UNUSUAL TYPES OF THYROID NEOPLASMS

Although relatively rare, several important varieties or subtypes of t hyroid cancer deserve clinical attention. The tall cell variant of pap illary thyroid cancer, insular thyroid cancer, squamous cell carcinoma of the thyroid, anaplastic thyroid carcinoma, and primary thyroid lym phoma are discussed. Each of these entities has clinical and histologi c characteristics that should be recognized to provide appropriate cli nical treatment. Ln addition, Cowden's syndome and familial adenomatou s polyposis are reviewed, emphasizing their relationship to the diagno sis and presentation of thyroid cancer.