TOTAL MESENTERIC EXCISION IN THE SURGICAL-TREATMENT OF RECTAL-CANCER - A PROSPECTIVE-STUDY

Background: Total mesorectal excision has been advocated in conjunctio n with low anterior or abdominoperineal resection as the optimal surgi cal treatment for rectal cancer. It involves removal of the entire rec tal mesentery as an intact unit and maximizes the likelihood of obtain ing a negative circumferential margin. Objectives: To prospectively va lidate the efficacy of total mesorectal excision in obtaining locoregi onal control, to identify the perioperative factors influencing the se lection of either a sphincter sparing or a sphincter ablating procedur e, and to identify independent factors that may influence long-term pr ognosis in rectal cancers. Settings: Tertiary referral center. Patient s: Seventy-three consecutive patients with rectal cancer located withi n 10 cm of the anal verge were treated from 1984 to 1997 by the senior author (F.M.). Sixty-five patients form the basis of our analysis aft er the exclusion of 7 patients who had their cancer removed transanall y and 1 patient who had a permanent diverting stoma as the only proced ure. Results: Twenty-six patients underwent a sphincter ablating proce dure; 39 underwent a sphincter sparing procedure. Operative mortality was 1.5%. Follow-up was complete in 64 patients (39+/-30 months; range , 3-126 months). Five-year actuarial survival rates were 88% for the 3 4 patients with stage I and II adenocarcinoma and 65% for the 22 patie nts with stage III adenocarcinoma. The local recurrence rate was 6.2% overall, but only 3.1% in the potentially curable group (stages I-III) . When only patients who did not receive adjuvant chemoradiation thera py were considered (n=23), local recurrence rate was 8.3% overall and 0% in the potentially curable group. Tumor stage (P=.04) and vascular and/or lymphatic invasion (P=.002) were statistically significant in t heir association with survival. Circumferential lesions (P<.001), gros s invasion of contiguous organs (P<.001) and distance from the anal ve rge of less than 5 cm (P=.01) were statistically significant in their association with the choice of a sphincter ablating procedure. Conclus ions: This study confirms the efficacy of total mesorectal excision in minimizing locoregional recurrence rates and confirms the well-establ ished prognostic value of stage and microinvasion. Moreover, it indica tes that circumferential lesions, distance from anal verge, and gross invasion of contiguous organs are significant perioperative factors in the selection of the type of surgical procedure.