Following 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.A 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.Painless 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.
