Seminoma with syncytiotrophoblastic giant cells. A special form of seminoma.

Testicular seminomas may occur in various forms, of which the classical and spermatocytic are distinct, the anaplastic or atypical seminomas, however, less clearly defined. Lately, a separate group of particular clinical significance, comprising seminomas with syncytiotrophoblastic giant cells (STGC), has been specified. Although this type of seminoma had been recognized morphologically long ago, recent investigations have shown its ability to secret HCG, a fact that raises serious difficulties in its differential diagnosis with combined seminomas and choriocarcinomas. Two cases of seminomas with STGC are presented and pertinent clinical and morphologic problems discussed.