This document provides an overview of the approach to evaluating and managing solitary thyroid nodules. It discusses the epidemiology, risk stratification, clinical and laboratory evaluation, imaging with ultrasound and scintigraphy, cytology using the Bethesda system, and management approaches for benign, indeterminate, and malignant nodules. A case example is presented of a patient with a benign nodule based on ultrasound characteristics, TIRADS score, and cytology results. Key points are that risk stratification guides evaluation and management, and a multidisciplinary team approach is important for standardized patient care.

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.
Karthik Approach to Solitary Thyroid Nodule 2/2/2019 51 54

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