Thyroid gland
Miscellaneous nonneoplastic disorders
Calcification

Author: Andrey Bychkov, M.D., Ph.D. (see Authors page)

Revised: 2 November 2016, last major update February 2015

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed search: calcification [title] thyroid

Cite this page: Calcification. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/thyroidcalcification.html. Accessed December 9th, 2016.
Definition / General
  • Deposition of calcium salts in thyroid gland
  • More important to radiologists than pathologists
Epidemiology
  • Prevalence in thyroidectomy specimens is 15% (Head Neck 2002;24:651)
  • Found by ultrasound in 8% of benign (multinodular goiter) and 26% of malignant nodules (Head Neck 2002;24:651)
  • Increases with advancing age
Sites
  • Retrosternal thyroid / goiter tends to be calcified more heavily
Pathophysiology
  • Dystrophic calcification of thyroid results from degenerative changes (calcified colloid and degenerated epithelium, psammoma bodies, old hemorrhage, vessel wall, etc.)
  • Metastatic calcification is caused by elevated blood calcium / phosphate
  • Stromal calcification may progress to bone formation (Mod Pathol 2009;22:887)
Diagnosis
  • Core needle biopsy is superior to FNA for thyroid nodules with macrocalcification (Thyroid 2015;25:657)
Laboratory
  • Hypercalcemia due to hyperparathyroidism, in rare cases of metastatic calcification
Radiology Description
  • Microcalcifications (< 2 mm and without acoustic shadow by ultrasound) in thyroid nodules are usually psammoma bodies
  • Macrocalcifications (≥ 2 mm and with acoustic shadow) are secondary to tumor necrosis and can be seen in both benign and malignant nodules
  • Peripheral (eggshell) calcifications surrounding the nodule are secondary to chronic degenerative changes
  • Various patterns of calcification may be observed on Xray: nodular, flat, curvilinear, cloudy and a mixed type (Clin Radiol 1981;32:571)
Prognostic Factors
Case Reports
Clinical Images
Images hosted on other servers:

Thyroid nodule calcifications

Eggshell calcified retrosternal thyroid

Gross Images
Images hosted on other servers:

Muddy appearance

Micro Images
Images hosted on PathOut server:

Courtesy of Andrey Bychkov, M.D., Ph.D.

Abundant crystals of calcium oxalate

Calcium oxalate crystals



Images hosted on other servers:

Extensive dystrophic calcification

Osseous metaplasia with fatty marrow

Calcification induced artifact

Positive Stains
Differential Diagnosis