Clinicopathological significance of the immunologic signature (PDL1, FOXP3+ Tregs, TILs) in early stage TNBC treated with neoadjuvant chemotherapy

Abstract Patients with breast cancer are appropriate candidates for neoadjuvant chemotherapy (NAC) to facilitate conservative surgery. The chemotherapeutic agents may exert their action by inducing the anti-tumor immune response. This study aimed to evaluate the tumor immune microenvironment including PD-L1, Foxp3+ Tregs, and TILs count in early stages TNBC patients (stage T1, T2) before and after neoadjuvant chemotherapy and their correlation with the clinical and pathological response. Fifty patients of TNBC patients were enrolled in this study; all of them received neoadjuvant chemotherapy. TILs count, Foxp3+ Tregs, and PD-L1 immunohistochemical expression were investigated in all cases before NAC and then evaluated in residual masses after surgery. Data on the clinical and pathological response to NAC were collected and then statistically analyzed. PDL1 expression was detected in 24% of all studied cases, all of them were node-positive (P