Thyroid Cancer

  • Diagnosis
  • Algorithms
  • Screening
  • Monitoring
  • Background
  • Lab Tests
  • References
  • Related Topics
  • Videos

Indications for Testing

Thyroid nodule, abnormal cervical nodes, abnormal imaging

Laboratory Testing

  • Refer to Thyroid Nodules Testing algorithm for information regarding which nodules require additional follow-up (based on 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer)
  • Initial laboratory testing
    • Thyroid-stimulating hormone (TSH)
      • Low or suppressed TSH – order free T4
        • Elevated free T4 -- proceed to thyroid radioisotope study after thyroid ultrasound
        • Normal or elevated TSH – consider thyroid ultrasound and fine needle aspiration (FNA) biopsy
  • FNA – used to obtain tissue for definitive diagnosis of suspicious thyroid nodules and determination of need for surgery
    • Need for biopsy is determined by size and characteristics of nodule on ultrasound
    • Biopsy may be obviated in the presence of compressive symptoms with immediate referral for surgical resection
  • Tumor markers – for medullary thyroid cancer (MTC), calcitonin concentrations are directly related to C-cell mass

Imaging Studies

  • Ultrasound – initial evaluation for thyroid nodules to aid in determining
    • Nodule size
    • Solid or cystic nature of nodule(s)
    • Number of nodules present
  • FNA biopsy
    • Procedure of choice for evaluating suspicious thyroid nodules
    • Ideally, performed with ultrasound guidance
    • If FNA biopsy nondiagnostic – repeat with new specimen

Surgical Pathology

  • Molecular testing
    • Thyroid nodules discovered by palpation or imaging are most often evaluated by FNA biopsy for diagnosis by cytopathologist
    • Only ~10% of nodules are malignant, but >90% carry certain gene mutations
    • Molecular markers are useful in
      • Establishing diagnosis of malignancy in “indeterminate” or “atypical” cytologic evaluations in order to prevent excessive surgery in patients who have benign pathology
      • Follicular or Hürthle cell histology types (National Comprehensive Cancer Network [NCCN], 2016; ATA, 2012)
      • Targeted therapeutic decision making (NCCN, 2016)
    • Detection of vascular endothelial growth factors (VEGF) in MTC may be helpful in targeted therapy with vandetanib  (Wells, 2012)
    • Other potential molecular markers for immunotherapy
      • Thyroid – VEGFR, FGFR, RET, KIT, PDGFR
  • Histology
    • Most diagnosis is possible using cytomorphology (on FNA specimens) or histomorphology (on surgical resection specimens)
    • Occasionally, immunohistochemical stains may be used to support diagnosis
      • Thyroglobulin, thyroid transcription factor 1 (TTF-1), and PAX8 are supportive of thyroid origin
      • Parathyroid hormone (PTH) immunostain may be used to exclude parathyroid origin
    • MTC
      • Calcitonin may be evaluated by immunostain and/or by serologic evaluation

Germline Genetic Testing for Familial Cancer Syndromes

  • Evidence is insufficient to support a recommendation for genetic testing; however, the following general guidelines have been suggested
    • Positive family history of thyroid cancer – consider MEN/PTEN testing
    • Consider testing in the following (American College of Medical Genetics and Genomics [ACMG], 2015)
      • MTC
      • Non-MTC with 1 additional Carney complex criterion
      • Non-MTC with 2 additional Cowden syndrome criteria
      • Papillary thyroid cancer (cribriform-morular variant)

Differential Diagnosis

  • U.S. Preventive Services Task Force (USPSTF) recommends against screening for thyroid cancer in the general population (neck palpitation or ultrasound) (USPSTF, 2017)
    • USPSTF guideline does not address screening in those with
      • Higher risk for thyroid cancer
      • History of radiation exposure to the head/neck
      • Exposure to radiation fallout
      • Family history in first-degree relative
      • Risk of genetic predisposition
  • Screening does not result in decreased mortality (National Cancer Institute, 2017)
  • National Comprehensive Cancer Network (NCCN) (2016) and American Thyroid Association (ATA) (2015) recommendations
    • Papillary and follicular thyroid cancer – physical examination, thyroid stimulating hormone (TSH), thyroglobulin, and antithyroglobulin antibodies at 6 and 12 months, as well as whole-body imaging with radioiodine (I-131)
      • Only useful in patients with thyroidectomy and remnant ablation
      • Annually thereafter if scan evaluations are normal
      • Thyroglobulin should be measured after TSH stimulation and withdrawal of thyroid hormone replacement
      • All specimens should be processed in same lab
      • If presence of thyroglobulin antibodies detected, use tandem mass spectometry measurements to mediate antibody interference
    • Medullary thyroid carcinoma (MTC) – sequential calcitonin levels and carcinoembryonic antigen (CEA) levels
      • In patients with advanced MTC, marked elevation in serum CEA level that is out of proportion to a lower serum calcitonin level, or normal or low levels of both serum calcitonin and CEA, indicates poorly differentiated MTC
    • Benign nodules not meeting criteria for fine needle aspiration (FNA)
      • Repeat ultrasound at 6 to 12 months
      • If stable after 1-2 years, consider 3- to 5-year monitoring by ultrasound

Thyroid cancer is the most common endocrine malignancy, although the lifetime risk of developing thyroid cancer is low.


  • Incidence – ~13.5/100,000
    • Incidence increased >3-fold from 1950-2004, but no difference in mortality rate during same time frame
    • >62,000 new cases of thyroid carcinoma diagnosed in U.S. in 2013 (National Comprehensive Cancer Network [NCCN], 2016)
  • Age – incidence increases with age
    • Peaks in 40s
  • Sex – M<F, 1:2
    • Fifth most common malignancy in women
    • Male sex associated with worse prognosis
  • Ethnicity – more common in Caucasian North Americans than in African Americans


  • Three main histologic types (NCCN, 2016)
    • Differentiated – papillary (80%), follicular (~10%), Hürthle cell (3%)
    • Medullary thyroid cancer (MTC) (4%)
    • Anaplastic – aggressive undifferentiated carcinoma (2%)
      • Almost uniformly fatal

Risk Factors

  • Exposure to ionizing radiation
  • Genetic mutations – PTEN, MEN, RET
  • Familial syndromes
    • Syndromic with predominance of nonthyroidal tumors (predominantly autosomal dominant inheritance)
    • Nonsyndromic or familial with preponderance of nonmedullary thyroid carcinoma
      • Familial papillary thyroid carcinoma (PTC)
      • Familial PTC associated with renal neoplasia
      • Familial multinodular goiter
      • Familial nonmedullary thyroid carcinoma type 1
  • Family history of thyroid cancer


  • Classification based on tumor cell type

    Clinical Presentation

    • Usually presents as thyroid nodule on clinical examination or incidentally on imaging
      • Most thyroid nodules are benign
    • Enlarged thyroid
    • Hoarseness or enlarged cervical adenopathy (suggests metastatic disease)
    Tests generally appear in the order most useful for common clinical situations. Click on number for test-specific information in the ARUP Laboratory Test Directory.

    Thyroid Stimulating Hormone with reflex to Free Thyroxine 2006108
    Method: Quantitative Electrochemiluminescent Immunoassay

    Thyroglobulin, Serum or Plasma with Reflex to LC-MS/MS or CIA 2006685
    Method: Quantitative Chemiluminescent Immunoassay/High Performance Chromatography-Tandem Mass


    Limit of detection with LC-MS/MS – 0.5 ng/mL

    Results obtained with different test methods or kits cannot be used interchangeably

    Thyroglobulin results, regardless of concentration, should not be interpreted as absolute evidence for presence or absence of papillary or follicular thyroid cancer

    Not recommended for use as a screening procedure to detect presence of thyroid cancer in general population

    Thyroglobulin by LC-MS/MS, Serum or Plasma 2006550
    Method: High Performance Liquid Chromatography-Tandem Mass Spectrometry


    Lower limit of detection with LC-MS/MS – 0.5 ng/mL

    Calcitonin 0070006
    Method: Quantitative Chemiluminescent Immunoassay


    Results obtained with different assay methods or kits cannot be used interchangeably

    Results, regardless of level, should not be interpreted as absolute evidence of the presence or absence of malignant disease

    Thyroglobulin, Fine Needle Aspiration (FNA) 0020753
    Method: Quantitative Chemiluminescent Immunoassay

    Multiple Endocrine Neoplasia Type 2 (MEN2), RET Gene Mutations by Sequencing 0051390
    Method: Polymerase Chain Reaction/Sequencing


    Does not evaluate regulatory region mutations, deep intronic mutations, large deletions/duplications, RET exons other than 5, 8, 10, 11, 13-16

    Diagnostic errors can occur due to rare sequence variations

    Calcitonin by Immunohistochemistry 2003481
    Method: Immunohistochemistry

    Parathyroid Hormone (PTH) by Immunohistochemistry 2004118
    Method: Immunohistochemistry

    PAX8 by Immunohistochemistry 2010787
    Method: Immunohistochemistry

    Thyroglobulin by Immunohistochemistry 2004145
    Method: Immunohistochemistry

    Thyroid Transcription Factor (TTF-1) by Immunohistochemistry 2004166
    Method: Immunohistochemistry

    BRAF Codon 600 Mutation Detection by Pyrosequencing 2002498
    Method: Polymerase Chain Reaction/Pyrosequencing


    Oncogenic mutations other than codon 600 will not be detected

    BRAF V600E Mutation Detection in Circulating Cell-Free DNA by Digital Droplet PCR 2013921
    Method: Polymerase Chain Reaction

    KRAS Mutation Detection 0040248
    Method: Polymerase Chain Reaction/Pyrosequencing


    Oncogenic mutations other than codons 12, 13, and 61 will not be detected

    NRAS Mutation Detection by Pyrosequencing 2003123
    Method: Polymerase Chain Reaction/Pyrosequencing


    Oncogenic mutations other than codons 12, 13, and 61 will not be detected

    RET Gene Rearrangements by FISH 2012654
    Method: Fluorescence in situ Hybridization


    Does not identify translocation partner or variant

    Solid Tumor Mutation Panel by Next Generation Sequencing 2007991
    Method: Massively Parallel Sequencing


    Not intended to detect minimal residual disease


    American Thyroid Association Guidelines Task Force, Kloos RT, Eng C, Evans DB, Francis GL, Gagel RF, Gharib H, Moley JF, Pacini F, Ringel MD, Schlumberger M, Wells SA. Medullary thyroid cancer: management guidelines of the American Thyroid Association. Thyroid. 2009; 19(6): 565-612. PubMed

    Cobin RH, Gharib H, Bergman DA, Clark OH, Cooper DS, Daniels GH, Dickey RA, Duick DS, Garber JR, Hay ID, Kukora JS, Lando HM, Schorr AB, Zeiger MA, Thyroid Carcinoma Task Force. AACE/AAES medical/surgical guidelines for clinical practice: management of thyroid carcinoma. American Association of Clinical Endocrinologists. American College of Endocrinology. Endocr Pract. 2001; 7(3): 202-20. PubMed

    Hampel H, Bennett RL, Buchanan A, Pearlman R, Wiesner GL, Guideline Development Group, American College of Medical Genetics and Genomics Professional Practice and Guidelines Committee and National Society of Genetic Counselors Practice Guidelines Committee. A practice guideline from the American College of Medical Genetics and Genomics and the National Society of Genetic Counselors: referral indications for cancer predisposition assessment. Genet Med. 2015; 17(1): 70-87. PubMed

    Haugen BR, Alexander EK, Bible KC, Doherty G, Mandel SJ, Nikiforov YE, Pacini F, Randolph G, Sawka A, Schlumberger M, Schuff KG, Sherman SI, Sosa JA, Steward D, Tuttle M, Wartofsky L. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid. 2016; 26(1): 1-133. PubMed

    National Guideline Clearinghouse (NGC). Guideline summary: Final recommendation statement: thyroid cancer: screening. In: National Guideline Clearinghouse (NGC) [Web site]. Rockville (MD): Agency for Healthcare Research and Quality (AHRQ); 2017 May 01. [cited 2017 Sep 25].

    NCCN Clinical Practice Guidelines in Oncology, Thyroid Carcinoma. National Comprehensive Cancer Network. Fort Washington, PA [Accessed: Feb 2017]

    Pacini F, Castagna MG, Brilli L, Pentheroudakis G, ESMO Guidelines Working Group. Thyroid cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2012; 23 Suppl 7: vii110-9. PubMed

    Protocol for the Examination of Specimens from Patients with Carcinomas of the Thyroid Gland. Based on AJCC/UICC TNM, 7th ed. Protocol web posting date: Jan 2016. College of American Pathologists (CAP). Northfield, IL [Revised Jan 2016; Accessed: Jun 2017]

    Smallridge RC, Ain KB, Asa SL, Bible KC, Brierley JD, Burman KD, Kebebew E, Lee NY, Nikiforov YE, Rosenthal S, Shah MH, Shaha AR, Tuttle M, American Thyroid Association Anaplastic Thyroid Cancer Guidelines Taskforce. American Thyroid Association guidelines for management of patients with anaplastic thyroid cancer. Thyroid. 2012; 22(11): 1104-39. PubMed

    Thyroid Cancer Screening (PDQ)–Health Professional Version. National Cancer Institute. [Updated Aug 2017; Accessed: Sep 2017]

    Wells SA, Asa SL, Dralle H, Elisei R, Evans DB, Gagel RF, Lee N, Machens A, Moley JF, Pacini F, Raue F, Frank-Raue K, Robinson B, Rosenthal S, Santoro M, Schlumberger M, Shah M, Waguespack SG, American Thyroid Association Guidelines Task Force on Medullary Thyroid Carcinoma. Revised American Thyroid Association guidelines for the management of medullary thyroid carcinoma. Thyroid. 2015; 25(6): 567-610. PubMed

    General References

    Bhaijee F, Nikiforov YE. Molecular analysis of thyroid tumors. Endocr Pathol. 2011; 22(3): 126-33. PubMed

    Boufraqech M, Patel D, Xiong Y, Kebebew E. Diagnosis of thyroid cancer: state of art. Expert Opin Med Diagn. 2013; 7(4): 331-42. PubMed

    Cabanillas ME, Dadu R, Hu MI, Lu C, Gunn GB, Grubbs EG, Lai SY, Williams MD. Thyroid gland malignancies. Hematol Oncol Clin North Am. 2015; 29(6): 1123-43. PubMed

    Fischer S, Asa SL. Application of immunohistochemistry to thyroid neoplasms. Arch Pathol Lab Med. 2008; 132(3): 359-72. PubMed

    Hadoux J, Pacini F, Tuttle M, Schlumberger M. Management of advanced medullary thyroid cancer. Lancet Diabetes Endocrinol. 2016; 4(1): 64-71. PubMed

    Howell GM, Hodak SP, Yip L. RAS mutations in thyroid cancer. Oncologist. 2013; 18(8): 926-32. PubMed

    Kang G, Cho EY, Shin JH, Chung J, Kim JW, Oh YL. Role of BRAFV600E mutation analysis and second cytologic review of fine-needle aspiration for evaluating thyroid nodule. Cancer Cytopathol. 2012; 120(1): 44-51. PubMed

    Keutgen XM, Filicori F, Fahey TJ. Molecular diagnosis for indeterminate thyroid nodules on fine needle aspiration: advances and limitations. Expert Rev Mol Diagn. 2013; 13(6): 613-23. PubMed

    Nikiforov YE. Molecular diagnostics of thyroid tumors. Arch Pathol Lab Med. 2011; 135(5): 569-77. PubMed

    Nosé V. Familial thyroid cancer: a review. Mod Pathol. 2011; 24 Suppl 2: S19-33. PubMed

    Omur O, Baran Y. An update on molecular biology of thyroid cancers. Crit Rev Oncol Hematol. 2014; 90(3): 233-52. PubMed

    Popoveniuc G, Jonklaas J. Thyroid nodules. Med Clin North Am. 2012; 96(2): 329-49. PubMed

    Pusztaszeri MP, Bongiovanni M, Faquin WC. Update on the cytologic and molecular features of medullary thyroid carcinoma. Adv Anat Pathol. 2014; 21(1): 26-35. PubMed

    Soares P, Celestino R, Melo M, Fonseca E, Sobrinho-Simões M. Prognostic biomarkers in thyroid cancer. Virchows Arch. 2014; 464(3): 333-46. PubMed

    Spencer C, Fatemi S. Thyroglobulin antibody (TgAb) methods - Strengths, pitfalls and clinical utility for monitoring TgAb-positive patients with differentiated thyroid cancer. Best Pract Res Clin Endocrinol Metab. 2013; 27(5): 701-12. PubMed

    Tavares C, Melo M, Cameselle-Teijeiro JM, Soares P, Sobrinho-Simões M. Endocrine tumours: Genetic predictors of thyroid cancer outcome. Eur J Endocrinol. 2016; 174(4): R117-26. PubMed

    Theoharis C, Roman S, Sosa JA. The molecular diagnosis and management of thyroid neoplasms. Curr Opin Oncol. 2012; 24(1): 35-41. PubMed

    Wells SA, Robinson BG, Gagel RF, Dralle H, Fagin JA, Santoro M, Baudin E, Elisei R, Jarzab B, Vasselli JR, Read J, Langmuir P, Ryan AJ, Schlumberger MJ. Vandetanib in patients with locally advanced or metastatic medullary thyroid cancer: a randomized, double-blind phase III trial. J Clin Oncol. 2012; 30(2): 134-41. PubMed

    References from the ARUP Institute for Clinical and Experimental Pathology®

    Bentz BG, Miller BT, Holden JA, Rowe LR, Bentz JS. B-RAF V600E mutational analysis of fine needle aspirates correlates with diagnosis of thyroid nodules. Otolaryngol Head Neck Surg. 2009; 140(5): 709-14. PubMed

    Fnais N, Soobiah C, Al-Qahtani K, Hamid JS, Perrier L, Straus SE, Tricco AC. Diagnostic value of fine needle aspiration BRAF(V600E) mutation analysis in papillary thyroid cancer: a systematic review and meta-analysis. Hum Pathol. 2015; 46(10): 1443-54. PubMed

    Givens DJ, Buchmann LO, Agarwal AM, Grimmer JF, Hunt JP. BRAF V600E does not predict aggressive features of pediatric papillary thyroid carcinoma. Laryngoscope. 2014; 124(9): E389-93. PubMed

    Kushnir MM, Rockwood AL, Roberts WL, Abraham D, Hoofnagle AN, Meikle W. Measurement of thyroglobulin by liquid chromatography-tandem mass spectrometry in serum and plasma in the presence of antithyroglobulin autoantibodies. Clin Chem. 2013; 59(6): 982-90. PubMed

    Layfield LJ, Cibas ES, Gharib H, Mandel SJ. Thyroid aspiration cytology: current status. CA Cancer J Clin. 2009; 59(2): 99-110. PubMed

    Layfield LJ, Morton MJ, Cramer HM, Hirschowitz S. Implications of the proposed thyroid fine-needle aspiration category of "follicular lesion of undetermined significance": A five-year multi-institutional analysis. Diagn Cytopathol. 2009; 37(10): 710-4. PubMed

    Li QK, Nugent SL, Straseski J, Cooper D, Riedel S, Askin FB, Sokoll LJ. Thyroglobulin measurements in fine-needle aspiration cytology of lymph nodes for the detection of metastatic papillary thyroid carcinoma. Cancer Cytopathol. 2013; 121(8): 440-8. PubMed

    Margraf RL, Calderon FR, Mao R, Wittwer CT. RET mutation scanning update: exon 15. Clin Chem. 2009; 55(11): 2059-61. PubMed

    Oakley GM, Curtin K, Layfield L, Jarboe E, Buchmann LO, Hunt JP. Increased melanoma risk in individuals with papillary thyroid carcinoma. JAMA Otolaryngol Head Neck Surg. 2014; 140(5): 423-7. PubMed

    Rowe LR, Bentz BG, Bentz JS. Utility of BRAF V600E mutation detection in cytologically indeterminate thyroid nodules. Cytojournal. 2006; 3: 10. PubMed

    Szankasi P, Reading S, Vaughn CP, Prchal JT, Bahler DW, Kelley TW. A quantitative allele-specific PCR test for the BRAF V600E mutation using a single heterozygous control plasmid for quantitation: a model for qPCR testing without standard curves. J Mol Diagn. 2013; 15(2): 248-54. PubMed

    Medical Reviewers

    Content Reviewed: 
    March 2017

    Last Update: September 2017