Sex cord-stromal tumors of the pediatric testis present diagnostic and therapeutic challenges. This study examines the clinicopathologic features of 16 testicular sex cord-stromal tumors from children less than 18 years of age. Four juvenile granulosa cell tumors and five tumors of Sertoli or incomplete differentiation in this study had high mitotic rates and/or sarcomatoid areas that suggested malignancy, but none of these children developed recurrence or metastases. Some of these tumors had been initially misdiagnosed as yolk sac tumors or rhabdomyosarcomas because of the presence of areas superficially resembling these neoplasms. These morphologic pitfalls have received little attention in the literature. Even incompletely differentiated sex cord-stromal tumors have at least focal areas characteristic of juvenile granulosa or Sertoli cell differentiation. In addition, immunohistochemical negativity for alpha-fetoprotein, muscle specific actin, and desmin are useful for ruling out yolk sac tumor and rhabdomyosarcoma. Four patients had Leydig cell tumors and three had large cell calcifying Sertoli cell tumors. Children with Leydig cell tumors are not at risk for metastasis, but children with large cell calcifying Sertoli cell tumors are at risk for endocrine syndromes as illustrated by one of our cases. The differential diagnosis of these tumors is also discussed.

CLEAR-CELL CHONDROSARCOMA