Risk stratification and approach to solitary thyroid nodule

1. Approach to Solitary Thyroid Nodule
Karthik Balachandran
2/2/2019

2. Agenda
Introduction
Epidemiology
Guiding Values
Evaluation
Clinical
Lab
Imaging
Cytology
Management
Benign
Indeterminate
Summary
Case
Case 1
Conclusions
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3. Introduction
Definition
Thyroid Nodule a discrete lesion in the thyroid gland that is radiologically distinct
from the surrounding thyroid parenchyma
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4. Introduction Epidemiology
Epidemiology
• Prevalence depends on
Age -increasing age - increasing prevalence
Mode of detection
Autopsy > USG > CT > FDG PET ==Palpation
Iodine status of the population
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5. Introduction Epidemiology
Epidemiology
65 % on USG studies!
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6. Introduction Guiding Values
Principle of management
• Conservation of thyroid vs conservation of life
• Approach to uncertainty
• Availability of resources
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7. Introduction Guiding Values
Principle of management
• Conservation of thyroid vs conservation of life
• Approach to uncertainty
• Availability of resources
Risk Stratification
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8. Introduction Guiding Values
Risk Stratification
History Exami-
nation
Labs Scan FNAC
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9. Evaluation Clinical
History
• Most patients are asymptomatic
• Globus sensation - more common if size > 3cm and position close to trachea (
isthmic nodules > para isthmic nodules)
• Dysphagia - extrinsic compression of cervical esophagus more common in
posteriorly located nodule in left lobe1
• Pain - bleeding into the nodule
• Dysphonia, dyspnea
1
C Durante et al. “The Diagnosis and Management of Thyroid Nodules: A Review.”. In: JAMA
319.9 (2018), pp. 914–924.
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10. Evaluation Clinical
History
Risk factors for thyroid cancer
• Previous head and neck irradiation
• Exposure to nuclear fallout e.g. from Chernobyl
• Family history of medullary thyroid carcinoma or multiple endocrine
neoplasia type 2
• Family history of papillary thyroid carcinoma, familial PolyposisColi,
Cowden’s or Gardner’s Syndrome
• Age less than 20 years or greater than 70 years
• Recent onset of hoarseness, dysphonia, dysphagia or dyspnoea
• Past medical history of thyroid cancer
• Male sex
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11. Evaluation Clinical
Examination2
Causes of anterior neck masses
• Congenital conditions (lateral neck: brachial anomalies, cystic hygroma;
central neck: thyroglossal duct cysts)
• Inflammatory/infectious diseases (lymphadenopathy, sialadenitis, neck
abscess, tuberculosis, cat-scratch disease [Bartonella lymphadenitis])
• Trauma
• Thyroid nodule
• Malignancy
2
C Durante et al. “The Diagnosis and Management of Thyroid Nodules: A Review.”. In: JAMA
319.9 (2018), pp. 914–924.
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12. Evaluation Lab
Lab Investigations
Recommended
• TSH
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13. Evaluation Lab
Lab Investigations
Recommended
• TSH
Not Recommended
• Anti TPO antibodies
• Calcitonin
• Thyroglobulin
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14. Evaluation Imaging
Scintigraphy
• Only if TSH is suppressed
• To assess the functional status of the
nodule
• Nodules can be hot,cold or
indeterminate
• Hot nodules don’t need FNAC
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15. Evaluation Imaging
Ultrasound thyroid
Who should get an USG?
• All patients with suspected nodules on clinical examination
• All patients with incidentally detected nodules on other imaging modalities -
like CT, FDG PET, MRI
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16. Evaluation Imaging
Ultrasound Thyroid
What is the logic?
• Reduce the number of FNA
• Nodule size and usg characteristics
• Nodules size < USG characteristic
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17. Evaluation Imaging
USG - what questions do we want to answer?
• Is there truly a nodule that corresponds to the palpable abnormality?
• How large is the nodule?
• Does the nodule have benign or suspicious features?
• Is suspicious cervical lymphadenopathy present?
• Is the nodule greater than 50% cystic?
• Is the nodule located posteriorly in the thyroid gland?
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18. Evaluation Imaging
Advantages of USG thyroid
• Pick up subcentimetric nodules
• Targeting in solid - cystic lesion and large lesions
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19. Evaluation Imaging
USG - when not to worry too much?
• Cystic ( > 50 %)
• Spongiform - aggregation of multiple microcystic components in more than
50% of then nodule
• Hyperechogenecity
• Lare coarse / peripheral calcifications
• Puff pastry appearance
• Comet tail shadowing
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20. Evaluation Imaging
Examples of benign nodule findings
Figure: Cyst
Figure: Spongiform
Figure: Comettail
Figure: Macrocalcification
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21. Evaluation Imaging
USG features indicating higher risk of malignancy
• Hypoechogenicity
• Solid composition
• Irregular margin
• Fine micro-calcification
• Absence of halo
• Shape tall more than wide
• Central rather than peripheral blood flow on Doppler US
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22. Evaluation Imaging
USG findings - caveats
FTCs often behave differently
• Round
• Smooth margins
• Iso or hyperechoic
• Non calcified
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23. Evaluation Imaging
Examples of higher risk findings
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24. Evaluation Imaging
Examples of indeterminate findings
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25. Evaluation Imaging
Summary of imaging
Feature Low Risk High Risk
Margins Well defined Ill defined
Shape Regular Irregular
Echogenecity Iso/Hyper Hypoechoic
Microcalcification Absent Present
Structure Cystic Solid
Color doppler flow Peripheral Central
Lymphadenopathy Absent Present
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26. Evaluation Imaging
What is this?
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27. Evaluation Imaging
Risk scoring system -TIRADS
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28. Evaluation Imaging
TIRADS
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29. When to do FNAC?

30. Evaluation Cytology
When to do FNAC?3
TIRADS Stage Size Decision
1 - No
2 - No
3 >25 mm Yes
4 >15 mm Yes
5 >10 mm Yes
3
ACR TIRADS 2017
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31. Evaluation Cytology
Should subcentimetric nodules ever undergo FNA?4
4
DeGroot Endocrinology, 7th Ed, pg 1607
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32. Evaluation Cytology
FNAC
• In all patients who meet the FNAC criteria as mentioned above
• USG guided FNAC > blind FNAC even in palpable nodules5
5
BR Haugen et al. “2015 American Thyroid Association Management Guidelines for Adult
Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid
Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer.”. In:
Thyroid 26.1 (2016), pp. 1–133.
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33. Evaluation Cytology
FNAC - adequacy
• At least six groups of cells each having 10–15 cells
• Approximately 5% will fall into this category in experienced hands
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34. Bethesda system of classification

35. Evaluation Cytology
TIRADS - Bethesda correlation6
6
E Horvath et al. “An ultrasonogram reporting system for thyroid nodules stratifying cancer risk
for clinical management.”. In: J Clin Endocrinol Metab 94.5 (2009), pp. 1748–1751.
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36. Management

37. Management
Management
After the cytology, three categories remain
• Benign - don’t operate (Bethesda 1,2)
• Malignant - operate (Bethesda 5,6)
• Indeterminate (Bethesda 3,4)
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39. Benign nodule - simplified approach

40. Management Indeterminate
The Indeterminate Nodule - Decision making
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41. Management Indeterminate
Bethesda III - pragmatic approach7
7
KG Seshadri. “A Pragmatic Approach to the Indeterminate Thyroid Nodule.”. In: Indian J
Endocrinol Metab 21.5 (2017), pp. 751–757.
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42. Management Indeterminate
Bethesda IV - pragmatic approach
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43. Management Indeterminate
Molecular Testing
Somatic Mutation Panel
• Several genes tested(next
generation sequencing),
including BRAF
• Provides specific information
about individual genes
• Non proprietary
• Useful only when Positive
Gene Expression Classifier
• Based on mRNA expression
levels
• No information on individual
transcripts
• Proprietary
• Useful only when Negative
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44. Management Indeterminate
Molecular Testing
Somatic Mutation Panel
• Several genes tested(next
generation sequencing),
including BRAF
• Provides specific information
about individual genes
• Non proprietary
• Useful only when Positive
Gene Expression Classifier
• Based on mRNA expression
levels
• No information on individual
transcripts
• Proprietary
• Useful only when Negative
SMP vs GEC - no trials
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45. Summary

46. Case Case 1
Case Capsule
• 42 year male presenting with neck mass noted by his wife
• Smoker
• No dysphagia / dysphonia
• Examination - 3 * 2 cm nodule, hard nodule in the left lobe of thyroid
• No palpable neck nodes
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47. Case Case 1
Risk Stratification
History Exami-
nation
Labs Scan FNAC
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48. Case Case 1
Labs
TSH - 3.2 mIU/L
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49. Case Case 1
USG
Figure: Macrocalcification
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50. Case Case 1
USG 8
But your report is descriptive
What’s the TIRADS grade?
Should you do FNAC?
8
www.tiradscalculator.com
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51. Case Case 1
USG 8
But your report is descriptive
What’s the TIRADS grade?
Should you do FNAC?
8
www.tiradscalculator.com
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52. Case Case 1
FNAC
Bethesda 2 nodule
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53. Case Case 1
What next?
• Reassurance
• Clinical follow up
• Repeat USG after 12 - 24 months
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54. Conclusions
Take home points
• Most thyroid nodules are benign
• Risk stratification is the corner stone of management
• Three levels of risk stratification - clinical, radiological and cytological
• Management is teamwork
• Standardization helps in management and capacity building
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55. Conclusions
Recommended Reading
SR Aspinall et al. “How shall we manage the incidentally found thyroid
nodule”. In: Surgeon 11.2 (2013), pp. 96–104.
KJ Bell et al. “Validation of the food insulin index in lean, young, healthy
individuals, and type 2 diabetes in the context of mixed meals: an acute
randomized crossover trial.”. In: Am J Clin Nutr 102.4 (2015), pp. 801–806.
J Chi et al. “Thyroid Nodule Classification in Ultrasound Images by
Fine-Tuning Deep Convolutional Neural Network.”. In: J Digit Imaging
30.4 (2017), pp. 477–486.
C Durante et al. “The Diagnosis and Management of Thyroid Nodules: A
Review.”. In: JAMA 319.9 (2018), pp. 914–924.
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56. Conclusions
Recommended Reading
BR Haugen et al. “2015 American Thyroid Association Management
Guidelines for Adult Patients with Thyroid Nodules and Differentiated
Thyroid Cancer: The American Thyroid Association Guidelines Task Force
on Thyroid Nodules and Differentiated Thyroid Cancer.”. In: Thyroid 26.1
(2016), pp. 1–133.
E Horvath et al. “An ultrasonogram reporting system for thyroid nodules
stratifying cancer risk for clinical management.”. In: J Clin Endocrinol Metab
94.5 (2009), pp. 1748–1751.
EG Keramidas, D Maroulis, and DK Iakovidis. “ΤND: a thyroid nodule
detection system for analysis of ultrasound images and videos.”. In: J Med
Syst 36.3 (2012), pp. 1271–1281.
KG Seshadri. “A Pragmatic Approach to the Indeterminate Thyroid
Nodule.”. In: Indian J Endocrinol Metab 21.5 (2017), pp. 751–757.
Karthik Approach to Solitary Thyroid Nodule 2/2/2019 52 54

57. Conclusions
Recommended Reading
S Tamhane and H Gharib. “Thyroid nodule update on diagnosis and
management.”. In: Clin Diabetes Endocrinol 2 (2016), p. 17.
JP Walsh et al. “Differences between endocrinologists and endocrine
surgeons in management of the solitary thyroid nodule.”. In: Clin
Endocrinol (Oxf) 66.6 (2007), pp. 844–853.
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58. Thank You
karthik2k2
www.medicalruminations.wordpress.com