Colorectal adenomas are precancerous lesions and should be treated promptly once they are detected. Most adenomas can be resected by colonoscopy, while those that cannot be resected by colonoscopy (most of them are villous adenomas larger than 2 cm in diameter) should be removed surgically. No further treatment is needed for those without cancerous lesions on postoperative examination; those with cancerous lesions should choose different treatments according to the depth of infiltration. The methods of microscopic resection include trap coagulation method, biopsy forceps coagulation method and electrocoagulator cauterization method. For adenoma with a tip, trap resection is feasible; for broad-based adenoma less than 0.5cm, biopsy clamp coagulation or electrocoagulation method can be used to remove 0.5-1cm broad-based adenoma by trap coagulation method. 2.Surgical resection For villous broad-based adenoma with diameter greater than 2cm, it is not suitable to be resected by colonoscopy in pieces, but should be resected by surgery, generally according to the principles of surgical treatment of colorectal cancer. (1) If the cancer is confined to the mucosal layer, local excision should be adopted, and postoperative colonoscopy should be followed up. (2) If the cancer invades the submucosal layer but does not reach the intrinsic muscular layer, the surgical procedure is usually decided according to the pathological type of adenoma ① Tubular adenoma: if there is no cancer at the cut edge, or if there is no involvement of blood vessels and lymphatic vessels in the section, or if the cancer cells are well differentiated, or if the pathological examination confirms that the adenoma is completely removed, local excision and close follow-up are generally sufficient. (ii) Choroidal adenoma: Since the possibility of lymph node metastasis is as high as 29%-44%, bowel resection including lymph node removal should be performed as usual for colorectal cancer. (3) Mixed adenoma: If it is a tipped type, the treatment principle is the same as that for tubular adenoma when the cancer is limited to the submucosa, and if it is a broad-based type, the treatment principle is the same as that for villous adenoma when the cancer is limited to the submucosa. (3) Radical bowel resection should be performed if the adenoma infiltrates into the muscular layer. The incidence of adenoma and adenocarcinoma of the colon increases with age, with adenoma preceding adenocarcinoma by about 5-10 years, and benign adenoma preceding cancer by an average of 10-12 years in familial polyp syndrome; even in disseminated adenomatous polyps, the polyps develop into cancer at least 4 years, and some reports can be as long as 20 years. The malignancy of adenomas is directly proportional to their size. Muto reported 1.3% malignancy in 2506 cases of adenomas <1 cm, 9.5% malignancy in 1-2 cm, 46.0% malignancy in >2 cm; 4.8% malignancy in tubular adenomas and 40.7% malignancy in villous tubular adenomas. (Muto T, Busseu HJR, Morson BL. The evolution of cancer of colon and rectum. Cancer, 1975;36(4):2551-2552), so endoscopic resection or surgical resection is necessary.