Carbognin L, Sperduti I, Ciccarese M, Fabi A, Petrucelli L, Vari S, Forcignanò RC, Nortilli R, Vicentini C, Pilotto S, Merler S, Zampiva I, Brunelli M, Manfrin E, Giannarelli D, Tortora G, and Bria E
Background: The aim of this analysis was to develop and validate a prognostic model for advanced breast cancer (ABC) with luminal subtype based on the combination of clinical, pathological and therapeutic predictors to provide a practical tool to evaluate patients' prognosis., Methods: Clinical and pathological data were retrospectively correlated to progression-free and overall survival (PFS/OS) using a Cox model. Significant treatment variables were adjusted with the propensity score analysis. A continuous score to identify risk classes was derived according to model ratios. The performance of the risk-class model was tested for post-progression survival (PPS) and conditional survival (CS) as well., Results: Data from 335 patients (3 institutions) were gathered (median follow-up 58 months). At multivariate analysis Ki67, Performance Status (PS) and number of metastatic sites were significant predictors for PFS, whereas Ki67, PS, brain metastases, PFS after 1st-line therapy, number of chemotherapy lines, hormonal therapy and maintenance were significant predictors for OS. The hormonal maintenance resulted to be prognostic after adjustment with propensity score analysis. A two-class model significantly differentiated low-risk and high-risk patients for 2-year PFS (31.5% and 11.0%, p < 0.0001), and 3-years OS (57.1% and 4.8%, p < 0.0001). A three-class model separated low risk, intermediate-risk, and high-risk patients for 2-year PFS (40.8%, 24.4%, and 11.0%, p < 0.0001) and 3-year OS (68.1%, 24.8%, and 4.8%, p < 0.0001). Both models equally discriminate the luminal ABC prognosis in terms of PPS and CS., Conclusions: A risk stratification model including 'easy-to-obtain' clinical, pathological and therapeutic parameters accurately separates luminal ABC patients into different risk classes., (Copyright © 2016 Elsevier Ltd. All rights reserved.)