Testicular Seminoma Occurring After Kidney Transplantation in a Patient Previously Treated for Teratoma: De Novo Malignancy or Recurrence in a Different Histologic Form?

The most common testicular tumor is seminoma, but it is one of the rarest malignancies in kidney transplant recipients, with only 15 cases published in the English-language literature. Except in 1 case of recurrence, all cases were de novo malignancies after transplantation. We bring a case of a patient treated for testicle teratoma at age 24 years who received a kidney transplant at age 40 years, and 19 months after transplantation was diagnosed with a metastatic seminoma. To the best of our knowledge, there are no data of germ cell tumor late recurrence after kidney transplantation. In addition, this is the 1st case of a giant cell tumor occurring in a form of seminoma in general or transplanted population.