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A 61-year-old male asked:

Hi doctors. my stool appeared blackish, but when i wiped it was yellow. i had a colonoscopy last october 2020 which showed diverticulosis but no colon cancer. could colon cancer develop in that time?

1 doctor answer1 doctor weighed in
Dr. Philip Schwarzman
Emergency Medicine 46 years experience
Black stools are seen with upper GI bleeding (coming from the stomach) but would not clear so quickly. Certain foods and medicines can cause black stools (eg. iron, Pepto-Bismol). Colon cancer would not develop in 1 year.
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Last updated May 10, 2022


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