Abstract: Objective To investigate the feasibility and safety of the double cavity casing negative pressure drainage by inside and outside of the intestine in the primary resection and anastomosis of low rectal cancer. Methods A total of 650 cases with low rectal cancer treated in our hospital from January 2009 to December 2014 were retrospectively collected and divided into control group (n=220), stoma group (n=205) and drainage group (n=225). The control group was received Dixon (low rectal anterior resection), the stoma group was treated with Dixon and ileostomy, while the drainage group was underwent double cavity casing negative pressure drainage by inside and outside of the intestine in the primary resection and anastomosis. The operation time, bleeding volume, the period of anal exhaust after operation and hospital expenses were compared between three groups. Postoperative follow- up was performed, and anastomotic leakage, postoperative infection and other complications were analyzed. Results There were no significant differences in the operation time, bleeding volume and the period of anal exhaust after operation between three groups (P > 0.05). The hospital stay and expenses were shorter and lower in drainage group than those in stoma group (P < 0.05). In addition, there were no significant differences in wound infection, pelvic infection, and pulmonary infection between three groups (P > 0.05). All patients were followed up, and the mortality, the recurrence rate and metastasis rate were not significantly different between three groups (P > 0.05). Conclusion The application of double cavity casing negative pressure drainage is likely to reduce the incidence of anastomotic leakage in Dixon, while the effect needs to be confirmed by large clinical trial， at the same time, patients enjoy shorter hospital stay, fewer suffering and lower expense of hospitalization.

Key words: rectal neoplasms, anastomosis, surgical, drainage, postoperative complications, low rectal cancer, Dixon operation, double cavity casing, anastomotic leakage