Sphincter preservation in rectal cancer. Technical considerations for coloanal anastomosis and J-pouch.
Most patients with midrectal cancer undergo a sphincter-preserving operation using modern bowel stapling techniques. In patients with bulky tumors or unfavorable pelvic anatomy, however, abdominoperineal resection with permanent colostomy may be performed for technical reasons, not based on oncologic clearance needs. In addition, low-lying tumors treated initially with preoperative chemoradiation are often downstaged, increasing the opportunity for restorative procedures. Treatment by total proctectomy and peranal sutured coloanal reconstruction fulfills the need for adequate oncologic clearance and satisfactory bowel function. Sharp pelvic dissection with removal of the entire rectal mesentery, adequate mobilization of the left colon, and precise anastomotic technique are required for optimal results. Creation of a colon J-pouch increases the capacity of the reconstructed rectum and greatly reduces the time required for functional adaptation in the postoperative period. Although irregular evacuation and other minor problems can persist, permanent colostomy is avoided, and patient satisfaction is high. For cancers of the middle and distal rectum, total proctectomy with coloanal reconstruction is an important treatment option that can improve quality of life without compromising cancer treatment.