Thyroid gland
Miscellaneous nonneoplastic disorders
Calcification

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

Revised: 10 February 2017, last major update February 2015

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed search: calcification thyroid

Cite this page: Calcification. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/thyroidcalcification.html. Accessed June 29th, 2017.
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:

Eggshell calcified retrosternal thyroid

Gross images

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Muddy appearance

Microscopic (histologic) images

Images hosted on PathOut server:

Contributed by Andrey Bychkov, M.D., Ph.D.:

Calcium oxalate
crystals (abundant)

Calcium oxalate crystals

Papillary thyroid carcinoma,
diffuse sclerosing variant


PTC follicular variant with ossification

Concentric layers of calcium deposition in tumor stroma

Psammoma bodies, laminated calcifications

Evolution in psammoma body in PTC

Psammoma bodies in benign appearing thyroid



Images hosted on other servers:

Extensive dystrophic calcification

Osseous metaplasia with fatty marrow

Calcification induced artifact

Positive stains
Differential diagnosis