Most patients were older than or equal to 50 years old (68.6%), were White people (74.4%) and in stage II (73.3%), had undergone mastectomy (64.9%), had received radiation therapy (53.1%) and chemotherapy (75.5%), and the most common breast cancer subtype was HR+/HER2− (luminal A) (39.2%). This evidence concerns the gene HR and breast cancer.