): [in this window] [in a new window] [Download PPT slide]   Figure 6a.  Fibrosis after TRAM flap reconstruction. Sagittal T1-weighted (a), T2-weighted (b), and delayed gadolinium-enhanced 3D subtraction GRE T1-weighted (c) images of the reconstructed breast show a spiculated mass (arrow) in the posterior breast. The mass demonstrates intermediate signal intensity on the T1-weighted image (a), low signal intensity on the T2-weighted image (b), and minimal delayed enhancement on the gadolinium-enhanced image (c).

View larger version (132K): [in this window] [in a new window] [Download PPT slide]   Figure 6b.  Fibrosis after TRAM flap reconstruction. Sagittal T1-weighted (a), T2-weighted (b), and delayed gadolinium-enhanced 3D subtraction GRE T1-weighted (c) images of the reconstructed breast show a spiculated mass (arrow) in the posterior breast. The mass demonstrates intermediate signal intensity on the T1-weighted image (a), low signal intensity on the T2-weighted image (b), and minimal delayed enhancement on the gadolinium-enhanced image (c).

View larger version (127K): [in this window] [in a new window] [Download PPT slide]   Figure 6c.  Fibrosis after TRAM flap reconstruction. Sagittal T1-weighted (a), T2-weighted (b), and delayed gadolinium-enhanced 3D subtraction GRE T1-weighted (c) images of the reconstructed breast show a spiculated mass (arrow) in the posterior breast. The mass demonstrates intermediate signal intensity on the T1-weighted image (a), low signal intensity on the T2-weighted image (b), and minimal delayed enhancement on the gadolinium-enhanced image (c).

At MR imaging, fat necrosis is characterized by a fatty signal intensity mass, often containing a fat-fluid level that exhibits variable enhancement following administration of gadolinium contrast material (20). Other MR imaging appearances of fat necrosis include a solid irregular mass, with or without a central area of fat intensity. Enhancement of fat necrosis is common but is usually confined to the extreme periphery of the lesion. However, intense solid-appearing enhancement can be seen in fat necrosis, simulating the appearance of tumor recurrence on fat-suppressed images (21,22). The presence of central fat signal intensity is the key to differentiating fat necrosis from tumor recurrence, as breast cancers do not contain central fat.

Fat necrosis is often palpable, manifesting as a firm mass at physical examination. In all three of our patients whose MR imaging findings suggested the diagnosis of fat necrosis, a palpable abnormality was the presenting finding. These cases occurred 19–52 months (mean, 39 months) following reconstruction. Figure 7 demonstrates the MR imaging and mammographic findings in a patient 19 months following TRAM flap reconstruction with both fat necrosis and a postoperative seroma.

View larger version (146K): [in this window] [in a new window] [Download PPT slide]   Figure 7a.  Fat necrosis and seroma in a 57-year-old woman with a palpable abnormality after TRAM flap reconstruction. (a) Sagittal T1-weighted image shows a high-signal-intensity lobulated mass in the upper breast (*). (b) Sagittal T2-weighted image shows that the mass is hypointense (*). A portion of a complex seroma posterior to the mass is also seen (arrow). (c) Sagittal gadolinium-enhanced 3D subtraction GRE image shows moderate peripheral enhancement of the mass (arrows). These findings are compatible with fat necrosis. (d, e) Corresponding mediolateral oblique (d) and craniocaudal (e) mammograms show that the mass is in the upper outer breast and is ovoid with central lucency (arrow). * = muscular pedicle.

View larger version (136K): [in this window] [in a new window] [Download PPT slide]   Figure 7b.  Fat necrosis and seroma in a 57-year-old woman with a palpable abnormality after TRAM flap reconstruction. (a) Sagittal T1-weighted image shows a high-signal-intensity lobulated mass in the upper breast (*). (b) Sagittal T2-weighted image shows that the mass is hypointense (*). A portion of a complex seroma posterior to the mass is also seen (arrow). (c) Sagittal gadolinium-enhanced 3D subtraction GRE image shows moderate peripheral enhancement of the mass (arrows). These findings are compatible with fat necrosis. (d, e) Corresponding mediolateral oblique (d) and craniocaudal (e) mammograms show that the mass is in the upper outer breast and is ovoid with central lucency (arrow). * = muscular pedicle.

View larger version (142K): [in this window] [in a new window] [Download PPT slide]   Figure 7c.  Fat necrosis and seroma in a 57-year-old woman with a palpable abnormality after TRAM flap reconstruction. (a) Sagittal T1-weighted image shows a high-signal-intensity lobulated mass in the upper breast (*). (b) Sagittal T2-weighted image shows that the mass is hypointense (*). A portion of a complex seroma posterior to the mass is also seen (arrow). (c) Sagittal gadolinium-enhanced 3D subtraction GRE image shows moderate peripheral enhancement of the mass (arrows). These findings are compatible with fat necrosis. (d, e) Corresponding mediolateral oblique (d) and craniocaudal (e) mammograms show that the mass is in the upper outer breast and is ovoid with central lucency (arrow). * = muscular pedicle.

View larger version (60K): [in this window] [in a new window] [Download PPT slide]   Figure 7d.  Fat necrosis and seroma in a 57-year-old woman with a palpable abnormality after TRAM flap reconstruction. (a) Sagittal T1-weighted image shows a high-signal-intensity lobulated mass in the upper breast (*). (b) Sagittal T2-weighted image shows that the mass is hypointense (*). A portion of a complex seroma posterior to the mass is also seen (arrow). (c) Sagittal gadolinium-enhanced 3D subtraction GRE image shows moderate peripheral enhancement of the mass (arrows). These findings are compatible with fat necrosis. (d, e) Corresponding mediolateral oblique (d) and craniocaudal (e) mammograms show that the mass is in the upper outer breast and is ovoid with central lucency (arrow). * = muscular pedicle.

View larger version (78K): [in this window] [in a new window] [Download PPT slide]   Figure 7e.  Fat necrosis and seroma in a 57-year-old woman with a palpable abnormality after TRAM flap reconstruction. (a) Sagittal T1-weighted image shows a high-signal-intensity lobulated mass in the upper breast (*). (b) Sagittal T2-weighted image shows that the mass is hypointense (*). A portion of a complex seroma posterior to the mass is also seen (arrow). (c) Sagittal gadolinium-enhanced 3D subtraction GRE image shows moderate peripheral enhancement of the mass (arrows). These findings are compatible with fat necrosis. (d, e) Corresponding mediolateral oblique (d) and craniocaudal (e) mammograms show that the mass is in the upper outer breast and is ovoid with central lucency (arrow). * = muscular pedicle.

View larger version (123K): [in this window] [in a new window] [Download PPT slide]   Figure 8a.  Local recurrence in a 31-year-old woman with a palpable abnormality after bilateral TRAM flap reconstruction. Sagittal T1-weighted (a), gadolinium-enhanced fat-saturated GRE T1-weighted (b), and subtraction (c) images of the reconstructed breast show a round mass just superior to the inframammary crease. The mass demonstrates solid enhancement on the gadolinium-enhanced image (arrow in b). Biopsy revealed poorly differentiated intraductal carcinoma.

View larger version (124K): [in this window] [in a new window] [Download PPT slide]   Figure 8b.  Local recurrence in a 31-year-old woman with a palpable abnormality after bilateral TRAM flap reconstruction. Sagittal T1-weighted (a), gadolinium-enhanced fat-saturated GRE T1-weighted (b), and subtraction (c) images of the reconstructed breast show a round mass just superior to the inframammary crease. The mass demonstrates solid enhancement on the gadolinium-enhanced image (arrow in b). Biopsy revealed poorly differentiated intraductal carcinoma.

View larger version (142K): [in this window] [in a new window] [Download PPT slide]   Figure 8c.  Local recurrence in a 31-year-old woman with a palpable abnormality after bilateral TRAM flap reconstruction. Sagittal T1-weighted (a), gadolinium-enhanced fat-saturated GRE T1-weighted (b), and subtraction (c) images of the reconstructed breast show a round mass just superior to the inframammary crease. The mass demonstrates solid enhancement on the gadolinium-enhanced image (arrow in b). Biopsy revealed poorly differentiated intraductal carcinoma.

View larger version (109K): [in this window] [in a new window] [Download PPT slide]   Figure 9a.  Nodal recurrence in a 50-year-old woman with an axillary mass after TRAM flap reconstruction. Axial T1-weighted (a), axial T2-weighted (b), and sagittal T2-weighted (c) images of the reconstructed breast show enlarged level I and II axillary lymph nodes (arrows). Biopsy of the axillary nodes revealed moderately differentiated infiltrating ductal carcinoma. m in a = pectoralis muscle.

View larger version (135K): [in this window] [in a new window] [Download PPT slide]   Figure 9b.  Nodal recurrence in a 50-year-old woman with an axillary mass after TRAM flap reconstruction. Axial T1-weighted (a), axial T2-weighted (b), and sagittal T2-weighted (c) images of the reconstructed breast show enlarged level I and II axillary lymph nodes (arrows). Biopsy of the axillary nodes revealed moderately differentiated infiltrating ductal carcinoma. m in a = pectoralis muscle.

View larger version (185K): [in this window] [in a new window] [Download PPT slide]   Figure 9c.  Nodal recurrence in a 50-year-old woman with an axillary mass after TRAM flap reconstruction. Axial T1-weighted (a), axial T2-weighted (b), and sagittal T2-weighted (c) images of the reconstructed breast show enlarged level I and II axillary lymph nodes (arrows). Biopsy of the axillary nodes revealed moderately differentiated infiltrating ductal carcinoma. m in a = pectoralis muscle.

Figure 10 demonstrates the MR imaging findings in a woman with a newly palpable abnormality 10 years following mastectomy and reconstruction. The MR images demonstrate a rapidly enhancing nodule in the inferior aspect of the TRAM flap reconstruction. Histologic analysis demonstrated a 1.0-cm infiltrating intraductal cancer with intraductal tumor arising within residual mammary parenchyma. As the original surgery took place in a different institution, attempts to obtain the prior pathologic specimen for differentiation between de novo malignancy versus tumor recurrence were unsuccessful.

View larger version (88K): [in this window] [in a new window] [Download PPT slide]   Figure 10a.  Delayed recurrence in a 51-year-old woman with a chest wall mass 10 years after mastectomy and TRAM flap reconstruction. (a, b) Sagittal T1-weighted (a) and unenhanced 3D fat-saturated GRE T1-weighted (b) images of the reconstructed breast show a spiculated lesion in the inframammary crease. (c) Sagittal gadolinium-enhanced 3D fat-saturated GRE T1-weighted image shows avid enhancement of the lesion.

View larger version (116K): [in this window] [in a new window] [Download PPT slide]   Figure 10b.  Delayed recurrence in a 51-year-old woman with a chest wall mass 10 years after mastectomy and TRAM flap reconstruction. (a, b) Sagittal T1-weighted (a) and unenhanced 3D fat-saturated GRE T1-weighted (b) images of the reconstructed breast show a spiculated lesion in the inframammary crease. (c) Sagittal gadolinium-enhanced 3D fat-saturated GRE T1-weighted image shows avid enhancement of the lesion.

View larger version (103K): [in this window] [in a new window] [Download PPT slide]   Figure 10c.  Delayed recurrence in a 51-year-old woman with a chest wall mass 10 years after mastectomy and TRAM flap reconstruction. (a, b) Sagittal T1-weighted (a) and unenhanced 3D fat-saturated GRE T1-weighted (b) images of the reconstructed breast show a spiculated lesion in the inframammary crease. (c) Sagittal gadolinium-enhanced 3D fat-saturated GRE T1-weighted image shows avid enhancement of the lesion.

	Discussion

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We acknowledge that this study is limited by lack of long-term follow-up in a number of patients. In retrospective studies such as this, patient follow-up may be incomplete. However, the negative predictive value of breast MR imaging is in general high, including patients in whom normal anatomy has been distorted by prior surgery and radiation therapy.

Currently, surveillance of TRAM flap reconstructions occurs primarily by means of physical examination. Multiple reports exist in the literature of nonpalpable recurrences that have been detected radiologically. A recent article by Helvie et al (29) advocates the routine mammographic screening of TRAM flap reconstructions. The use of MR imaging of TRAM flaps in asymptomatic patients has not been studied, to our knowledge, and was not the intent of this retrospective evaluation. However, our review of cases suggests that MR imaging may allow differentiation of benign from malignant findings in patients following breast reconstruction with a TRAM flap.

Further studies may be helpful to define whether routine evaluation of such patients with MR imaging would provide both earlier detection of local recurrence and more confident diagnosis of benign abnormalities without the need for invasive biopsy procedures. Currently, we do not advocate the use of MR imaging as a screening modality in patients with TRAM flap reconstructions. Instead, we believe MR imaging may be used as an adjunctive imaging modality for evaluation of newly apparent clinical abnormalities following TRAM flap reconstruction. Proposed uses of MR imaging include (a) confirming a benign imaging impression as demonstrated at mammography and US, (b) reinforcing radiologic suspicion of tumor recurrence as based on conventional imaging modalities, or (c) documenting the full extent of disease in cases of biopsy-proved recurrence.

	Acknowledgments

 
We thank David Low, MD, for the illustrations in Figures 1 and 2.

	Footnotes

 
Abbreviations: GRE = gradient-echo, 3D = three-dimensional, TRAM = transverse rectus abdominis myocutaneous

	References

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1. Hartrampf CR, Scheflan M, Black PW. Breast reconstruction with a transverse abdominal island flap. Plast Reconstr Surg 1982; 69:216-225.[Medline]
2. Elliott LF, Hartrampf CR. Breast reconstruction with rectus abdominis flaps. In: Noone RB, eds. Plastic and reconstructive surgery of the breast. Philadelphia, Pa: Decker, 1991; 420-436.
3. Hogge JP, Zuurbier RA, de Paredes ES. Mammography of autologous myocutaneous flaps. RadioGraphics 1999; 19:S63-S72.
4. LePage MA, Kazerooni EA, Helvie MA, Wilkins EG. Breast reconstruction with TRAM flaps: normal and abnormal appearance at CT. RadioGraphics 1999; 19:1593-1603.[Abstract/Free Full Text]
5. Shestak KC. Breast reconstruction with a pedicled TRAM flap. Clin Plast Surg 1998; 25:167-182.[Medline]
6. Schusterman MA. The free TRAM flap. Clin Plast Surg 1998; 25:191-195.[Medline]
7. Chang DW, Reece GP, Wang B, et al. Effects of smoking on complications in patients undergoing free TRAM flap breast reconstruction. Plast Reconstr Surg 2000; 105:2374-2380.[Medline]
8. Tran NV, Chang DW, Gupta A, Kroll SS, Robb GL. Comparison of immediate and delayed free TRAM flap breast reconstruction in patients receiving postmastectomy radiation therapy. Plast Reconstr Surg 2001; 108:78-82.[CrossRef][Medline]
9. Morris EA. Breast cancer imaging with MRI. Radiol Clin North Am 2002; 40:443-466.[CrossRef][Medline]
10. Orel SG, Schnall MD, Powell CM, et al. Staging of suspected breast cancer: effect of MR imaging and MR-guided biopsy. Radiology 1995; 196:115-122.[Abstract/Free Full Text]
11. Gilles R, Guinebretiere JM, Shapeero LG, et al. Assessment of breast cancer recurrence with contrast-enhanced subtraction MR imaging: preliminary results in 26 patients. Radiology 1993; 188:473-478.[Abstract/Free Full Text]
12. Heywang-Kobrunner SH, Schlegel A, Beck R, et al. Contrast-enhanced MRI of the breast after limited surgery and radiation therapy. J Comput Assist Tomogr 1993; 17:891-900.[Medline]
13. Orel SG, Schnall MD. MR imaging of the breast for detection, diagnosis, and staging of breast cancer. Radiology 2001; 220:13-30.[Abstract/Free Full Text]
14. Muuller RD, Barkhausen J, Sauerwein W, Langer R. Assessment of local recurrence after breast-conserving therapy with MRI. J Comput Assist Tomogr 1998; 22:408-412.[CrossRef][Medline]
15. Kinkel K, Hylton NM. Challenges to interpretation of breast MRI. J Magn Reson Imaging 2001; 13:821-829.[CrossRef][Medline]
16. Rieber A, Tomczak RJ, Mergo PJ, Wenzel V, Zeitler H, Brambs HJ. MRI of the breast in the differential diagnosis of mastitis versus inflammatory carcinoma and follow-up. J Comput Assist Tomogr 1997; 21:128-132.[CrossRef][Medline]
17. Lewis-Jones HG, Whitehouse GH, Leinster SJ. The role of magnetic resonance imaging in the assessment of local recurrent breast carcinoma. Clin Radiol 1991; 43:197-204.[CrossRef][Medline]
18. Dao TH, Rahmouni A, Campana F, Laurent M, Asselain B, Fourquet A. Tumor recurrence versus fibrosis in the irradiated breast: differentiation with dynamic gadolinium-enhanced MR imaging. Radiology 1993; 187:751-755.[Abstract/Free Full Text]
19. Harms SE, Flamig DP. Breast MRI. Clin Imaging 2001; 25:227-246.[CrossRef][Medline]
20. Coady AM, Mussurakis S, Owen AW, Turnbull LW. Case report: MR imaging of fat necrosis of the breast associated with lipid cyst formation following conservative treatment for breast carcinoma. Clin Radiol 1996; 51:815-817.[CrossRef][Medline]
21. Kinoshita T, Yashiro N, Yoshigi J, Ihara N, Narita M. Fat necrosis of the breast: a potential pitfall in breast MRI. Clin Imaging 2002; 26:250-253.[CrossRef][Medline]
22. Solomon B, Orel SG, Reynolds C, Schnall MD. Delayed development of enhancement in fat necrosis after breast conservation therapy: a potential pitfall for MR imaging of the breast. AJR Am J Roentgenol 1998; 170:966-968.[Free Full Text]
23. Fajardo LL, Roberts CC, Hunt KR. Mammographic surveillance of breast cancer patients: should the mastectomy site be imaged? AJR Am J Roentgenol 1993; 161:953-955.[Abstract/Free Full Text]
24. Noone RB, Frazier TG, Noone GC, Blanchet NP, Murphy JB, Rose D. Recurrence of breast carcinoma following immediate reconstruction: a 13 year review. Plast Reconstr Surg 1994; 93:96-106.[Medline]
25. Slavin SA, Love SM, Goldwyn RM. Recurrent breast cancer following immediate reconstruction with myocutaneous flaps. Plast Reconstr Surg 1994; 93:1191-1204.[Medline]
26. Helvie MA, Wilson TE, Roubidoux MA, Wilkins EG, Chang AE. Mammographic appearance of recurrent breast carcinoma in six patients with TRAM flap breast reconstruction. Radiology 1998; 209:711-715.[Abstract/Free Full Text]
27. Mies C. Recurrent secretory carcinoma in residual mammary tissue after mastectomy. Am J Surg Pathol 1993; 17:715-721.[CrossRef][Medline]
28. Aberizk WJ, Silver B, Henderson IC, Cady B, Harris JR. The use of radiotherapy for treatment of isolated locoregional recurrence of breast carcinoma after mastectomy. Cancer 1986; 58:1214-1218.[CrossRef][Medline]
29. Helvie MA, Bailey JE, Roubidoux MA, et al. Mammographic screening of TRAM flap breast reconstruction for detection of nonpalpable recurrent cancer. Radiology 2002; 224:211-216.[Abstract/Free Full Text]

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