ERBB2 and neoplasm: Similarly, T1a patients of the matched cohort (Tables 5 and 6) with tumor grades I (P = 0.27), II (P = 0.99), and III (P = 0.57) and molecular subtypes HoR + /HER2- (P = 0.66), HoR + /HER2 + (P = 0.20), HoR/HER2 + (P = 0.27), and HoR-/HER2- (P = 0.48) did not obtain OS benefit from adjuvant chemotherapy.