Surgical treatment of adenocarcinoma of the rectum

The authors' aim was to determine survival and recurrence rates in patients undergoing resection of rectal cancer achieved by abdominoperineal resection (APR), coloanal anastomosis (CAA), and anterior resection (AR) without adjuvant therapy.

The surgery of rectal cancer is controversial; so, too, is its adjuvant management. Questions such as preoperative versus postoperative radiation versus no radiation are key. An approach in which the entire mesorectum is excised has been proposed as yielding low recurrence rates.

Of 1423 patients with resected rectal cancers, 491 patients were excluded, leaving 932 with a primary adenocarcinoma of the rectum treated at Mayo. Eighty-six percent were resected for cure. Surgery plus adjuvant treatment was performed in 418, surgery alone in 514. These 514 patients are the subject of this review. Among the 514 patients who underwent surgery alone, APR was performed in 169, CAA in 19, AR in 272, and other procedures in 54. Eighty-seven percent of patients were operated on with curative intent. The mean follow-up was 5.6 years; follow-up was complete in 92%. APR and CAA were performed excising the envelope of rectal mesentery posteriorly and the supporting tissues laterally from the sacral promontory to the pelvic floor. AR was performed using an appropriately wide rectal mesentery resection technique if the tumor was high; if the tumor was in the middle or low rectum, all mesentery was resected. The mean distal margin achieved by AR was 3 +/- 2 cm.

Mortality was 2% (12 of 514). Anastomotic leaks after AR occurred in 5% (16 of 291) and overall transient urinary retention in 15%. Eleven percent of patients had a wound infection (abdominal and perineal wound, 30-day, purulence, or cellulitis). The local recurrence and 5-year disease-free survival rates were 7% and 78%, respectively, after AR; 6% and 83%, respectively, after CAA; and 4% and 80%, respectively, after APR. Patients with stage III disease, had a 60% disease-free survival rate.

Complete resection of the envelope of supporting tissues about the rectum during APR, CAA, and AR when tumors were low in the rectum is associated with low mortality, low morbidity, low local recurrence, and good 5-year survival rates. Appropriate "tumor-specific" mesorectal excision during AR when the tumor is high in the rectum is likewise consistent with a low rate of local recurrence and good long-term survival. However, the overall failure rate of 40% in stage III disease (which is independent of surgical technique) means that surgical approaches alone are not sufficient to achieve better long-term survival rates.