Classification and General Considerations of Thyroid Cancer

Thyroid cancer is the most common malignancy in endocrine system, composed of four major types; papillary thyroid carcinoma, follicular thyroid carcinoma, anaplastic thyroid carcinoma, and medullary thyroid carcinoma. The incidence of thyroid cancer, especially differentiated thyroid cancer, is increasing in developed countries. Growing body of studies on molecular pathogenesis in thyroid cancer provide clues for further research and diagnostic/therapeutic targets. The general pathological classifications and clinical features of follicular cell derived thyroid carcinomas are overviewed, and recent advances of genetic alterations are discussed in this review.