The following histological and immunohistochemical parameters were analyzed: stroma type, tumor-infiltrating lymphocytes (TILs), eosinophils, neutrophils, central area of fibrosis, necrosis, and programmed cell death protein ligand 1 (PD-L1) expression in tumor and stromal cells.<h4>Results</h4>Low TILs percentage (≤50%) was associated with lower tumor grade (G2) (<i>p</i> = 0.013) and ER/PR positivity (<i>p</i> = 0.001). The gene discussed is ESR1; the disease is neoplasm.