ERBB2 and cancer: Patients in Cohort A and B underwent prior systemic treatments (one- or two-lines therapy), and here disitamab vedotin is administered alone, but the difference between these two groups is the HER2 expression: in Cohort A we can find HER2-positive cancer (IHC2+ or 3+ and FISH-positive) while in Cohort B only HER2-low (IHC 1+ or IHC 2+ and FISH-negative).