Fig. 1: Visual presentation of the 2018 ASCO/CAP developed scoring system for breast cancer pertaining to IHC in SDC.

Score 0 (negative) shows no staining or incomplete/faint membrane staining in ≤10% of invasive tumor cells. Score 1+ (negative) shows incomplete/faint membrane staining in >10% of invasive tumor cells. Score 2+ (equivocal) shows weak/moderate complete membrane staining in >10% of invasive tumor cells. Score 3+ shows complete, intense membrane staining in >10% of invasive tumor cells. Abbreviations: IHC, immunohistochemistry.