Thyroid gland
Frozen section

Topic Completed: 1 March 2009

Minor changes: 14 March 2019

Copyright: 2003-2018,, Inc.

PubMed Search: frozen section thyroid

Shahid Islam, M.D., Ph.D.
Page views in 2019: 499
Page views in 2020 to date: 245
Cite this page: Islam S. Frozen section. website. Accessed August 6th, 2020.
Definition / general
  • Not indicated for most thyroid nodules due to low sensitivity; frequency has been decreasing (Virchows Arch 2008;453:433)
  • Results may conflict with FNA (Arch Otolaryngol Head Neck Surg 2007;133:874), but see Thyroid 2007;17:557
  • Well differentiated carcinomas often cannot be diagnosed on frozen section, regardless of experience of pathologist
  • Intraoperative cytology may be useful to detect nuclear features of papillary carcinoma (Mod Pathol 2000;13:210)

  • False negatives by frozen section:
    • Minimally invasive follicular carcinoma:

  • False positives by frozen section:
    • Metastatic papillary carcinoma: apparent metastases may actually be Riedel thyroiditis, diffuse hyperplasia of ectopic thyroid tissue or sequestered thyroid tissue
    • Freezing artifact may mimic nuclear features of papillary thyroid carcinoma or parathyroid neoplasms (43% of cases diagnosed as "suspicious for papillary carcinoma" are not papillary carcinoma at permanent section, Thyroid 2008;18:419)
    • Post FNA alterations can mimic capsular or vascular invasion
Microscopic (histologic) images

Images hosted on PathOut server:

Frozen section lacks nuclear features (left),
nuclear features present in permanent section (right)

Images hosted on other servers:

Follicular variant of papillary carcinoma:

Comparison of frozen section and permanent section

Additional references
Back to top