Introduction/Background Neoadjuvant chemotherapy (NACT) followed by surgery has been shown to be an alternative treatment in patients with advanced ovarian cancer who are unlikely to achieve optimal cytoreduction with primary surgery. Successful stratification tools have been created to determine cytoreduction prognosis. The Chemotherapy Response Index is intended to be one of them.

Objective To evaluate the impact on overall survival at 3 and 5 years of patients treated with NACT according to the Chemotherapy Response S core (CRS).

Methodology Retrospective analysis of a longitudinal cohort study. All patients diagnosed with FIGO stage IIIC ovarian cancer who received NACT followed by surgery as treatment during the study period 2017–2022 were included. All patients received between 4–6 cycles of chemotherapy, carbo-taxol schedule followed by surgery. CRS score was analyzed in all of them. A CRS score 1 and 2 indicated partial chemotherapy response while CRS score 3 indicated very good response to chemotherapy. 3- and 5-year survival was analyzed according to the CRS score.

Results A total of 57 patients met the inclusion criteria, representing 40.7% of all stage IIIC ovarian cancers in that period. The mean age of the patients was 62 years, and 75.4% were menopausal. The most frequent tumor type was serous carcinoma (93%). A CRS 1–2 was present in 80.7% (n= 46).

Clinicopathological characteristics were compared between the CRS 1–2 and CRS 3 groups and no statistically significant differences were found between the two groups.

Survival of patients at 3 and 5 years in the CRS 3 group was 100%, while in the CRS 1–2 group it was 68.9% and 53.3% respectively, these differences being statistically significant (Long Rack of 0.04 and 0.009).

Conclusion In our study, presenting a CRS 3 after treatment with NACT followed by surgery is a good prognostic factor with a 3- and 5-year survival of 100%.

Disclosures No disclosures