Prognostic value of programmed death ligand-1 expression in breast carcinomas

Abstract

ObjectivesTo assess the prognostic value of programmed death ligand-1 (PDL-1) expression in patients with nonmetastatic breast carcinoma patients both in tumor cells and tumor-infiltrating lymphocytes (TILs).BackgroundPDL-1 has emerged as important immune biomarkers in breast cancer. It can be targeted with immunotherapy, which represents a significant advancement in the management of this disease.Patients and methodsParaffin blocks of patients with breast cancer will be tested for the expression of PDL-1 both on TILs and malignant epithelial cells and correlated with patients and disease features.ResultsThis retrospective study included 60 patients. PDL-1 expression was positive in 33 (55%) patients on TILs and was positive in tumor cells in 27 (45%) patients of the studied patients. There was no significant relation between PDL-1 expression on TILs and patients and disease features. There was significant relation between positive PDL-1 expression on epithelial cells and triple-negative breast cancer, estrogen receptor negative, progesterone receptor negative status (P = 0.006, 0.006, and 0.006). PDL-1 intensity in intratumoral lymphocytes is significantly related to tumor stage (P = 0.006). PDL-1 H score in malignant epithelial cells was significantly related to disease stage (P = 0.021). Tumor size, HER-2neu status, and PDL-1 H score on malignant epithelial cells were independent risk factors for disease progression.ConclusionPDL-1 expression is common in both malignant tumor cells and TILs. A higher PDL-1 H score on malignant epithelial cells was associated with longer time to progression.