The efficacy of primary progesterone on survival in early breast cancer: A real world scenario.

Abstract

e12522 Background: Surgery performed during progestogenic milieu improves survival in breast cancer patients. We previously proved efficacy of pre-operative progesterone in high-risk, operable breast cancer. In another multicenter randomized trial, intra-operative peri-tumoral local anesthetic injection showed 29% reduction in mortality. In this study, several patients had also received progesterone injection since this is adopted as standard of care across some centers including ours. We assessed the effectiveness of pre-operative progesterone in patients who were randomized in the local anesthetic study. Methods: We analyzed 1583 patients randomized on the local anesthetic study during December 2011-October 2018 with respect to receipt of progesterone. All patient who had breast lump of ≥2cm and/or node positive were eligible to receive progesterone injection before surgery. Kaplan Meier curves were plotted along with Cox regression analysis to study factors affecting disease-free and overall survival. Results: Of 1583, 454 patients did not receive, and 1129 patients received progesterone before surgery. The median age of whole cohort was 51 years, median pT size was 3 cm, 45% were node positive, 60% ER/PR+ and 24%TNBC. At median follow-up of 68 (0·5-72) months in surviving patients, there were a total of 292 DFS events (progesterone arm-193, no-progesterone arm-99). The 5-year disease-free survival (DFS) was 86.5% in the progesterone arm and 79.2% in the no-progesterone arm (HR-0.57,0.45-0.73, P<0.001). The 5-year overall survival (OS) was 90.5% in the progesterone arm and 82.8% in the no-progesterone arm (HR-0.47,0.36-0.63,P<0.001). On Cox Regression analysis (Table), administration of progesterone injection was an independent prognostic factor for DFS (HR-0.53,0-41-0.70, p<0.001) and OS (HR-0.44,0-32-0.60, p<0.001) both. Conclusions: The receipt of pre-operative progesterone improved outcomes in the setting of another randomized trial. It should be administered to all high risk (T2/N1) breast cancer patients who are planned for surgery first. [Table: see text]