A large growth in the mucosa or lumen of the colon with an ulcerated surface of the mass and bleeding could be colon cancer, and inflammation of the colon or ulcerative colitis cannot be excluded. There is a mass in the colon with ulcerated surface bleeding. Firstly, it is necessary to exclude whether it is colon cancer. It is recommended that patients need to cooperate with pathologic biopsy under colonoscopy along with electronic colonoscopy. After excluding intestinal malignant tumor, it is possible to consider inflammatory bowel disease or larger intestinal polyps, which need to be actively anti-inflammatory and symptomatic treatment according to the relevant examination results, such as intravenous antibiotics to which the patient is not allergic, for example, levofloxacin or cefixime and other antibiotics, and radiofrequency resection of larger polyps can be carried out under the colonoscopy. If you find large colonic proliferation, surface ulceration, easy to bleed, you should actively seek medical treatment, specific examination and treatment should be carried out under the guidance of a professional doctor, to avoid delaying the aggravation of the condition.