Overall survival analysis.

Abbreviation: HR, hazard ratio; CI, confidence interval; NE, not estimable.aP values for age at diagnosis, CA125 and HER2 amplification ratio were based on Wald test, and P values for all other variables were based on the log-rank test.bBased on Wald test.cTo interpret with caution as there were dDepartures from proportionality assumption. The time-varying effects of receipt of chemotherapy were further accounted for by including a time-by-covariate interaction term in the Cox model. Based on the extended model, there was no significant association between OS and chemotherapy.