[Clinicopathologic features of testicular seminoma with syncytiotrophoblastic cells: Analysis of 3 cases and review of the literature].

Objective To investigate the clinical and histopathologic features of testicular seminoma with syncytoplasmic trophoblastic components. METHODS Using light microscopic staining, we analyzed the clinical and histopathologic characteristics, diagnosis, differential diagnosis and prognosis of 3 cases of testicular seminoma with syncytoplasmic trophoblastic components, and reviewed the relevant literature. RESULTS All the 3 cases were typical seminoma with syncytiotrophoblastic giant cells. Immunohistochemistry showed strong expressions of CD117 OCT-4, SALL4 and PLAP in diffuse tumor cells, and that of hCG in syncytiotrophoblastic cells. Continuous monitoring and consultation exhibited normal levels of serum β-hCG in all the cases after postoperative chemotherapy. CONCLUSIONS Testicular seminoma with syncytiotrophoblastic giant cells and increased serum β-hCG is a rare subtype, which occurs mostly in young people, sensitive to chemotherapy postoperatively and with a relatively good prognosis.