BACKGROUND Colorectal cancer (CRC) is considered to be a worldwide health 
problem because of its increasing incidence and prevalence. Surgery offers an 
opportunity for cure, but the postoperative recurrence rate is still high 
despite the advancement of chemotherapy. This study aimed to assess the efficacy 
and safety of prolonged capecitabine chemotherapy following CAPOX chemotherapy 
for stage III  CRC after radical surgery. MATERIAL AND METHODS This study 
included 212 patients with stage III CRC undergoing open radical surgery from 
July 2010 to June 2015. Among those patients, 104 patients received prolonged 
capecitabine chemotherapy (prolonged group) following 8 cycles of CAPOX regimen 
chemotherapy, while the other 108 patients (control group) received no prolonged 
chemotherapy. The prolonged chemotherapy consisted of capecitabine (1000 mg/m² 
per day for 2 weeks) and was repeated every 3 weeks for 8 cycles at most. 
Long-term survival and toxicities were retrospectively compared. RESULTS Patient 
characteristics did not differ between the 2 groups. For all patients, no 
significant difference was found in the 3-year disease-free survival (DFS) 
(P=0.7775) or 3-year overall survival (OS) rates between the 2 groups 
(P=0.5787). The prolonged group had significantly higher frequency of hand-foot 
syndrome (P=0.0267) and paresthesia (P=0.0164). In further subgroup analyses, no 
benefit for 3-year DFS or 3-year OS of prolonged capecitabine chemotherapy was 
found in colon cancer or rectal cancer. CONCLUSIONS Prolonged capecitabine 
chemotherapy following CAPOX regimen chemotherapy failed to improve the survival 
of patients with stage III CRC after radical surgery.