ERBB2 and medullary thyroid gland carcinoma: Regarding the characterization of the molecular subtype of MTC with metastasis, Luminal A was the most frequent subtype, observed in 8 cases (53.3%), followed by Luminal B HER-2 positive in 6 cases (33.3 percent) and Luminal B HER-2 negative in 1 case (6.6%).