Akashi M, Yamaguchi R, Kusano H, et al. - A total of 166 individuals with HER2+ invasive breast carcinoma (BC) were categorized into luminal B (LH) (n = 110; [66.3%]) and non-luminal type (NLH) groups (n = 56; [33.7%]) in order to examine the clinicohistomorphological characteristics of each HER2+ BC subgroup. The morphological investigation exhibited that NLH incorporated a percentage of patients with comedo necrosis, while LH patients owned significantly more central scarring. NLH presented significantly greater rates of tumor-infiltrating lymphocytes (TILs) and healing in terms of immune responsiveness. The LH-high and NLH groups explicated different features and the LH-low group seemed to illustrate intermediate features according to multinomial analyses using covariates highlight tumor morphology and immune response outcomes. Therefore, these results strengthen the classification of HER2+ BC into two principal subgroups, LH-high, and NLH, on the basis of the tumor morphology and immune response and LH-high proliferates through scirrhous and/or spiculated growth with a central scar, while the primary proliferation pattern of NLH is on the basis of in situ carcinomas comprising comedo necrosis with obvious TILs and healing.