Surgical resection of the colon and/or the rectum is most often done for cancer, diverticular disease, obstruction or ischemia. Traditionally, it is performed through a midline incision, though we see an increased trend for laparoscopic cases. The extent of surgical resection is determined by the location of the lesion to be removed and the regional distribution of lymph nodes in cancer cases. The general term “colectomy” includes (a) right hemicolectomy, (b) transverse colectomy, (c) left hemicolectomy, (d) sigmoid colectomy and total colectomy — the difference being anatomical location.
A low anterior resection (LAR) is the removal of the proximal portion of the rectum and the mid portion of the sigmoid colon. An abdominoperineal resection (APR) is the removal of the rectum and the distal sigmoid colon.