Overall Survival and recurrence free survival comparisons for the propensity score matched cohort. (A) OS comparison for the propensity score matched cohort. The median OS was 2.7 years (CI, 1.6–3.7) in the group that received adjuvant chemotherapy and 2.8 years (CI, 2.0–3.6) in the group that did not receive any postoperative therapy (P=0.421); (B) RFS comparison for the propensity score matched cohort. Median recurrence free survival was 2.2 years (CI, 1.4–3.0) and 2.2 years (CI, 1.8–2.9) for patients who underwent postoperative therapy and for patients who did not receive postoperative treatment, respectively (P=0.515). The hash marks indicate censored events. OS, overall survival; RFS, recurrence free survival.