Primary tumors of the epididymis are rare and are most commonly benign. Adenomatoid tumors of the epididymis are the most common and typically occur in the third and fourth decade of life. They are typically asymptomatic, solid lesions that arise from any portion of the epididymis.

Leiomyomas are the second most common tumor of the epididymis. These lesions tend to be painful and are often associated with a hydrocele.

Cystadenomas are benign lesions of the epididymis that are bilateral in 30% of cases and are frequently seen in association with von Hippel-Lindau disease. Histologically these lesions are difficult to distinguish from renal cell carcinoma. Malignant lesions of the epididymis are extremely rare. In general, an inguinal approach should be used, and if frozen section confirms a benign lesion, epididymectomy should be performed. If a malignant tumor is diagnosed, radical orchiectomy must be performed.

Tumors of the spermatic cord are typically benign. Lipomas of the cord account for most of these lesions. Of the malignant lesions, rhabdomyosarcoma is the most common, followed by leiomyosarcoma, fibrosarcoma, and liposarcoma.

Clinical diagnosis of tumors of the spermatic cord can be difficult. Differentiating between a hernia and a spermatic cord tumor may be possible only at exploration. In general, these lesions should be approached through an inguinal incision. The cord should be occluded at the internal ring and frozen sections obtained. If malignancy is diagnosed, attention should be directed toward performing wide local excision to avoid local recurrence. Staging of disease is similar to that of testicular tumors. For rhabdomyosarcoma, RPLND should be performed with adjuvant radiotherapy and chemotherapy. The value of RPLND for the other malignant spermatic cord tumors remains to be determined. Prognosis relates to the histologic status, stage, and site of disease.