Radionuclide therapy is of special interest when there is “biological resistance” to EGFR- and/or HER2-targeted therapies probably because of intracellular signal pathway mutations1–4 and such resistance, or at least lack of therapy efficacy, has been reported for urinary bladder cancer.5–8 The receptors themselves, and not intracellular mutations and gene amplifications, are of main interest in these cases. The gene discussed is ERBB2; the disease is urinary bladder cancer.