Diagnosis and Management of a De Novo Urothelial Carcinoma in a Kidney Allograft: A Case Report

Abstract

IntroductionFollowing renal transplantation, the incidence of malignancies is 3–5 times higher than that of healthy individuals. Among other type of cancers, the risk of urological tumors is also elevated. However, only a few cases of de novo transitional cell carcinomas occurring in renal allografts have been reported. Case reportA 63-year-old tertiary transplanted male patient was urgently hospitalized for a painless macroscopic hematuria. Ultrasonography revealed pyelectasis and a hematoma in the renal pelvis. A percutaneous nephrostomy tube was inserted. An anterograde pyelography was performed later, where a filling defect was still observable in the location of the previously reported hypoechoic mass. Contrast-enhanced ultrasonography showed enhancement of the lesion. An ultrasound-guided percutaneous biopsy was performed. The histologic evaluation revealed a high-grade transitional cell carcinoma. A whole-body staging computed tomography scan did not show signs of metastatic disease. The renal allograft was surgically removed. No disease progression was observed during the 21-month follow-up period. ConclusionsPainless hematuria and asymptomatic hydronephrosis occurring after kidney transplantation should raise the possibility of urothelial carcinoma in the kidney graft. Contrast-enhanced ultrasound should be considered as a first-line diagnostic modality because it is easily accessible and does not raise concerns about nephrotoxicity or radiation burden.