Testicular cysts: differentiation with US and clinical findings.

In 34 of 847 patients (4%), testicular cysts were discovered with high-resolution ultrasound (US). Sixteen had a cystic testicular tumor, and US images showed multiple cysts and solid tumor portions in 12 of these 16 (75%). Eighteen patients had nonneoplastic cysts: Five had cysts of the tunica albuginea, and 13 had intratesticular cysts. All tunica albuginea cysts were palpable as small masses, and only US images showed that the masses were cystic. None of the 13 intratesticular cysts was palpable; all were accidentally discovered with US, which showed that 12 were single cysts with a marginal location (92%). On histologic studies, the nonneoplastic cysts were related to the spermatic ducts (rete testis, efferent ductules) and frequently appeared as postinflammatory alterations. Only five patients with intratesticular cysts were followed up with US, and no changes occurred. The combination of clinical and US findings facilitated the differentiation between nonneoplastic and neoplastic testicular cysts.