The association between timing of initiation of adjuvant therapy and the survival of early stage ovarian cancer patients - An analysis of NRG Oncology/Gynecologic Oncology Group trials

Abstract

Objectives: To determine the association between timing of adjuvant therapy initiation and survival of early stage ovarian cancer patients.

Methods: Data were obtained from women who underwent primary surgical staging followed by adjuvant therapy from two Gynecologic Oncology Group trials (protocols # 95 and 157). Kaplan-Meier estimates and Cox proportional hazards model adjusted for covariates were used for analyses.

Results: Of 497 stage I-II epithelial ovarian cancer patients, the median time between surgery and initiation of adjuvant therapy was 23days (25th-75th%: 12-33days). The time interval from surgery to initiation of adjuvant therapy was categorized into three groups: <2weeks, 2-4weeks, and >4weeks. The corresponding 5-year recurrence-free survival rates were 72.8%, 73.9%, and 79.5% (p=0.62). The 5-year overall survival rates were 79.4%, 81.9%, and 82.8%, respectively (p=0.51; p=0.33 - global test). As compared to <2weeks, the hazard ratio for recurrence-free survival was 0.90 (95%CI=0.59-1.37) for 2-4weeks and 0.72 (95%CI=0.46-1.13) for >4weeks. Age, stage, grade, and cytology were important prognostic factors.

Conclusions: Timing of adjuvant therapy initiation was not associated with survival in early stage epithelial ovarian cancer patients.

Keywords: Early stage ovarian cancer; Prognosis; Survival.