Abstract P3-07-56: Predictive value of tertiary lymphoid structure assessed by high endothelial venule count in neoadjuvant setting of triple-negative breast cancer

Background Tertiary lymphoid structure (TLS) is an ectopic lymph node-like structure characterized by lymphoid aggregation with high endothelial venules (HEVs), and is an important source of tumor-infiltrating lymphocytes (TILs). TILs have a strong prognostic and predictive significance, particularly in triple-negative breast cancer (TNBC). We previously analyzed expression of immune-related genes in pre-neoadjuvant chemotherapy (NAC) biopsy samples using NanoString assay and showed that gene expression of follicular helper T cell marker CXCL13 , which is closely associated with TLSs, was an independent predictive factor for pathologic complete remission (pCR) in TNBC. However, measuring gene expression of biopsy sample is not easy to perform in daily pathology practice. Therefore, we evaluated TLSs by assessing hematoxylin and eosin (HE San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-56.