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 23 days (25th–75th%: 12–33 days). The time interval from surgery to initiation of adjuvant therapy was categorized into three groups: < 2 weeks, 2–4 weeks, and > 4 weeks. 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 < 2 weeks, the hazard ratio for recurrence-free survival was 0.90 (95%CI = 0.59–1.37) for 2–4 weeks and 0.72 (95%CI = 0.46–1.13) for > 4 weeks. 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.