METHODS: Our institutional cancer registry data on 266 patients with Stage I epithelial ovarian cancer was reviewed retrospectively and compliance with treatment guidelines for surgery and adjuvant treatment was determined. Patients were categorized according to adherence or non-adherence. The primary endpoints were recurrence-free survival and disease-specific survival. Hazard ratios (HRs) for survival were estimated with a Cox proportional hazards model.
RESULTS: Of the 266 patients, 71 (26.7%) underwent adequate surgical staging in accordance with the guidelines. The guidelines for adjuvant chemotherapy were followed adequately in all 71 patients that were adherent to surgical staging and in 163 of the 195 patients with non-adherence to surgical staging (83.6%). Multivariate analysis, adjusted for prognostic factors, identified higher recurrence-free survival (HR, 0.36; 95% CI, 0.15-0.88) and disease-specific survival (HR, 0.42; 95% CI, 0.16-1.12) among patients whose treatment adhered to both surgical and chemotherapy guidelines, although disease-specific survival was not statistically significant. When excluding clear cell histology from the cohort, the guideline-adherent group had significantly better disease-specific survival than the non-adherent group (HR, 0.13; 95% CI, 0.02-0.94).
CONCLUSIONS: The results of this study suggest that adherence to NCCN guidelines may improve survival outcomes in patients with early-stage epithelial ovarian cancer, particularly in cases other than clear cell histology.