Prognostic impact of the time interval between primary surgery and start of first-line chemotherapy in patients with advanced ovarian cancer: Analysis of prospective randomized phase III trials

Abstract

5514 Background: Primary surgery followed by platinum-taxane chemotherapy is the standard therapy of advanced ovarian cancer. It is not clear, whether the time interval between surgery and start of first line chemotherapy (time to chemo - TTC) has an impact on the clinical outcome. Methods: Individual patient data meta-analysis of three prospective randomized AGO-OVAR/GINECO trials (AGO OVAR 3, 5, and 7) conducted between 1995 and 2002 to investigate platinum-taxane based chemotherapy regimens in advanced ovarian cancer. Cox proportional hazard models were applied to evaluate the prognostic impact of different variables on survival; TTC was introduced as a continuous variable. Results: A total of 3,326 patients were analyzed. Chemotherapy was started within 8 weeks after surgery. Median progression-free survival (PFS) was 17.91 months (95% CI: 17.15–18.73 months) and median overall survival (OS) 37.83 months (95% CI: 36.57–38.90 months). The median TTC was 19 days (95% CI: 18–19 days, range 1–56 days). By multivariate analysis of the total cohort, there was no significant association between TTC and PFS (p = 0.131) or OS (p = 0.372). In the subgroup of patients with no residual tumor after debulking surgery (n = 1.101), a significant and independent correlation between early start of chemotherapy and improved overall survival was observed (p = 0.022). Conclusions: Our analysis represents the largest study investigating treatment delivery and outcome in ovarian cancer. The time interval between primary surgery and start of first line chemotherapy seems to have no general impact in all patients. However, it could be demonstrated for the first time that a delayed start of chemotherapy was independently associated with decreased overall survival in patients with complete surgical debulking. As previously shown for other biological factors in ovarian cancer, the presence of residual tumor after surgery seems to prevail over the prognostic impact of therapy initiation. No significant financial relationships to disclose.