Prognostic Role of Histological Tumor Regression in Patients Receiving Neoadjuvant Chemotherapy for High-Grade Serous Tubo-ovarian Carcinoma.

Abstract

Our objective was to validate the prognostic role of the chemotherapy response score (CRS), which has been proposed for measuring tumor response to neoadjuvant chemotherapy in patients with high-grade serous tubo-ovarian carcinoma, in predicting progression-free survival (PFS) and overall survival (OS). A retrospective cohort study was conducted of patients with advanced high-grade serous tubo-ovarian carcinoma diagnosed between January 1, 2010, and December 31, 2014, and treated with neoadjuvant chemotherapy. Treatment-related tumor regression was determined according to the 3-tier CRS, and results were compared with standard clinicopathological variables. Survival analysis was performed using Cox proportional hazards models and the log-rank test. Seventy-one patients were eligible for analysis. Median OS was 25.5 months. Fifty-eight patients (82%) had disease recurrence and 32 (45%) had died at study census. Of the 71 patients, 19, 29, and 23 patients had a CRS of 1, 2, and 3, respectively. On univariate analysis, the CRS significantly predicted PFS (hazard ratio [HR], 3.77; 95% confidence interval [CI], 1.83-7.78; P = 0.000) and OS (HR, 2.81; 95% CI, 1.16-6.79; P = 0.022). In a multivariate model, the CRS was significantly associated with PFS (HR, 2.81; 95% CI, 1.16-6.79; P = 0.022) but not with OS (HR, 2.39; 95% CI, 0.47-3.08; P = 0.079). Patients with CRS of 1 and 2 combined were twice as likely to progress during the study period compared with patients with a CRS of 3 (HR, 2.0; 95% CI, 1.06-3.78; P = 0.032; median PFS, 16 vs 26 months). No significant association was observed for OS (CRS 1/2 vs 3; HR, 1.57; 95% CI, 0.68-3.65; P = 0.291). In this study, the CRS showed independent prognostic significance for PFS but not for OS.