Upper tract transitional cell carcinoma clinically mimicking inflammatory renal pathology: A report of three cases.

Upper tract urothelial carcinoma (UTUC) of the renal pelvis and the ureter is incidentally detected in a small proportion of cases. However, the majority of UTUC cases present with hematuria, flank pain, and clot colic. Typical imaging features include hydronephrosis of the kidney (s) due to obstruction by the mass with a soft-tissue lesion that typically shows low-grade enhancement with or without a filling defect. Rarely, such a tumor may present with signs and symptoms mimicking an inflammatory or infective pathology of the kidney and is diagnosed only on biopsy or on nephrectomy. We present three such patients and cite another similar case we have published earlier. All three of these patients presented with signs and symptoms of an obstructed infected kidney with long-standing renal calculi and a forgotten DJ stent in one instance. Nephrectomy for the presumed infected kidney in all three cases revealed high-grade UTUC. In patients presenting with equivocal findings on cross-sectional imaging with a history of renal calculi or foreign bodies, we should have a high index of suspicion for malignancy.