Objective Ovarian cancer is the deadliest of gynecologic cancers. In recent years, International Federation of Gynecology and Obstetrics (FIGO) and the World Health Organization (WHO) classifications were revised. We compared the major changes between the classifications and examined the effects on the therapy and prognosis of the ovarian, fallopian tubes, and peritoneum cancer in our series according to both classifications.

Methods/Materials We performed an observational descriptive study of 210 patients who were diagnosed with a malignant ovarian tumor from 2010 to 2016. The accepted FIGO and WHO classifications at each point in time were registered. We reclassified both data, obtaining both classifications for each patient. The changes in the therapeutic management and prognosis were examined.

Results In both FIGO classifications of our case series, most patients with ovarian cancer were in FIGO stage III. We found that 4.2% of the previous stage IIIC patients have changed to stage IIIA2 or stage IIIB, with better prognosis and survival rate. In the new WHO classification, the main change, in our case series, was the increase in the high-grade serous carcinoma percentage. According to the current recommendations, we observed 7.56% more patients in early ovarian cancer stages treated with platinum and taxane. In both early and advanced ovarian cancer group, high-grade serous carcinoma tumors were predominant.

Conclusions The newly created WHO and FIGO classifications have improved the ability to predict the prognosis and consequently to change the therapeutic managements of patients with ovarian cancer.