Survival analysis of revised 2013 FIGO staging classification of epithelial ovarian cancer and comparison with previous FIGO staging classification

OBJECTIVE To analyze the prognostic role of revised version of International Federation of Gynecology and Obstetrics (FIGO) stage (2013) in epithelial ovarian cancer and compare with previous version staging classification. METHODS We retrospectively enrolled patients with epithelial ovarian cancer treated at Samsung Medical Center from 2002 to 2012. We reclassified the patients based on the revised FIGO staging classification. RESULTS Eight hundred seventy-eight patients were enrolled (stage I, 22.8%; stage II, 10.4%; stage III, 56.2%; stage IV, 10.7%). Previous stage IC (98, 11.1%) was subdivided into IC1 (9, 1.0%), IC2 (57, 6.4%), and IC3 (32, 4.1%). In addition, previous stage IV (94, 1.7%) was categorized into IVA (37, 4.2%) and IVB (57, 6.5%) in new staging classification. Stage IIC (66, 7.5%) has been eliminated and integrated into IIA (36, 4.1%) and IIB (55, 6.2%) in revised classification. Revised FIGO stage IC3 had significant prognostic impact on PFS (hazard ratio [HR], 3.840; 95% confidence interval [CI], 1.361 to 10.83; P=0.011) and revised FIGO stage IIIC appears to be an independent, significant poor prognostic factor for PFS (HR, 2.541; 95% CI, 1.242 to 5.200; P=0.011) but not in the case of previous version of FIGO stage IIIC (HR, 1.070; 95% CI, 0.502 to 2.281; P=0.860). However, any sub-stages of both previous and revised version in stage II and IV, there was no significant prognostic role. CONCLUSION Revised FIGO stage has more progressed utility for informing prognosis than previous version, especially in stage I and III. For stage II and IV, further validation should be needed in large population based study in the future.