Non-Germ Cell Tumors of the Testis

Approximately 5-6% of all testis tumors are non-germ cell tumors of the testis. Three types will be considered, namely, Leydig cell tumors, Sertoli cell tumors, and gonadoblastomas.

1. Leydig Cell Tumors

Epidemiology & Pathology

Leydig cell tumors are the most common non-germ cell tumors of the testis and account for 1-3% of all testicular tumors. They follow a bimodal age distribution: the 5- to 9-year-old and the 25- to 35-year-old age groups. Twenty-five percent of these tumors occur in childhood. Bilaterality is seen in 5-10% of cases. The cause of these tumors is unknown; unlike germ cell tumors, there is no association with cryptorchidism.

Pathologic examination reveals a small, yellow, well-circumscribed lesion devoid of hemorrhage or necrosis. Microscopically, hexagonally shaped cells with granular, eosinophilic cytoplasm containing lipid vacuoles are seen. Reinke crystals are fusiform-shaped cytoplasmic inclusions that are pathognomonic for Leydig cells.

Clinical Findings

Prepubertal children usually present with virilization, and tumors are benign. Adults are usually asymptomatic, although gynecomastia may be present in 20-25%. Ten percent of tumors in adults are malignant. Laboratory findings include elevated serum and urinary 17-ketosteroids as well as estrogens.

Treatment & Prognosis

Radical orchiectomy is the initial treatment for Leydig cell tumors. Clinical staging is similar to that for germ cell tumors, and levels of the 17-ketosteroids can be helpful in distinguishing between benign and malignant lesions. Elevations of 10-30 times normal are typical of malignancy. RPLND is recommended for malignant lesions. Because of the rarity of these lesions, the role of chemotherapy remains to be defined. Prognosis is excellent for benign lesions, while it remains poor for patients with disseminated disease.

2. Sertoli Cell Tumors

• Tumors of the Testis
  
  
  
  • Germ Cell Tumors of the Testis
    
  • Non-Germ Cell Tumors of the Testis