Spontaneous renoalimentary fistula as a complication of upper tract urothelial carcinoma: unknown complication of a rare disease.

Fistulae of the upper urinary tract with the alimentary tract are rare. Most cases of renoalimentary fistulae are secondary to penetrating trauma, which may be iatrogenic or due to locally invasive benign infective processes or complicated nephrolithiasis, or following surgical procedures. Spontaneous renoalimentary fistulae developing secondary to locally advanced malignancies, namely renal cell carcinoma, are very rare, and unknown due to upper tract transitional cell carcinoma. We present a case where a 60-year-old man, presented with clinical symptoms suggestive of upper gastrointestinal tract pathology, with no urological complaints and was diagnosed to have a renoalimentary fistula on cross-sectional imaging and upper gastrointestinal endoscopy with histopathology of duodenal growth biopsy showing high-grade transitional cell carcinoma. Due to unresectable nature of this mass, this patient had a gastric and biliary diversion and was started on palliative chemotherapy. Renoalimentary fistulae due to benign inflammatory causes may be treated by nephrectomy with or without resection of the involved bowel segment. However, all malignant fistulae have to be treated as locally advanced tumours and en bloc resection should be attempted whenever feasible.