Anterior resection for rectal cancer with mesorectal excision - A prospective evaluation of 622 patients

Objective: This study aims to review the operative results and oncological outcomes of anterior resection for rectal and rectosigmoid cancer. Comparison was made between patients with total mesorectal excision (TME) for mid and distal cancer and partial mesorectal excision (PME) for proximal cancer, when a 4- to 5-cm mesorectal margin could be achieved. Risk factors for local recurrence and survival were also analyzed. Summary Background Data: Anterior resection has become the preferred treatment option rectal cancer. TME with sharp dissection has been shown to be associated with a low local recurrence rate. Controversies still exist as to the need for TME in more proximal tumor. Methods: Resection of primary rectal and rectosigmoid cancer was performed in 786 patients from August 1993 to July 2002. Of these, 622 patients (395 men and 227 women; median age, 67 years) underwent anterior resection. The technique of perimesorectal dissection was used. Patients with mid and distal rectal cancer were treated with TME while PME was performed for those with more proximal tumors. Prospective data on the postoperative results and oncological outcomes were reviewed. Risk factors for anastomotic leakage, local recurrence, and survival of the patients were analyzed with univariate and multivariate analysis. Results: The median level of the tumor was 8 cm from the anal verge (range, 2.5-20 cm) and curative resection was performed in 563 patients (90.5%). TME was performed in 396 patients (63.7%). Significantly longer median operating time, more blood loss, and a longer hospital stay were found in patients with TME. The overall operative mortality and morbidity rates were 1.8% and 32.6%, respectively, and there were no significant differences between those of TME and PME. Anastomotic leak occurred in 8.1% and 1.3% of patients with TME and PME, respectively (P < 0.001). Independent factors for a higher anastomotic leakage rate were TME, the male gender, the absence of stoma, and the increased blood loss. The 5-year actuarial local recurrence rate was 9.7%. The advanced stage of the disease and the performance of coloanal anastomosis were independent factors for increased local recurrence. The 5-year cancer-specific survival was 74.5%. The independent factors for poor survival were the advanced stage of the disease and the presence of lymphovascular and perineural invasion. Conclusions: Anterior resection with mesorectal excision is a safe option and can be performed in the majority of patients with rectal cancer. The local recurrence rate was 9.7% and the cancer-specific survival was 74.5%. When the tumor requires a TME, this procedure is more complex and has a higher leakage rate than in those higher tumors where PME provides adequate mesorectal clearance. By performing TME in patients with mid and distal rectal cancer, the local control and survival of these patients are similar to those of patients with proximal cancers where adequate clearance can be achieved by PME.