This study aimed to investigate the association between TILs and Oncotype DX single gene scores for estrogen receptor (ER), progesterone receptor (PgR), and HER2 in HR+/HER2- breast cancer.<h4>Methods</h4>We retrospectively analyzed 260 patients with HR+/HER2- breast cancer who underwent surgery and Oncotype DX testing at Saitama Medical University International Medical Center between January 2022 and October 2024. This evidence concerns the gene HR and breast carcinoma.