ERBB2 and invasive breast carcinoma: Notwithstanding the fact that another retrospective study involving a total of only 141 patients pointed out that the probability of omitting SLNB increased with age in 70 years or older patients with ER-positive, HER2-negative, and clinical T1N0 invasive breast cancer (14), few studies have accurately pointed out a specific population that would be exempt from SLNB.