When assessed in the context of residual disease, high-level expression of ROR1 associated with a significantly worse outcome for patients with HR + HER2- tumors who had a high post-treatment residual cancer burden (RCB-II/III) (HR = 1.41, 95% CI = 1.11–1.80, LRp = 0.01). The gene discussed is ERBB2; the disease is cancer.