Chromophobe Renal Cell Carcinoma of a Renal Allograft.

BACKGROUND Kidney transplantation is a treatment option for patients with end-stage renal disease. However, life-long immunosuppressive therapy, which is obligatory for renal transplant recipients, increases the risk of cancer recurrence and de novo tumor formation. Cancer is one of the leading causes of death in kidney transplant recipients. Renal cell carcinoma (RCC) of an allograft kidney is an extremely rare type of neoplasm and occurs in only about 0.22-0.25% of all kidney recipients. RCC is often asymptomatic and can be an incidental finding on routine examination. CASE REPORT In this case study, we describe a patient who developed chromophobe renal cell carcinoma 3 years after kidney transplantation from a living related donor. At the time of detection of the tumor, the graft function was impaired. A renal allograft biopsy was performed, and the pathological examination showed signs of chronic inflammation and chronic graft rejection. The graft biopsy failed to differentiate between oncocytoma and chromophobe carcinoma. Due to impaired graft function, presence of neoplasm in the graft, and morphologic chronic rejection, it was decided to perform a transplantectomy. The final histological examination showed the eosinophilic type of chromophobe carcinoma. CONCLUSIONS Chromophobe carcinoma in a kidney allograft is extremely rare in kidney transplant recipients. This clinical observation confirms the necessity and effectiveness of regular ultrasound and magnetic resonance imaging of the graft, not only for monitoring the functioning of the graft, but also for early detection of neoplasms in the transplanted kidney.