Spontaneous renocolic fistula: a rare occurrence associated with renal cell carcinoma.

A patient with abdominal discomfort, weight loss, and general weakness was discovered by way of ultrasound and computed tomography to have a tumor in the lower pole of the left kidney. At a second computed tomography examination, the mass had shrunken and air-fluid levels and contrast medium from previous examinations were evident, confirming a renocolic fistula. The patient underwent en bloc left radical nephrectomy with resection of the descending colon. Renal cell carcinoma was confirmed histologically. The patient has been free of disease for 4 years. Such fistulas are usually related to renal calculi or tuberculosis but, of late, more have been the result of iatrogenic trauma sustained during percutaneous renal procedures and lithotripsy. Use of computed tomography and other imaging methods should enable early detection of most renocolic fistulas, which usually are a late manifestation of advanced renal disease.