Stage IIIC epithelial ovarian cancer classified solely by lymph node metastasis has a more favorable prognosis than other types of stage IIIC epithelial ovarian cancer.

OBJECTIVE To verify whether it can be justified to classify patients to stage IIIC epithelial ovarian cancer based on nodal involvement only. METHODS This study included all consecutive patients with stage IIIC epithelial ovarian cancer who underwent upfront cytoreductive surgery according to the FIGO guideline followed by platinum based chemotherapy from September 1989 to September 2006 at Asan Medical Center. RESULTS During the study period, a total of 272 patients met the inclusion criteria. Optimal cytoreduction was achieved in 213 patients, and complete cytoreduction was achieved in 85 patients. Median follow-up time was 37 months (range, 6-181 months). The 5-year disease free survival (DFS) and overall survival (OS) rate of all patients were 23% and 57%, respectively. Forty-one patients were allocated to stage IIIC by positive nodes only. Patients with stage IIIC disease due to positive nodes only had significantly longer DFS and OS compared to other stage IIIC patients (p<0.001 and p<0.001). The DFS and OS of these patients was significantly better than those of other stage IIIC patients who achieved complete or optimal cytoreduction (p<0.001 and p<0.001). The outcome was even better than that of stage IIIA and IIIB patients (p<0.05 and p<0.05). CONCLUSION Patients with stage IIIC epithelial ovarian cancer due to positive nodes only had a more favorable prognosis compared to other stage IIIC patients. Therefore, reevaluation of the current FIGO staging system for stage IIIC epithelial ovarian cancer is required.