Epidermoid Cyst of the Testis

Epidermoid cysts are uncommon testicular tumors accounting for approximately 1% of all testicular neoplasms. The primary differential diagnoses are dermoid cyst and mature teratoma of the testis. Dermoid cyst can be distinguished from epidermoid cyst by the presence of adnexal structures, while teratoma can be distinguished from epidermoid cyst by the presence of other components, commonly from all 3 germ layers, and by its association with intratubular germ cell neoplasia. The distinction from postpubertal mature testicular teratoma is of great importance as teratomas are malignant tumors that may have associated metastasis of either teratomatous or nonteratomatous germ cell tumor types. Treatment of epidermoid cyst of the testis is controversial. Some authors recommend orchiectomy, while others recommend testis-sparing surgery if certain diagnostic criteria are met, including the absence of intratubular germ cell neoplasia in samples of the surrounding parenchyma.