Colonic metastasis from primary carcinoma of the lung: report of a case and review of Japanese literature.

We report a rare case of colonic metastasis from primary carcinoma of the lung. A 59-year-old man who underwent pulmonary surgery for lung cancer was referred to our hospital in June 2007. The patient complained of abdominal pain, and barium enema examination at another hospital had demonstrated a descending colon tumor. Postoperative histopathological and immunohistochemical findings indicated that the tumor was a colonic metastasis of lung cancer. Three months postoperatively, the cancer had metastasized to the brain, and the patient underwent radiotherapy. He survived for more than 1 year after colonic surgery. Clinically apparent metastases from lung cancer to the colon are rare, and in the 50 Japanese cases retrospectively investigated here, the prognosis was poor.