INSM1 and medullary thyroid gland carcinoma: In the head and neck area, sinonasal neuroendocrine carcinoma, neuroendocrine carcinomas localized in the hypopharynx, larynx, trachea and parapharyngeal space, as well as HPV-related neuroendocrine carcinomas, paraganglioma, and medullary thyroid carcinoma were shown to be immunoreactive for INSM1.