RESUMEN
Synchronous primary colon and renal cancer is a rare but real clinical entity reported with variable incidence. An 81-year-old man admitted for abdominal pain and melena is diagnosed with right colic tumor by colonoscopy and with simultaneous right kidney tumor by CT-scan. The patient is adequately prepared and scheduled for laparotomy. Both tumors are resected in the same surgical session with curative intent - right hemicolectomy and right radical nephrectomy. The patient recovered well and was discharged after 10 postoperative days. The microscopic examination indicated an adenocarcinoma in the sigmoid and a clear cell renal carcinoma in the kidney. Immunohistochemical staining did not find any compatibility between those tumors. The patient started chemotherapy and is under appropriate oncologic follow-up. Modern investigations allow detection of simultaneous malignancies making possible the planned simultaneous resection of both. Histopathologic examination will proof the diagnosis of primary different malignancies.