Statistical Analysis

PASS version 15.0.5 (NCSS LLC., USA) was used for the sample size calculation. The 3-year disease-free survival (DFS) rate of stage III colon cancer patients after surgery in control group was estimated to be 68% (14, 15). Chemotherapy plus PRM1201 increased DFS to 79% in the adjuvant treatment of colon cancer and using an α value of 5% and power (1-β) of 80%, we calculated that a sample size of 327 was required. In consideration of a 10% loss rate in follow-up, there were a total of 364 cases needed in this study.

SPSS version 21.0 (IBM Corp., Armonk, USA) was used for the statistical analysis. DFS was compared using a two-sided log-rank test. Hazard ratios with 95% confidence intervals were calculated using the Cox proportional hazards model. The Kaplan–Meier method was used to draw survival curves. Standard parametric or non-parametric tests were used for continuous factors and χ2 tests were used for categorical factors. Continuous variables were presented as means (SD) and medians (interquartile range [IQR]). A value of P < 0.05 was considered significant.