[Synchronous neoplasms of the colon and kidney: analysis of 2 case reports]

Up until only a few decades ago synchronous renal cell carcinoma associated with primary tumors of other organs was diagnosed almost exclusively in necropsy series. Recently the widespread use of ultrasonography and CT has permitted diagnosis of clinically silent renal cell carcinoma in patients undergoing a work-up for other primary tumors. We report two cases of synchronous colon and renal cancer: 1) a 75 year old woman presented bilateral pulmonary nodules at chest X-Ray and stratigraphy. Total-body CT scan showed multiple, apparently metastatic, bilateral pulmonary lesions and two tumors in the right kidney and ascending colon. A right nephrectomy and right hemicolectomy were performed. She succumbed after 18 months as a result of metastatic spread to the liver, lungs and bone; 2) a 64 year old man was discovered to have a colon cancer during a barium enema examination and endoscopy. CT scan of the abdomen yielded an incidental diagnosis of a tumor in the left kidney. A left nephrectomy and left hemicolectomy were performed. After 6 months CT revealed no evidence of recurrence or metastases. Histology findings revealed two primary malignancies in both cases: a clear cell renal carcinoma and an adenocarcinoma of the colon.