The revised 2014 FIGO staging system for epithelial ovarian cancer: is a subclassification of FIGO stage IV justified?

Objective: The revised 2014 FIGO staging system for epithelial ovarian cancer (EOC) included many changes of the previous system, particularly dividing FIGO stage IV in two subgroups. We evaluated if stratifying patients with EOC in FIGO stage IVA and IVB has any prognostic implication.

Patients and methods: We analyzed our prospectively maintained institutional database for primary EOC and included only consecutive FIGO stage IV patients treated between 2000 and 2014. Patients were stratified in two cohorts: FIGO IVA and FIGO IVB. Patients with abdominal-wall-metastasis as the only manifestation of distant metastasis were excluded (n = 86). Survival analyses included the Kaplan-Meier method, log-rank test and Cox proportional hazards models.

Results: In total, 240 consecutive patients with FIGO stage IV disease were identified. According to the new classification 102 (42.5%) and 138 (57.5%) patients were classified into FIGO IVA and FIGO IVB, respectively. In 45 of 138 (32.6%) patients with FIGO stage IVB at least two or more metastatic manifestations were detected. Median overall survival was 25 and 28 months in FIGO IVA and IVB (p = 0.299), respectively. In multivariate analysis, only performance status, lymph node status, ascites volume and residual tumor after surgery, but not FIGO stage IV subgroups were significantly associated with overall survival.

Conclusion: In the present analysis, the revised FIGO system for stage IV did not add prognostic information for patients with FIGO IVA or FIGO IVB. Further analyses should try to confirm or challenge this particular part of the new FIGO system.