Adenosquamous carcinoma of the thyroid gland.

A case of adenosquamous carcinoma of the thyroid gland is presented. This rare form of cancer behaves in an aggressive manner similar to anaplastic carcinoma and is characterized histologically by the intimate blending of the squamous and glandular elements. The prognostic significance of identifying areas of malignant squamous epithelium within papillary carcinoma as opposed to the much more common benign squamous metaplasia, is highlighted. The pathogenesis, differential diagnosis and management of the condition are discussed.