DOI: 10.1148/rg.253045188
RadioGraphics 2005;25:835-839
© RSNA, 2005
Best Cases from the AFIP
Bilateral Testicular Tumors: Seminoma and Mixed Germ Cell Tumor1
Walid K. Adham, MD,
Bharat K. Raval, MD,
Maria C. Uzquiano, MD and
Luciano B. Lemos, MD
1 From the Departments of Diagnostic Radiology (W.K.A., B.K.R.) and Pathology (M.C.U., L.B.L.), University of Texas Health Science Center at Houston, Lyndon B. Johnson General Hospital, 6431 Fannin St, Suite 2.026, Houston, TX 77030. Received October 6, 2004; revision requested November 4 and received December 17; accepted December 17. All authors have no financial relationships to disclose.
Address correspondence to W.K.A. (e-mail: walid.k.adham{at}uth.tmc.edu).
 |
History
|
|---|
A 36-year-old Caucasian man presented to the emergency department with a 14-month history of generalized scrotal discomfort and an increase in the size of both testes during the past 5 months. The patient also complained of a 2-month history of flank pain, low-grade fevers, and night sweats. At physical examination, the presence of bilateral, focal, firm, and nontender masses in both testes was confirmed. Laboratory studies revealed an 
-fetoprotein level of 18 mg/mL and a ß–human chorionic gonadotropin (ß-hCG) level of 30,000 mIU/mL.
|
Imaging Findings
|
|---|
Ultrasonography (US) of the scrotum demonstrated bilateral microlithiasis, a right scrotal hydrocele, and bilateral testicular masses (Figs 1 , 2).
View larger version (149K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 1a. Seminoma. (a) Longitudinal US image of the right testis demonstrates a hydrocele (arrow), diffuse microlithiasis (arrowheads), and a homogeneous mass with no definite normal testicular parenchyma. (b) Doppler US image shows a generalized increase in testicular vascular flow (2).
|
|
View larger version (94K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 1b. Seminoma. (a) Longitudinal US image of the right testis demonstrates a hydrocele (arrow), diffuse microlithiasis (arrowheads), and a homogeneous mass with no definite normal testicular parenchyma. (b) Doppler US image shows a generalized increase in testicular vascular flow (2).
|
|
View larger version (153K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2a. Mixed germ cell tumor. (a) Longitudinal US image of the left testis shows a heterogeneous, predominantly hypoechoic mass, with scattered areas of hypoechogenicity (arrowheads). Normal testicular parenchyma is compressed peripherally by the tumor and contains diffuse microlithiasis (arrow). (b) Doppler US image shows normal peripheral vascularity with absence of central flow.
|
|
View larger version (89K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2b. Mixed germ cell tumor. (a) Longitudinal US image of the left testis shows a heterogeneous, predominantly hypoechoic mass, with scattered areas of hypoechogenicity (arrowheads). Normal testicular parenchyma is compressed peripherally by the tumor and contains diffuse microlithiasis (arrow). (b) Doppler US image shows normal peripheral vascularity with absence of central flow.
|
|
Images of the right testis demonstrated enlargement, diffuse microlithiasis, and a homogeneous, hypervascular mass that replaced the majority of the testicular parenchyma (Fig 1). The right testis measured 7.5 x 4.3 x 3.5 cm.
Images of the left testis showed nearly complete replacement of the testis by a markedly heterogeneous mass with multiple areas of avascular hypoechogenicity, findings that suggest hemorrhage and necrosis (Fig 2). Microlithiasis was present at the site of residual normal testicular tissue at the margin of the tumor. The left testis measured 4.2 x 3.5 x 3.1 cm.
|
Pathologic Evaluation
|
|---|
The patient underwent bilateral radical orchiectomy. The specimens were fixed in buffered 10% formalin, and paraffin-embedded sections were stained with hematoxylin-eosin (H-E) stain.
The parenchyma of the right testis was largely replaced by a fleshy, multilobulated tumor that measured 7.0 x 4.6 x 3.0 cm. The cut surface of the tumor had a tan-white, homogeneous, multilobulated appearance (Fig 3). No areas of hemorrhage or necrosis were identified. The tumor was confined by the tunica albuginea. The epididymis was grossly compressed but free of tumor. The spermatic cord was grossly uninvolved by tumor.
View larger version (100K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 3. Photograph of both excised testes shows a homogeneous, multilobulated right testis (R), which is markedly enlarged compared with the left one. The left testis (L) is heterogeneous with extensive hemorrhage and retains normal testicular parenchyma.
|
|
The left testis contained a parenchymal tumor that measured 3.6 x 3.2 x 2.5 cm. It had a multilobulated appearance with extensive hemorrhage (Fig 3). The tumor was limited inside the tunica albuginea and did not involve the tunica vaginalis, epididymis, or spermatic cord.
Small areas of peripheral right testicular parenchyma revealed extensively atrophic tubules and hyperplasia of Leydig cells. The tumor was composed of clear cells with sharp borders and central hyperchromatic nuclei with one to two nucleoli arranged in sheets (Fig 4). The cells were surrounded by fibrous bands and inflammatory cells, which were predominantly lymphocytes. The tumor had large areas of necrosis. These pathologic findings are consistent with those of a classic seminoma.
View larger version (196K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4. Seminoma of the right testis. High-power photomicrograph (original magnification, x20; H-E stain) reveals clear cells with sharp borders and central hyperchromatic nuclei that contain nucleoli arranged in sheets (arrows).
|
|
The left testicular tumor was a mixed germ cell tumor with components of embryonal carcinoma (60%), choriocarcinoma (35%), mature teratoma (5%), and yolk sac tumor (<1%) (Fig 5).
View larger version (178K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5a. Mixed germ cell tumor of the left testis. (a) Low-power photomicrograph (original magnification, x4; H-E stain) of the mature teratoma component shows mature intestinal-type epithelium with goblet cells (white arrow) and squamous keratinized epithelium (black arrow). (b) High-power photomicrograph (original magnification, x20; H-E stain) of the embryonal cell component shows undifferentiated pleomorphic cells arranged in sheets. (c) High-power photomicrograph (original magnification, x20; H-E stain) of the choriocarcinoma component shows an admixture of syncytiotrophoblasts (black arrow) and cytotrophoblasts (white arrow) with extensive hemorrhage. (d) High-power photomicrograph (original magnification, x20; H-E stain) of the small focus of yolk sac tumor shows perivascular Schiller-Duval bodies (arrows).
|
|
View larger version (192K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5b. Mixed germ cell tumor of the left testis. (a) Low-power photomicrograph (original magnification, x4; H-E stain) of the mature teratoma component shows mature intestinal-type epithelium with goblet cells (white arrow) and squamous keratinized epithelium (black arrow). (b) High-power photomicrograph (original magnification, x20; H-E stain) of the embryonal cell component shows undifferentiated pleomorphic cells arranged in sheets. (c) High-power photomicrograph (original magnification, x20; H-E stain) of the choriocarcinoma component shows an admixture of syncytiotrophoblasts (black arrow) and cytotrophoblasts (white arrow) with extensive hemorrhage. (d) High-power photomicrograph (original magnification, x20; H-E stain) of the small focus of yolk sac tumor shows perivascular Schiller-Duval bodies (arrows).
|
|
View larger version (174K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5c. Mixed germ cell tumor of the left testis. (a) Low-power photomicrograph (original magnification, x4; H-E stain) of the mature teratoma component shows mature intestinal-type epithelium with goblet cells (white arrow) and squamous keratinized epithelium (black arrow). (b) High-power photomicrograph (original magnification, x20; H-E stain) of the embryonal cell component shows undifferentiated pleomorphic cells arranged in sheets. (c) High-power photomicrograph (original magnification, x20; H-E stain) of the choriocarcinoma component shows an admixture of syncytiotrophoblasts (black arrow) and cytotrophoblasts (white arrow) with extensive hemorrhage. (d) High-power photomicrograph (original magnification, x20; H-E stain) of the small focus of yolk sac tumor shows perivascular Schiller-Duval bodies (arrows).
|
|
View larger version (177K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5d. Mixed germ cell tumor of the left testis. (a) Low-power photomicrograph (original magnification, x4; H-E stain) of the mature teratoma component shows mature intestinal-type epithelium with goblet cells (white arrow) and squamous keratinized epithelium (black arrow). (b) High-power photomicrograph (original magnification, x20; H-E stain) of the embryonal cell component shows undifferentiated pleomorphic cells arranged in sheets. (c) High-power photomicrograph (original magnification, x20; H-E stain) of the choriocarcinoma component shows an admixture of syncytiotrophoblasts (black arrow) and cytotrophoblasts (white arrow) with extensive hemorrhage. (d) High-power photomicrograph (original magnification, x20; H-E stain) of the small focus of yolk sac tumor shows perivascular Schiller-Duval bodies (arrows).
|
|
|
Discussion
|
|---|
Synchronous and metachronous testicular tumors account for 1%–5% of all testicular cancer (1–3). Synchronous testicular tumors are much less common, as they account for approximately 10% of bilateral tumors. Most synchronous tumors have an identical histologic diagnosis (4). A recent literature review of 42 reported cases of synchronous bilateral testicular germ cell tumors with different histologic characteristics demonstrated that only six patients presented with concurrent seminomatous and mixed germ cell tumors (4).
Seminoma is a malignant germ cell tumor composed of relatively uniform cells (that resemble primitive germ cells) with a clear cytoplasm, well-defined borders, and nuclei with one or more prominent nucleoli (5). Seminoma is the most common pure germ cell tumor of the testis and accounts for 35%–50% of all germ cell tumors (5–8). Patients typically present with a self-detected testicular mass that is sometimes associated with an ill-defined aching sensation in the lower abdomen, inguinal region, or scrotum. The average age of men presenting with seminomas is 40.5 years (6). An estimated 5%–25% of men with testicular seminomas have elevated levels of ß-hCG, which is produced by syncytiotrophoblastic giant cells (9). The elevated level of ß-hCG is typically not high enough, however, to cause clinical symptoms such as gynecomastia (8).
Imaging findings of seminomas reflect the uniform cellular configuration of these tumors. US typically demonstrates a rounded, well-circumscribed, hypoechoic, and homogeneous mass that does not contain significant cystic or calcific foci (7). The tumor is less aggressive than other testicular neoplasms and is therefore usually confined by the tunica albuginea (7).
Mixed germ cell tumors are malignant neoplasms that contain more than one germ cell tumor component, excluding seminoma with syncytiotrophoblastic cells (5). In a study of 1,053 cases by Jacobsen et al (10), mixed germ cell tumors constituted 69% of all nonseminomatous germ cell tumors and 32% of all testicular germ cell tumors. Embryonal carcinoma is the most common component and is often combined with teratoma, seminoma, or yolk sac tumor (6). Patients with these tumors typically present with testicular enlargement, which is sometimes associated with pain. The average age of men presenting with mixed germ cell tumors is 30 years, and these tumors rarely occur in prepubertal patients. Serum marker elevation is common and is reflective of the individual components of the tumor. Elevation of -fetoprotein occurs in 60% of patients, whereas ß-hCG levels are elevated in approximately 55% (5). The components of the tumor are associated with areas of necrosis, hemorrhage, and cystic degeneration (5).
Imaging findings of mixed germ cell tumors are reflective of their different histologic components. US typically demonstrates a unilateral, mixed solid and cystic mass. The heterogeneous sonographic appearance is caused by hemorrhage, necrosis, histopathologic heterogeneity, or a combination thereof. Calcifications occur in 40% of cases (9).
The role of magnetic resonance (MR) imaging for evaluating testicular tumors continues to be investigated. MR imaging has been proposed as a useful diagnostic tool for cases in which the results of physical examination and US are inconclusive (11). Although US is highly sensitive in the detection of testicular masses, it is nonspecific for the diagnosis of tumor. Detection of a tumor is difficult when the entire testicular parenchyma is replaced by neoplasm, especially when the contralateral testis has been removed (12). US does not have sufficient resolution for reliable visualization of the testicular septations and tunica albuginea. MR imaging provides higher resolution and sensitivity for differentiation of testicular tissue, capabilities that facilitate improved depiction of small tumors that may not be detectable with US (12). MR imaging is also useful for differentiating histologic types of testicular tumors (12). Seminoma typically has a nodular appearance and a homogeneous low signal intensity on T2-weighted images. Mixed germ cell tumors, in contrast, are inhomogeneous in signal intensity, depending on the histologic components and presence of hemorrhage. MR imaging is therefore considered a useful adjunct for evaluating testicular tumors for which the clinical and US findings are discrepant, as well as for further characterization of the tumoral extent (13).
Several recent studies have reported that the prevalence of bilateral testicular cancer is increasing. Theories attempting to explain this increased prevalence mention the overall improvement in survival as well as earlier manifestation of testicular cancer in patients (2). In a study of 58 patients who presented with bilateral testicular tumors at Memorial Sloan Kettering Cancer Center, the patients with bilateral testicular germ cell tumors had clinical outcomes similar to those of patients with unilateral testicular tumors when tumor stage was matched (2).
Because there are no lymphatic or vascular connections between the testes, it is thought that synchronous tumors develop independently as two separate primary tumors (4). Standard treatment for metachronous testicular germ cell tumors is based on the histologic features and stage of the primary tumor. For patients with synchronous tumors, treatment is typically based on tumor stage and the nonseminomatous elements present in either testis, since they are considered more malignant (2,4). Bilateral orchiectomy is still considered the standard of care for local treatment and definitive pathologic diagnosis (4). Because bilateral orchiectomy is associated with severe endocrinologic and psychologic distress, chemotherapy and testis-preserving surgery are being considered for patients with early stages of cancer (4). A large series of 73 patients with bilateral testicular germ cell tumors treated with testis-preserving surgery and radiation therapy showed that 99% of the patients had no evidence of disease after a median follow-up of 7 years (14). These patients had tumors that were smaller than 15 mm.
The patient in our case was found at staging evaluation with computed tomography to have metastases to the retroperitoneal lymph nodes and tumor thrombosis of the left renal vein. He was treated with bilateral radical orchiectomy followed by chemotherapy. At the current time, which is approximately 1 year after the initial diagnosis, the patient is tumor free.
|
References
|
|---|
- Tabernero J, Paz-Ares L, Salazar R, et al. Incidence of contralateral germ cell testicular tumors in South Europe: report of the experience at 2 Spanish university hospitals and review of the literature. J Urol
2004; 171:164–167.[CrossRef][Medline]
- Holzbeierlein JM, Sogani PC, Sheinfeld J. Histology and clinical outcomes in patients with bilateral testicular germ cell tumors: the Memorial Sloan Kettering Cancer Center experience 1950 to 2001. J Urol
2003; 169:2122–2125.[CrossRef][Medline]
- Pamenter B, De Bono JS, Brown IL, et al. Bilateral testicular cancer: a preventable problem? Experience from a large cancer centre. BJU Int
2003; 92:43–46.[CrossRef][Medline]
- Coli A, Bigotti G, Dell’Isola C, et al. Synchronous bilateral testicular germ cell tumor with different histology. Urol Int
2003; 71:412–417.[CrossRef][Medline]
- Ulbright TM, Amin MB, Young RH. Atlas of tumor pathology: tumors of the testis, adnexa, spermatic cord, and scrotum. 3rd ser, fasc 25. Washington, DC: Armed Forces Institute of Pathology, 1997; 59–191.
- Woodward PJ, Sohaey R, O’Donoghue MJ, Green DE. Tumors and tumorlike lesions of the testis: radiologic-pathologic correlation. RadioGraphics
2002; 22:189–216.[Abstract/Free Full Text]
- Howlett DC, Marchbank ND, Sallomi DF. Ultrasound of the testis. Clin Radiol
2000; 55:595–601.[CrossRef][Medline]
- Classen J, Souchon R, Hehr T, Bamberg M. Treatment of early stage testicular seminoma. J Cancer Res Clin Oncol
2001; 127:475–481.[CrossRef][Medline]
- Ueno T, Tanaka YO, Nagata M, et al. Spectrum of germ cell tumors: from head to toe. RadioGraphics
2004; 24:387–404.[Abstract/Free Full Text]
- Krag Jacobsen G, Barlebo H, Olsen J, et al. Testicular germ cell tumours in Denmark 1976–1980: pathology of 1058 consecutive cases. Acta Radiol Oncol
1984; 23:239–247.[Medline]
- Muller-Leisse C, Bohndorf K, Stargardt A, et al. Gadolinium-enhanced T1-weighted versus T2-weighted imaging of scrotal disorders: is there an indication for MR imaging? J Magn Reson Imaging
1994; 4:389–395.[Medline]
- Cramer BM, Schlegel EA, Thueroff JW. MR imaging in the differential diagnosis of scrotal and testicular disease. RadioGraphics
1991; 11:9–21.[Abstract]
- Thurnher S, Hricak H, Carroll PR, Pobiel RS, Filly RA. Imaging the testis: comparison between MR imaging and US. Radiology
1988; 167:631–636.[Abstract/Free Full Text]
- Heidenreich A, Weibach L, Holtl W, et al. Organ sparing surgery for malignant germ cell tumour of the testis. J Urol
2001; 166:2161–2165.[CrossRef][Medline]
Top
History
Imaging Findings
