The Effect Of Time To Initiating Adjuvant Chemotherapy On Survival In Postoperative Colon Cancer Patients

Objective: Some clinical trials have shown that adjuvant chemotherapy can improve overall survival(OS)of patients with resected colon cancer.The optimum time to initiate adjuvant chemotherapy has not been studied clearly.The present study aimed to explore the relationship between the initiate time of adjuvant chemotherapy and survival in patients with colon cancer.Methods: We retrospectively analyzed 434 cases of II-III colon cancer patients who underwent adjuvant chemotherapy based on fluorouracil after radical resection of colon cancer.The patients were divided into two groups in accordance with the time from surgery to adjuvant chemotherapy,namely,less than 6 weeks and 6-12 week.The primary end point was overall survival,and the secondary end points included disease-free survival.The Cox proportional hazards model was used to analyze the effects of time to initiation of chemotherapy and other clinical covariates on survival.Results: Among the 434 patients,the median time to initiation of adjuvant chemotherapy was 37 days(range 17-83).In the group of less than 6 weeks,there were 285 patients(65.67%)and 149 patients(34.33%)in the group of6-12 weeks.The 5 year survival rates of patients in the group of less than6 weeks and 6-12 weeks were 87.90% and 92.30% respectively(p=0.068).The5 year disease-free survival rates of the patients in two groups were 70.30%and 69.60%,respectively(p=0.378).The results showed that neither overall survival nor disease-free survival was significantly different between patients who initiated adjuvant chemotherapy at 6-12 weeks after surgery and those initiated within 6 weeks.Subgroup analysis indicated that no obvious difference was found between two groups.Multivariate analysis confirmed that age not less than 65 years old,early stage tumor and lower histological grade were good independent prognostic factors for this disease.Conclusions: This retrospective analysis shows that in postoperative colon cancer patients,The results showed that neither overall survival nor disease-free survival was significantly different between patients who initiated adjuvant chemotherapy at 6-12 weeks after surgery and those initiated within 6 weeks.Age not less than 65 years old,early stage tumor and lower histological grade were good independent prognostic factors for this disease.