Secondary polycythemia as a paraneoplastic syndrome of testicular seminoma.

A 45-year-old man was referred to our hospital because of polycythemia. A physical examination revealed a large tumor in his scrotum enlarged to the size of 13 x 10 cm. A laboratory examination revealed severe erythrocytosis with a red blood cell count of 6,820 x 10(9)/L, a hemoglobin concentration of 21.2 g/dL, and a hematocrit of 59.8%. The total red cell volume was increased. A right radical orchidectomy was done with minimum bleeding, and he was diagnosed as having pure seminoma. After the operation, polycythemia improved spontaneously. Polycythemia is a rare complication of seminoma and only two cases have been reported previously. The precise mechanism of polycythemia in our patient could not be clearly evaluated, but clinical course did indicate a close relationship between two distinct disorders.