Abstract 4309: A novel immune prognostic index for the stratification of high-risk patients with early breast cancer

Abstract

Abstract The prognostic or predictive value of current commercial multigene assays for breast cancer are limited to hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer. Despite the prognostic or predictive significance of immune response-related genes in breast cancer, immune gene signatures have not been incorporated into most current assays. Here, we developed a novel immune gene based-prognostic model to predict the risk of recurrence in high-risk women with early breast cancer. Using public gene expression microarray datasets for breast cancer, we classified breast cancer patients into three risk groups according to clinical risk and proliferation risk, and identified the most significant five immune response-related genes (TRAT1, IL2RB, CTLA4, IGHM and IL21R) associated with clinical outcome in the clinical and proliferation high-risk (CPH) subgroup. Immune prognostic index based on the combination of the expression of five immune response-related genes and lymph node status was developed to predict the risk of recurrence in high-risk breast cancer patients and its prognostic significance was validated in independent validation datasets. Disease-free survival (DFS) or distant metastasis-free survival (DMFS) of patients classified as high risk according to the immune prognostic index was significantly lower than those of patients classified as intermediate and low risk in the CPH group. Multivariate analysis demonstrated that the immune prognostic index is an independent prognostic factor for DFS or DMFS. Moreover, c-index showed that the immune prognostic index is superior to clinicopathological variables in predicting the prognosis. Our immune index was also prognostic in independent validation datasets. Our immune prognostic index identified low-risk patients among patients classified as CPH group in all molecular subtypes of breast cancer and may be used to overcome the limitations of the current multigene assay. Citation Format: Hannah Lee, Mi Jeong Kwon, Beom-Mo Koo, Jinil Han, Young Kee Shin. A novel immune prognostic index for the stratification of high-risk patients with early breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4309.