Background: Sphincter-preserving operations (SPO) for lower rectal cancer are on the rise. In the study reported here, we compared the oncologic outcomes of patients who underwent sphincter-preserving operations following preoperative chemoradiation for lower rectal cancer with the outcome for patients who underwent abdominoperineal resection (APR).
Methods: This prospective study included 87 patients who underwent proctectomy with curative intent for locally advanced rectal cancer that was located less than 6 cm from the anal verge. Forty-four patients had APR with no preoperative treatment. Forty-three patients underwent concurrent chemoradiation therapy (CCRT) consisting of preoperative 5-fluorouracil-based chemotherapy and pelvic radiation (4500-5040 cGy); this was followed 6 weeks later by surgery (SPO/CCRT). The oncologic outcomes between the two groups were compared, and factors affecting survival were evaluated.
Results: The median follow-up period was 56.2 months. The overall postoperative complication rates did not significantly differ between SPO/CCRT and APR (32.6% versus 34.2%; p = 0.879). Also, there were no significant differences in the overall recurrence rate (20.9% versus 20.5%; p = 0.956) and 5-year overall survival rate (70.8% versus 62.9%; p = 0.189) between the two groups. By multivariate analysis, only the pathologic N stage was significantly associated with overall survival (p < 0.001).
Conclusions: Sphincter-preserving operation with CCRT could be another option for the treatment of locally advanced lower rectal cancer in patients who are clinically considered for APR, with no deterioration of oncologic outcomes. For patients undergoing curative resection for lower rectal cancer, the pathologic N stage can provide valuable prognostic information about survival.