ESR1 and breast cancer: In our study, clinical pathological tumor types, age, tumor location, histological grade, lymph node metastasis, and molecular phenotype expression (ER, PR, HER-2, Ki-67, CK5/6, E-cad, P63, and P120) for breast cancer patients were compared across the subgroups to discuss in detail the molecular phenotypes and clinical characteristics of CHBC compared to other types of breast cancer.