Introduction/Background Neoadjuvant chemotherapy (NAC) has increased as first-line therapy in advanced high-grade serous ovarian carcinoma (HGSOC). However, several studies reported NAC-induced platinum resistance. This study was aimed at evaluating the predictive impact of clinical factors on CRS and selecting patients who would respond well to NAC.

Methodology This multicenter, retrospective study included patients between January 2016 and December 2021. FIGO stage III and IV HGSOC patients were eligible. Institutionally strict complete resectability criteria were used. Pathology slides were scored according to CRS criteria.

Results Among 172 HGSOC patients, 87 (50.6%) had stage IIIC disease, and 85 (49.4%) had stage IV. And 35 (20.4%) were CRS1, 103 patients were CRS2 (59.9%), and 34 patients were CRS3 (19.7%). Compared to CRS1, simultaneous metastases to distant LNs and solid organs confirmed by imaging were associated with a 75% reduction in CRS2 (odds ratio (OR) = 0.25; 95% CI: 0.09 - 0.70; P = 0.008). And BRCA 1/2 mutation was positively (OR = 8.41; 95% CI: 2.25 – 31.52; P = 0.002) associated with CRS3 compared to CRS1. Patients with CRS3 had significantly longer progression-free survival (PFS), with median PFS of 9.8, 14.8, and 27.0 months for CRS of 1, 2, and 3, respectively (P = 0.001). Overall survival (OS) was also prolonged for patients with CRS3 (P = 0.001).

Conclusion Germline BRCA 1/2 mutation was a predictor of CRS3 and a good prognostic factor for survival rate. Simultaneous metastases to distant LNs and solid organs were predictors of CRS1. CRS were inversely correlated with PFS and OS.

Disclosures I have no disclosure at all.