Therefore, we examined expression rates of the following antibody–drug conjugate targets using the tissue microarrays of anaplastic thyroid carcinomas: human epidermal growth factor receptor 2, nectin-4, trophoblast cell surface antigen 2, glycoprotein non-metastatic B, and B7-H3. The gene discussed is ERBB2; the disease is thyroid gland undifferentiated (anaplastic) carcinoma.