Nonmedullary thyroid cancer (NMTC) comprises thyroid cancers of follicular cell origin and accounts for more than 95% of all thyroid cancer cases. The remaining cancers originate from parafollicular cells (medullary thyroid cancer, MTC; 155240). NMTC is classified into 4 groups: papillary, follicular, Hurthle cell (607464), and anaplastic. Approximately 5% of NMTC is hereditary, occurring as a minor component of a familial cancer syndrome (e.g., familial adenomatous polyposis 175100, Carney complex 160980) or as a primary feature (familial NMTC or FNMTC). Papillary thyroid cancer (PTC) is the most common histologic subtype of FNMTC, accounting for approximately 85% of cases (summary by Vriens et al., 2009).
For a general phenotypic description and a discussion of genetic heterogeneity of NMTC, see NMTC1 (188550). [from
OMIM]