ERBB2 and breast cancer: In additional sensitivity analyses which excluded patients with HER2-positive breast cancer, similar associations between the luminal-like subtype and all endpoints were observed in both the total follow-up period and specific follow-up periods (years 0-5 versus years 5-15) (Supplementary Table S2, available at https://doi.org/10.1016/j.esmoop.2025.104154).