An Aggressive Urothelial Carcinoma in a Horseshoe Kidney-A Case Report

Evidence of horseshoe kidney in Indian population is 1 in 600-800 individuals. Horseshoe kidney is predisposed to complications by virtue of its ectopic position, malrotation and associated vascular and ureteral anomalies. Incidence of Renal Cell Carcinoma (RCC) in a horseshoe kidney is same as that in general population. Other pelvic tumours, transitional tumours, Wilms tumour and carcinoids show a greater frequency. High grade urothelial carcinomas are quite rare with a few case reports available. An index case of 75 yeal old male presented with renal mass in an incidentally diagnosed horseshoe kidney on radiologic imaging. The case has been highlighted due to its poorly differentiated tumour morphology and aggressive nature. Further, immunohistochemistry was done to arrive at a correct diagnosis for appropriate treatment. The tumour cells showed positivity for Cytokeratin 7 (CK 7) and CK 5/6. They were negative for p63, PAX-8 (Paired-box gene 8). Also, it is technically difficult to excise large-sized renal mass in an anomalous kidney.