[Efficacy of preoperative radiotherapy combined with total mesorectal excision in the treatment of locally resectable rectal cancer: a systematic review].

OBJECTIVE: To assess the clinical efficacy of preoperative radiotherapy combined with total mesorectal excision (TME) in the treatment of locally resectable rectal cancer.

METHODS: Literature search was carried out to identify prospective clinical randomized controlled trails on preoperative radiotherapy for rectal cancer published from January 1982 to April 2009. The basic characteristics and clinical efficacy of the trials meeting the screening criteria were enrolled. Date analysis was performed by RevMan 4.2.

RESULTS: According to the selection criteria, 9 clinical trials were included. Compared with surgery alone, the short-term preoperative radiotherapy was associated with reduced 2-year local recurrence rate (2.4% vs 8.2%, P<0.01). There were no significant differences in 4-year overall survival (67.2% vs 66.2%), 4-year disease-free survival (58.4% vs 55.6%) and local recurrence (RR=1.16, 95% CI:0.37~3.61, P=0.80) between the preoperative radiotherapy and radiochemotherapy. High-dose preoperative radiotherapy could increase the complete response rate and sphincter sparing surgery rate than that low-dose (16.0% vs 2.0%, P<0.05). The interval between preoperative radiotherapy and operation did not affect the overall survival, disease-free survival and local recurrence.

CONCLUSION: Preoperative radiotherapy combined with total mesorectal excision is associated with lower local recurrence.