Colonic melanosis is not precancerous.
Colonic acanthosis nigricans is a kind of non-inflammatory intestinal disease with black pigmentation of colonic mucosa, which occurs in people with long-term constipation and difficulty in defecation, and is mostly caused by patients taking anthraquinone laxatives, such as rhubarb, heshouwu, bitter ginseng, tiger nut, cassia seed, senna, aloe vera, etc. For the treatment, patients should stop taking this kind of laxative, and eat more food rich in dietary fiber.
Pre-cancerous lesions of the colon include ulcerative colitis, adenomatous colon polyps and other diseases. Ulcerative colitis is a chronic inflammatory bowel disease, and patients with a long and prolonged course of the disease may develop cancer. Adenomatous colon polyps, although cancerous, are benign for the time being and can be prevented by early endoscopic surgical removal.
Pre-cancerous colon lesions can be prevented by regular colonoscopy.