Teaching Case

2 months history of abdominal distention and vague pain in the left iliac fossa. On clinical examination a medium sized, firm and non-tender mass was palpable in the left iliac fossa. The left testis could not be palpated Laboratory findings included an increased lactate dehydrogenase (LDH) level. Alphafetoprotein (AFP) and beta-chorionic gonadotropin (B-HCG) levels were normal.

The black patient, with a 2 months history of abdominal distention and vague pain in the left iliac fossa. On clinical examination a medium sized, firm and non-tender mass was palpable in the left fossa. The left testis could not be palpated Laboratory findings included an increased lactate dehydrogenase (LDH) level. Alphafetoprotein (AFP) and beta-chorionic gonadotropin (B-HCG) levels were normal. Pelvic ultrasonography and abdominal CT scan were performed. CT scans of head and thorax revealed no abnormalities. Scrotal ultrasonography confirmed the absence of the left testicle. Imaging findings were suggestive for cryptorchidism with neoplastic transformation of the testis. Spread to the contralateral seminal vesicle and to the left inferior phrenic lymph node (not shown) was suggested. Transrectal puncture biopsy of the right seminal vesicle revealed a seminoma. Surgery was performed and followed by chemio- and radiotherapy. Histological analysis of the resected specimen confirmed the diagnosis.

Testicular cancer is the most common malignancy in males aged 25 to 34 years. Cryptorchidism is a well known predisposing factor, increasing the risk for development of cancer 30 to 50 times. The risk is greater for abdominal than for inguinal locations of the testes. In addition, intra-abdominal testicular neoplasms can be complicated by torsion and may present with symptoms of acute abdomen. The incidence of testicular seminoma is low in blacks, although incomplete descent of the testes is more common in blacks and mixed-race than in white individuals. The major pathway of tumor spread is similar to that of seminoma developing in an orthotropic, scrotal testicle, i.e. lymphatic spread, most commonly to the lumbar lymph nodes. Contiguous spread to the adjacent organs may also occur. Seminomas tend to be moderately hypoechoic and relatively homogeneous on ultrasonography. Doppler ultrasonography is of limited value for the diagnosis, and may show a low resistive index (0.5 to 1.0). CT scan is useful to localize the abdominal testis, to assess neoplastic involvement and to screen for adenopathies. The CT appearance of seminomas is that of a hypodense, slightly enhancing mass containing low-density areas. Calcifications are rare. On MRI, just like scrotal testes, the undescended testis is hypointense relative to fat on T1- and iso- to hyper-intense on T2-weighted sequences. Neoplastic transformation is characterized by signal inhomogeneity and low signal intensity especially on long TR/TE images. Both CT scan and MRI are well suited for examination of the malignant transformation in undescended testis. MRI is superior in tissue characterization and allows multiplanar imaging. CT, in contrast, is better for detection of intratumoral calcifications and, due to more widely spread, is recommended for follow-up.