However, their significance in HR+/HER2- BC is unknown.68 Luminal BC is the least immunogenic subtype of all BCs.69 High TIL abundance is associated with relatively better distance disease-free survival (DDFS)69 and prognosis.70 However, the role of TILs in HR+/HER2- BC remains unknown and might be elucidated through future prospective cohort studies. This evidence concerns the gene ERBB2 and breast cancer.