Metastatic extragonadal seminoma associated with cardiac transplantation

A 37-year-old man who had successfully undergone cardiac transplantation for dilated cardiomyopathy presented with a history of severe pain over his left shoulder, rib cage and thoracic spine. Clinical examination revealed the presence of bony tenderness over these sites, but there was no other clinical evidence of malignancy. Further investigations suggested the presence of multiple bony metastases. Bone biopsy revealed extensive bone marrow infiltration by large undifferentiated cells showing pronounced cytoplasmic vacuolation with a striking granulomatous reaction. Immunocytochemistry revealed these anaplastic cells to be cytokeratin and placenta-like alkaline phosphatase positive but S100, CD30 and lymphoid marker negative. Analyses by in situ hybridisation of these cells revealed no evidence of Epstein-Barr virus infection. Overall the pathology suggested a diagnosis of metastatic seminoma. Confirmation of this diagnosis was obtained by the analysis of serum human chorionic gonadotrophin which was elevated at 90 IU/l. In the absence of testicular or retroperitoneal disease, it is very likely that this unusual case of metastatic seminoma was related to the patient's immunosuppressive therapy, which at diagnosis included cyclosporin and prednisolone. The patient was successfully treated with cisplatin based chemotherapy and decreased immunosuppression and remains in complete remission one year after completion of chemotherapy. Seminoma is an uncommon complication of prolonged immunosuppression with very few cases being described in the literature post-organ transplantation. This case shows that the clinical presentation of this treatable tumour in this patient population can be unusual and difficult to diagnose.