The aim of the study was to evaluated the prognostic significance of TIL subtypes (CD4+, CD8+, FOXP3+ T cells) and their location (stromal "s" and intratumoral "i" CD4+ and CD8+) in BC patients, focusing on the association between these markers and immunocheckpoint molecules such as cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed cell death ligand 1 (PD-L1) and its receptor (PD-1).
The changes in T cell subsets and programmed death ligand 1 (PD-L1) expression during the transition from ductal carcinoma in situ (DCIS) to early invasive breast cancer had not been well studied.
Multicolor immunohistochemical multiplex assays simultaneously demonstrating PD1, PD-L1, and CD8 or PD-L1, CD3, and CD163 were performed on tissue microarrays (TMA) representing 216 pretreatment cases of HER2-positive invasive breast carcinoma.
We validated the identified gene signature related to radiosensitivity and analyzed the PD-L1 status of invasive breast cancer in The Cancer Genome Atlas (TCGA) dataset.