Kaplan-Meier analysis and Cox regression analysis results
The results of Kaplan-Meier analysis and multivariate analyses performed to identified the prognostic factors for PFS are shown in Table 3. Kaplan-Meier analysis indicated that histopathological subtype (P = 0.01), a positive result of interim PET/CT when using DC-3 ((P = 0.02, Fig. 1A), a positive result of post-treatment PET/CT when using IHPC ((P<0.01, Fig 1B), DC-3 (P<0.01, Fig 1C) and DC-4 (P<0.01, Fig 1D) were associated with worse PFS. Variables with P<0.05 in univariate analysis were incorporated into multivariate Cox regression analysis and the results showed that only DC-4 was an independent prognostic factor for PFS (P < 0.01, hazard ratio: 7.82, 95% CI: 2.65–23.05).