Tumours of the genito-urinary tract in renal transplant recipients: clinical and radiographic findings

In order to study the clinical and radiological manifestations of post-transplantation malignant genito-urinary tumours in kidney recipients, we reviewed nine cases of genito-urinary neoplasms among 65 malignancies which developed in 61 of 620 kidney recipients. Ultrasound (US) and CT examinations were available in all the cases and MRI imaging in three. For each patient we reviewed the date of transplantation, immunosuppressive therapy, pathology and surgical reports and relevant radiographic studies. We determined tumour volume, the presence of necrosis and tumour extension. The malignant tumours included B-cell non-Hodgkin lymphomas of the native kidney (2) and urinary bladder (1), renal cell carcinoma (1), urotheliomas of the renal pelvis (1), ureter (1) and bladder (1), epidermoid carcinoma of the renal pelvis (1) and embryonal testicular carcinoma (1). Two of the three lymphomas developed in cyclosporine-treated recipients and regressed after reduction of the cyclosporine dose. The lymphomas presented as solid masses with necrosis visible on T2-weigthed MRI images. Other non-lymphomatous neoplasms were characterised by a large tumour volume and advanced local and regional extension. Five patients died within 2 years after diagnosis. It is concluded that the high incidence of malignancies (9.8 %), especially of the genito-urinary tract (1.4 %), and their advanced stage warrant radiographic follow-up studies.