ObjectiveTo observe effect and safety of interstitial chemotherapy with 5-fluorouracil sustained release agent in radical operation of colorectal cancer. MethodsOne hundred and sixty patients with colorectal cancer from October 2011 to December 2013 were randomly divided into observation group and control group according to an incomplete random method, 78 cases of them were in the observation group and 82 cases of them were in the control group. All the patients were performed radical resection of colorectal cancer. The abdominal cavity and pelvic cavity were washed after surgery. 5-fluorouracil sustained release agent was implanted in the observation group patients for interstitial chemotherapy, the implant site was at the tumor resection area and the mesenteric artery. Routine chemotherapy was performed in these two groups after operation. The postoperative complications were observed. The postoperative local recurrence rate, liver metastasis rate, and 24-month survival rate were recorded. ResultsThe rates of abdominal complications and toxic effects had no significant differences between these two groups (P > 0.05). The rates of 12-month and 24-month local recurrence and the rate of liver metastasis in the observation group were significant lower than those in the control group[1.3% (1/78) versus 8.5% (7/82), x2=8.934, P=0.023; 5.2% (4/78) versus 23.2% (19/82), x2=14.834, P=0.004; 10.3% (8/78) versus 18.3% (15/82), x2=12.034, P=0.016]. The rate of 24-month survival in the observation group was significant higher than that in the control group[94.9% (74/78) versus 84.1% (69/82), x2=11.465, P=0.010]. ConclusionThe good safety of interstitial chemotherapy with 5-fluorouracil sustained release agent could effectively decrease local recurrence rate and liver metastasis rate of colorectal cancer after radical operation and improve survival time of patients.