Methods and results of sphincter-preserving surgery for rectal cancer.

BACKGROUND Sphincter preservation is the goal in the treatment of rectal cancer and should be considered in all patients with an intact sphincter. Sphincter preservation for tumors of the upper rectum is easily achieved, but surgical management of cancer of the mid and lower third of the rectum continues to evolve. Several recent advances may influence future treatment strategies. METHODS We reviewed the literature to identify the current methods of sphincter-preserving surgery and their oncologic and functional results. RESULTS Proctectomy with total mesorectal excision reduces the incidence of local recurrence to less than 10% while preserving genitourinary function. The use of preoperative radiotherapy may further diminish the risk of local recurrence. In selected patients, partial resection of the anal sphincter may avoid definitive colostomy without compromising oncologic outcome. In contrast, the role of local resection of rectal cancer remains controversial. Restoration of continuity by means of a colonic reservoir reduces stool frequency and urgency and improves continence when compared to a straight coloanal anastomosis. The transverse colpoplasty pouch may allow pouch construction in patients in whom it is currently impossible, but long-term follow-up is not yet available. CONCLUSIONS Sphincter-preserving surgery is possible for the majority of patients with rectal cancer. Optimal functional results may be obtained by a nerve-sparing operative technique and by use of a colonic reservoir for reconstruction following resection of mid or low rectal cancers.