• Like

Loading…

Flash Player 9 (or above) is needed to view presentations.
We have detected that you do not have it on your computer. To install it, go here.

Evaluation of Thyroid Nodules

  • 2,171 views
Uploaded on

 

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
2,171
On Slideshare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
119
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide
  • In most centers, the routine initial diagnostic evaluation of a solitary thyroid nodule no longer includes imaging studies. In the past, radionuclide scanning was an important imaging study performed routinely in the initial assessment of a thyroid nodule.
  • however, 5-8% of warm or cold nodules are malignant.
  • Figure 2. Scintigram of a Solitary Functioning Nodule in the Right Thyroid Lobe. Scintigraphy that was performed with the use of technetium-99m-labeled pertechnetate shows suppression of extranodular uptake in thyroid tissue. From:   Hegedus: N Engl J Med, Volume 351(17).October 21, 2004.1764-1771
  • Superimposition of abnormal nodular tissue and normally functional thyroid tissue can give impression of normally functioning tissue It is estimated that only half of malignant thyroid nodules present as cold defects
  • Figure 1. Sonogram of the neck in the transverse plane showing a normal right thyroid lobe and isthmus. L=small thyroid lobe in a patient who is taking suppressive amounts of L-thyroxine, I=isthmus, T=tracheal ring ( dense white arc is calcification, distal to it is artefact), C=carotid artery ( note the enhanced echoes deep to the fluid-filled blood vessel), J=jugular vein, S=Sternocleidomastoid muscle, m=strap muscle.
  • Figure 2. Sonogram of the left lobe of the thyroid gland in the transverse plane showing a rounded lobe of a goiter. L=enlarged lobe, I= widened isthmus, T=trachea, C=carotid artery ( note the enhanced echoes deep to the fluid-filled blood vessel), J=jugular vein, S=Sternocleidomastoid muscle, m=strap muscles, E=esophagus.
  • Usullally less than one cm. estimates up to 6 % of populatulation. Increase with age. One study said as many as 50% of women over 50 have them. Manage as a palpable nodule. If greater than 1.5 cm, do fnab. If less or benign, followup in 6 months. Figure 6. Sonograms of the right thyroid lobe in the longitudinal plane showing a 2.7 x 3.2 mm hypoechoic nodule that is delineated in the lower panel by the xx and ++ symbols. Note the linear hypoechoic structure below that (arrow). In the upper panel the bright structure is a Doppler signal and indicates a blood vessel below the nodule. The nodule is not vascular.
  • Unsatisfactory – 50% will be diagnostic on reaspiration.
  • Figure 9. Sonogram from an ultrasound guided fine needle aspiration biopsy showing a hypoechoic small nodule. The bright spot (above the arrows) is the tip of the needle within the nodule at the instant of aspiration. N=nodule.
  • Follicular Lymphocytes – hashimoto’s Colloid Subacute (granulomatous) thyroiditis – multinucleate giant cell.
  • Thick branching papillary tissue fragment with fibrovascular core in FNA Psammoma bodies Azurophilic granules containing calcitonin 4. pleomorphic nuclei and prominent nucleoli. Anaplastic

Transcript

  • 1. Evaluation of Thyroid Nodules Eric Oliver August 30, 2007
  • 2. Objectives
    • Discuss Common Causes of Thyroid Nodules
    • Highlight Application of Imaging Studies in Evaluation of the Thyroid Nodule
  • 3. The Thyroid Nodule
    • It is estimated that the prevalence of thyroid nodules in the general population is 4 - 7%.
    • Benign adenomas or cysts account for approximately 90% of detected thyroid nodules.
    • In the U.S., ~10,000 to 17,000 new cases of primary thyroid cancer are diagnosed each year.
    • 1,000 - 2,000 people die each year from primary thyroid carcinomas.
  • 4. Causes of Thyroid Nodularity
    • Benign
      • Follicular Adenomas
      • Multinodular goiter (colloid adenoma)
      • Hashimoto’s thyroiditis
      • Cysts (colloid, simple, hemorrhagic)
  • 5. Causes of Thyroid Nodularity
    • Malignant
      • Papillary Carcinoma
      • Follicular Carcinoma
      • Medullary Carcinoma
      • Anaplastic and poorly differentiated carcinoma
      • Primary lymphoma of the thyroid
      • Metastatic carcinoma (especially breast and renal cell carcinoma)
  • 6. Low Suspicion
    • Family history of autoimmune disease (eg, Hashimoto’s thyroiditis)
    • Family history of benign thyroid nodule or goiter
    • Presence of thyroid hormonal dysfunction
    • Pain or tenderness associated with nodule
    • Soft, smooth, and mobile nodule
  • 7.
    • Hegedus: N Engl J Med, Volume 351(17).October 21, 2004.1764-1771
  • 8. Case 1
    • A 16 year old female is seen because of a 6 month history of fatigue, nervousness, tremor, heat intolerance, polyphagia and weight loss. Her scholastic work has declined in quality. Recently she noticed some enlargement of her neck and prominence of her eyes. Physical examination reveals: B.P. 130/60 mm Hg., pulse 96/minute, smooth warm skin, eyelid retraction, symmetric thyroid enlargement, fine hand tremor and mild muscle weakness. Her TSH is low.
  • 9. Low TSH
    • Suspect independently functioning thyroid
    • ~10 percent of patients with a solitary nodule have a suppressed level of serum thyrotropin
    • Next Step: Scintography
  • 10. Radionuclide Scanning
    • Used to identify whether a nodule is functioning.
    • Functioning nodules are nearly always benign
    • Approximately 90 percent of nodules are nonfunctioning
    • 5 percent of nonfunctioning nodules are malignant
    • Thus, in the patient with a suppressed level of serum thyrotropin, radionuclide confirmation of a functioning nodule may obviate the need for biopsy.
  • 11. Scintigraphy
    • Usually either Technetium or Radioiodine
    • Normal follicular cells will trap both but only radioiodine is added to tyrosine and stored in the colloid space
    • Both benign and almost all malignant neoplastic tissue concentrate both radioisotopes less than normal thyroid tissue
    • 5-8% of warm or cold nodules are malignant
  • 12. Cold Nodules
    • Thyroiditis
    • Fibrosis
    • Cyst
    • Non-functioning Adenoma
    • Multinodular Goiter
    • Malignancy
  • 13. Scintigraphy
  • 14. Hot Nodules
    • Functioning Adenoma
    • Thyroiditis
    • Multinodular goiter
  • 15. Scintigraphy
  • 16. Limitations of Scintigraphy
    • Two dimensional scanning technique
    • Inability to measure the size of a nodule accurately
    • Missed malignant thyroid nodules
  • 17. Case 2
    • TR is a 40 year old female who presents for her annual physical. On exam, you palpate a 1.5x 2 cm nodule in the right lobe of her thyroid gland. The nodule is non-tender and mobile. Both her TSH and free T4 are normal.
    • What test would you order next?
  • 18. Ultrasonography
    • Facilitate fine needle aspiration biopsy of a nodule
    • Assess the comparative size of nodules, lymph nodes, or goiters in patients who are under observation or therapy
    • Evaluate for recurrence of a thyroid mass after surgery
  • 19. Normal Right Thyroid Lobe
  • 20. Goiter
  • 21. Incidentalomas
  • 22. Fine-Needle Aspiration Biopsy
    • Most important step in the diagnostic evaluation of thyroid nodules, exception would include hyperthyroidism where scintigraphy should be performed first or highly suspicious exams warranting immediate surgery.
    • Mean sensitivity higher than 80% and specificity higher than 90%.
    • Can categorize tissue into the following diagnostic categories: malignant, benign, thyroiditis, follicular neoplasm, suspicious, or nondiagnostic
    • Cost Effective – some studies estimate that it reduces cost by 25 % and reduce the need for diagnostic thyroidectomy by 20-50%.
  • 23. FNAB Limitations
    • Hypocellular aspirates may be observed in cystic nodules, or they may be related to biopsy technique.
    • The absence of malignant cells in an acellular or hypocellular specimen does not exclude malignancy.
    • Inability to reliably distinguish a benign follicular neoplasm from a malignant neoplasm.
    • Aspirates may be required from multiple sites of the nodule to improve sampling.
  • 24. FNAB
  • 25. Ultrasound Guided FNAB
  • 26. FNAB
  • 27. FNAB
  • 28. Case 3
    • F.H. is a 66 year old man who complains of a “a bump in his throat.” He states that he has also developed some discomfort while eating more recently. PMH is significant for childhood neck irradiation. There is no palpable mass on exam and oropharynx is clear.
  • 29. Algorithm for the Cost-Effective Evaluation and Treatment of a Clinically Detectable Solitary Thyroid Nodule Hegedus: N Engl J Med, Volume 351(17). October 21, 2004. 1764-1771
  • 30. Take Home Points
    • Hyperfunctioning nodules (Low TSH, High T3/T4) are almost always benign and biopsy is generally not recommended. Scintigraphy may aid in evaluation and treatment.
    • Consider FNAB for patients with normal and hypofunctioning nodules.
    • Patients in which there is a high suspicion can immediately be referred to ENT for surgery.
  • 31. References
    • http://www.thyroidmanager.org/FunctionTests/ultra-frame.htm
    • Ford. Evaluation of Thyroid Nodules. http://ctm.stanford.edu/06-07/Thyroid%20Nodule_Ford_6_18_07.pdf
    • Hegedus: N Engl J Med, Volume 351(17).October 21, 2004.1764-1771
    • Miller. Management of Thyroid Nodules. Radiology Rounds. MGH Department of Radiology. 2005. http://www.massgeneralimaging.org/newsletter/march_2005
    • Nguyen GK. Fine-needle aspiration of the thyroid: an overview. CytoJournal 2005, 2: 12 http://bmc.ub.uni-potsdam.de/1742-6413-2-12/
    • Ross. Evaluation of the Thyroid Nodule. J Nucl Med 1991; 32:2181-2192.
    • Society of Nuclear Medicine Procedure Guideline for Thyroid Scintigraphy. 1999. http://interactive.snm.org/docs/pg_ch05_0403.pdf