Adenosquamous carcinoma of the thyroid: a case report and review of the literature.

A case of mixed squamous cell carcinoma and papillary adenocarcinoma of the thyroid in a 75-year-old woman is described. Review of 19 reported adenosquamous carcinoma including the present case revealed that they tended to occur in the sixth and seventh decades of life with an average age of 63.84 years and without sexual predilection. Local invasion and metastases of this highly fatal neoplasm are common.