Extragonadal seminoma after renal transplantation and immunosuppression; treatment in the presence of renal dysfunction: a case report and literature review.

A 37-yr-old man who had undergone renal transplantation for end-stage renal failure presented with a large right pelvic mass obstructing the transplanted kidney. Initially, this was diagnosed as an anaplastic tumor while he had been on immunosuppressive treatment for kidney allograft rejection after transplantation. Despite difficulties of classic histopathology to reveal the origin of his tumor, FISH analysis revealed the presence of chromosome 12p abnormalities, strongly indicative of a germ-cell tumor-more likely seminoma-with extragonadal presentation. Because of renal dysfunction, he was treated with carboplatin (dose adjusted according to renal clearance) and etoposide, and when he experienced a rather atypical progression with bone metastases, he was treated with single-agent paclitaxel, and died almost 13 mo after initial presentation. The case adds further to the existing small list of seminoma/GCTs developing in transplant recipients, points to the unusual presentation patterns and diagnostic histopathology challenges, and presents the difficulty in therapeutic options, as a result of frequent renal dysfunction and intercurrent immunosuppressive therapy. All of these issues together with an extensive literature review are discussed in detail.