ERBB2 and neoplasm: Patients with ERBB2-low expression demonstrated lower rates of pCR than those with ERBB2-zero expression (4675 [28.6%] vs 4787 [30.8%]; P < .001); ERBB2-low expression was associated with lower odds of pCR after adjustment for patient, socioeconomic, and tumor variables (odds ratio, 0.93; 95% CI, 0.88-0.99; P = .01).