Objectives: The objective of this study was to determine whether the length of the interval from primary surgery to commencement of chemotherapy has any direct effect on progression-free survival in ovarian cancer.
Methods: The progression-free survival of 472 patients enrolled in four trials who had all received platinum-containing chemotherapy (either in combination with a taxane or cyclophospamide) was subjected to univariate analysis. Dividing subjects into those above and below the median interval from surgery to chemotherapy formed two groups for analysis. The analysis was stratified by study and arm/cohort within study to remove any possible influence of the different studies and study doses. Multivariate analysis was then performed including stage, bulk of residual disease, and performance status as well as interval to starting chemotherapy.
Results: The median interval from surgery to chemotherapy was 22 days (range 7-100). Univariate analysis of the above median and below median groups showed worse progression-free survival for those with earlier treatment (hazard ratio 0.84, P = 0.14, 95% CI 0.67-1.06); however, those treated earlier tended to have bulkier residual disease (>2 cm; P = 0.006). When multivariate analysis was performed incorporating residual disease status, FIGO stage, and performance status, the hazard rate ratio for interval to surgery was 0.99 (P = 0.91, 95% CI 0.79-1.24).
Conclusions: This study suggests that the interval from surgery to commencement of chemotherapy is not an independent prognostic factor for progression-free survival.