Epidermoid cysts of the testis: a report of three cases and an analysis of 141 cases from the world literature.

Epidermoid cysts of the testis are rare and represent about 1% of all testicular tumors. An analysis of 141 cases reported to date in the world literature, including the cases reported here, indicates that 50% of the lesions occur in the third decade and 86% between the second and fourth decade. The most common presentations are painless enlargement of the testis (41%) for an average period of 2.25 years or incidental detection during routine physical examination (33%). Clinically, a discrete testicular nodule can be palpated in the majority of the cases (76%). Pathologic findings are those of a squamous lined cyst containing keratin with absence of appendages or other elements. It is believed that, despite the benign nature of the lesion, they should be treated by orchiectomy so that a thorough pathologic examination can be done to establish a confident diagnosis. While some controversy exists about their source of origin, all the evidence, including the age, more common occurrence among whites, and the rare reported cases arising in cryptorchid testis points to a germ cell origin for these lesions. The epidermoid cyst should thus be recognized as another subtype in the category of germ cell tumors of the testis and perhaps the ovary.