[Anaplastic, insular, and medullary carcinoma of the thyroid]

Anaplastic carcinoma, insular carcinoma and medullary carcinoma (both familiar and sporadic forms) represent the 7-25% of all thyroid tumors. Anaplastic carcinoma is one of most aggressive human tumors and the therapeutic options proposed have failed to improve the prognosis of these patients. Insular carcinoma is a not well known thyroid neoplasia described for the first time in 1984 and showing intermediate biological behaviour between differentiated and anaplastic forms. Medullary carcinoma arises from parafollicular"C" cells of the gland and then may be considered a neuroendocrine tumor. Choice therapy is surgery, tiroxine is only substitutive, familiar screening is mandatory. Chemotherapy (dacarbazine or cisplatin and doxorubicine), radiotherapy and recently octreotide anologues, may be useful for relapsing not operable forms.