CK19

See also : KRT19

Diagnostic use :

 In Thyroid:

• confirm diagnosis of papillary thyroid carcinoma in cytology or equivocal cases (Arch Pathol Lab Med 2003;127:579, Mod Pathol 2006;19:1631);
• help distinguish follicular variant of papillary thyroid carcinoma (CK19+) from :
  • (a) follicular adenoma (CK19-, Endocr Pathol 2006;17:213, Am J Clin Pathol 2006;126:700 but see Am J Clin Pathol 2001;116:696),
  • (b) hyalinizing trabecular adenoma (CK19-, Am J Surg Pathol 2006;30:1269),
  • (c) Grave’s disease (weak / negative CK19, Endocr Pathol 2005;16:63),
  • (d) multinodular goiter with papillary areas (Endocr Pathol 2002;13:207);
  • note that CK19 may stain benign thyroid lesions.