Fig. 1

Comparison of survival probability. A and B show survival probabilities before and after propensity score matching, respectively. The Kaplan–Meier method (log-rank test) was used to compare the survival probability of the groups, which were classified by body weight. Patients with low body weight (< 67.2 kg) are represented with a blue line, whereas patients with high body weight (≥ 67.2 kg) are indicated by a red line. The median survival times for patients with low and high body weight were 1020 days (95% confidence interval [CI], 738–1302) and 1693 days (95% CI, 910–2476), respectively (A). Furthermore, the results after propensity score matching were similar to those before propensity score matching, with significantly longer survival time in patients with high body weight (B). *p < 0.05