title: Surgical management of early colorectal cancer.
abstract: An early colorectal carcinoma is TNM stage T1NxMx. Most early carcinomas of the colon and rectum can be treated by adequate local excision, such as colonoscopic polypectomy and per-anal excision. If there are adverse risk factors, especially poorly differentiated carcinoma, lymphovascular invasion, or incomplete excision, a radical resection is indicated if there is no contraindication. In the case of a low rectal carcinoma, adjuvant chemoradiation should be considered. Recently a new classification has been developed: sm1 is invasion to the upper one-third of the submucosa, sm2 is invasion to the middle one-third, and sm3 is invasion to the lower one-third. Lesions of sm1 and sm2 have a low risk of local recurrence and lymph node metastasis; local excision is adequate. The sm3 lesions and sm2 flat and depressed types have a high risk of local recurrence and lymph node metastasis; further treatment is indicated.
authors.affiliation: Department of Surgery, Mayo Medical School, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: S
authors.initials: S
authors.lastname: Nivatvongs
mesh_terms: D003110:Colonic Neoplasms / Q000145:classification / Q000517:prevention & control / Q000601:surgery; D015179:Colorectal Neoplasms / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D008207:Lymphatic Metastasis; D009361:Neoplasm Invasiveness; D012004:Rectal Neoplasms / Q000145:classification / Q000473:pathology / Q000601:surgery; D012307:Risk Factors