Chronic diarrhea due to metastatic breast cancer.

We report the case of a patient with chronic diarrhea due to infiltrative cancer to the colon from the breast. A 49-year-old woman with a history of metastatic breast cancer to the bones was admitted to hospital with 4 weeks of watery diarrhea. Computed tomography (CT) scan of the abdomen showed pancolitis. Colonoscopy showed patchy subepithelial hemorrhages, most prominently in the ascending colon and sigmoid colon, but no mass lesion. Random biopsies taken throughout the colon showed infiltrative adenocarcinoma of breast origin in multiple specimens. Infectious work-up was negative.