Purpose: Although sphincter-preservation procedures have replaced abdominoperineal resection as the treatment of choice for rectal cancer, a subset of patients with rectal cancer will still require abdominoperineal resection. The use of adjuvant radiotherapy has been shown to reduce local recurrence, and combined modality therapy (chemoradiation) improves survival. Sharp mesorectal excision compared with the classic teaching of blunt retrorectal dissection is also an important component of local control. The primary aim of the present study was to evaluate the postoperative complications associated with neoadjuvant therapy in patients requiring complete rectal excision. Oncologic outcomes for all patients with abdominoperineal resection are also provided.
Methods: A prospective database of 5,634 patients who underwent surgery for colorectal cancer at Memorial Sloan-Kettering Cancer Center between the years 1987 and 1997 was reviewed. Patients with primary adenocarcinoma of the rectum who underwent abdominoperineal resection were identified. In 1,622 patients who were operated on for primary rectal cancer, 292 patients (18 percent) underwent abdominoperineal resection and the rest had a sphincter-preserving procedure. Ten patients were excluded from the study because of prior pelvic irradiation for other cancer (8 patients) and insufficient radiation dose (<4,000 cGy; 2 patients). Neoadjuvant radiotherapy was given to 123 patients and postoperative adjuvant radiotherapy to 65 patients, whereas 94 did not receive radiotherapy. Intraoperative radiotherapy combined with preoperative radiotherapy was administered to 23 of the 123 patients given neoadjuvant radiotherapy.
Results: The duration of the operation was significantly longer in both neoadjuvant radiotherapy and intraoperative radiotherapy groups compared with the nonradiotherapy group (P = 0.01 and P < 0.0001, respectively). Estimated blood loss, mean number of blood units transfused per patient, and the percentage of patients being transfused were similar among the groups. Early postoperative complications were significantly higher in the neoadjuvant radiotherapy groups compared with the nonradiotherapy group. Late complications, overall survival, disease-free survival, and local recurrence were not significantly different among the groups.
Conclusions: In patients with cancer of the lower one-third of the rectum, sharp pelvic dissection can result in a low rate of local recurrence even without radiotherapy. The role of preoperative radiotherapy, although associated with higher perineal wound complications, is important in increasing resectability and sphincter-preservation rate. Randomized, prospective trials will be needed to establish the role of adjuvant radiotherapy in patients undergoing sharp mesorectal excision for rectal cancer.