This document provides guidance on evaluating and managing thyroid nodules. It discusses that thyroid nodules can have a variety of causes, from benign neoplasms to malignant cancers. The key investigations for evaluation are ultrasound, FNAC, and molecular/genetic testing if needed. Factors like nodule size, characteristics on ultrasound and cytology results determine the risk of malignancy and need for surgery. Ongoing surveillance of nodules is also addressed based on risk level. The goal is to identify malignant nodules while avoiding unnecessary surgery for benign lesions.

1. Prof Dr MP VISWANATHAN
Prof Dr D SURESH KUMAR

2.  A isolated thyroid nodule is a discrete lesion within the
thyroid gland that is radiologically distinct from the
surrounding thyroid parenchyma
 DOMINANT swelling in a gland with clinical evidence of
generalised abnormality in the form of a palpable
contralateral lobe or generalised mild nodularity.
 About 70% of discrete thyroid swellings are clinically
isolated and about 30% are dominant
 Incidentalomas-Nonpalpable nodules incidentally
detected on US or other anatomic imaging studies

3. Incidence increases with advancing age.
A feature of many different Thyroid diseases
ALWAYS DIAGNOSTIC DILEMMA.
SNT OR SNG IS SLIGHTLY MORE PRONE
FOR MALIGNANCY THAN MNG.

4.  only nodules >1 cm should be evaluated- a greater
potential to be clinically significant cancers
 Nodule < 1 cm – should be evaluted if asso with clinical
symptoms or associated lymphadenopathy

5.  Complete history
 Physical examination

6.  Young patients (< 20 yrs age) or old (> 70 yrs age)
 Male sex
 H/O external neck radiation during childhood
 WBRT
 RADIATION FALL OUT
 familial thyroid carcinoma
 thyroid cancer syndrome (PTEN, FAP, Carney complex, Werner
syndrome/progeria) or MEN 2
 MTC in a first degree relative
 rapid nodule growth
 hoarseness
 Recent change in voice, difficulty in swallowing
 Hard, irregular
 FIXITYty, regional lymph nodes

8.  SERUM TSH
 ULTRASONOGRAPHY
 FNAC
 THYROID SCAN
 CECT/MRI
 PETCT

10.  SUBNORMAL –RADIONUCLIDE SCAN
• hyperfunctioning (‘‘hot,’’)
• isofunctioning (‘‘warm,’’)
• nonfunctioning (‘‘cold,’’)
 HIGH SERUM TSH –Risk of malignancy
 serum THYROGLOBULIN (Tg) ,CALCITONIN for initial
evaluation of thyroid nodules is NOT
RECOMMENDED

11. • Cold nodule - Non functioning
• Warm nodule - Normal functioning
• Hot nodule - Hyper functioning

12. • More than 80% of the nodules are cold but fewer than
20% of these are malignant.
• About 10% are warm and 10% of these are malignant
• Only 5% of the scans have hot nodules with fewer
than 5% malignancy.

14.  composition (solid, cystic proportion, or
spongiform)
 Echogenicity
 Margins( infiltrative, microlobulated, or spiculated)
 presence and type of calcifications
 Shape (taller than wide)
 Vascularity

15.  PTC
 FTC & FVPTC –Different sonographic features
 Iso- to hyperechoic
 noncalcified
 round (width greater than anterioposterior
dimension) nodules
 regular smooth margins

16.  identifies as small as 0.3cm sized nodules.
 discriminate cystic from solid lesions.
 15 to 25% of all thyroid nodules are cystic
 cyst size > 4cm - malignancy rate around 20%
 Detects lymphnodal involvement

19. FNAC
KEY INVESTIGATION OF CHOICE
PERFORMED BY PALPATION OR US GUIDANCE
* Simple / Excellent patient compliance, quick, can be readily
repeated, highly accurate, cost effective, low morbidity.
* NO FALSE POSITIVITY / FALSE NEGATIVE RATE 2.2%

20.  the presence of at least six groups of well-
visualized follicular cells, each group
containing at least 10 well-preserved
epithelial cells, preferably on a single
slide

22. Thyroid nodule FNA cytology should be
reported using diagnostic groups outlined
in the Bethesda System for Reporting
Thyroid Cytopathology

24. FNAC
Can accurately diagnose
•Colloid Nodules.
• Thyroiditis.
• Papillary carcinoma.
• Medullary carcinoma.
•Anaplastic carcinoma.
•Lymphoma
Limitation - Inability to distinguish benign from
malignant follicular Neoplasms.

25. Molecular Markers in FNAC
Finding the BRAF mutation, RET/PTC rearrangements in
an indeterminate FNAC specimen have been correlated with
a 100% specificity of thyroid cancer in a recent prospective
study.
•Immuno cytochemical technique for the detection of
THYROID PEROXIDASE( TPO ) may be a useful adjunt to
FNAC in the preoperative diagnosis of follicular malignancy.
 BRAF & RAS are currently the most widely prevalent &
studied mutations utilized for making clinical decisions.

26.  REPEATED WITH US GUIDANCE and, if available, on-site
cytologic evaluation
 Without a high suspicion sonographic pattern require
CLOSE OBSERVATION OR SURGICAL EXCISION for
histopathologic diagnosis
 SURGERY INDICATED
• High suspicion sonographic pattern
• growth of the nodule (>20% in two dimensions) in US
surveillance
• clinical risk factors for malignancy -

27.  DIAGNOSTIC STUDIES OR TREATMENT ARE NOT
REQUIRED

28. Molecular markers
 Thyro seq V 3
 167 GEC (SENSITIVITY 92%NPV 93%)
 GALECTIN 3 IHC
 NEXT GEN SEQUENCING
 18FDG-PET imaging is not routinely recommended for
the evaluation of thyroid nodules with indeterminate
cytology.
 IF MARKERS NOT DONE OR NOT AVAILABLE –SURGERY OR
OBSERVATION –DEPENDING UPON RISK FACTOR

29.  ThyroSeq v3 –sensitivity and specificity of 94% and 82% &
NPV and PPV of 97% and 66% - and the highest rate of
identification of Hurthle cell adenomas (62%) and Hurthle Cell
Carcinoma in 100%.
 Afirma GEC – Gene Expression Classifier -excellent sensitivity
and NPV - (90% and ∼95% respectively), poor specificity and
PPV, ∼50% and 38%, respectively) for Bethesda III and IV nodules
 Afirma Genomic Sequence Classifier (GSC)- sensitivity,
specificity, NPV, and PPV of 91%, 68%, 96%, and 47%,
respectively – Weak in detecting Hurthle cell neoplasms
These are currently applied to Bethesda III (AUS/FLUS and
Bethesda IV lesion to decide on observation vs lobectomy
bearing in mind their fallibility and cost.

30.  SURGICAL MANAGEMENT should be similar to that
of malignant cytology

31.  THYROID LOBECTOMY
 TOTAL THYROIDECTOMY
 positive for known mutations specific for
carcinoma
 sonographically suspicious
 large (>4 cm)
 familial thyroid carcinoma
 history of radiation exposure

32.  ability to treat multifocal tumour
 Decreases local recurrence.
 Decreases distant recurrence
 Reduces the risk of anaplastic conversion in remaining
remanants.
 Facilitates treatment with I131
 Permits Post-op-thyroglobulin measurement.

33. Suspected tracheal involvement either by invasion or compression
Bukly nodal disease
Extension into the mediastinum (retrosternal lesions)
Recurrent disease

34.  Elastography is a measurement of tissue stiffness.
 USE can only be effectively applied to solid
nodules, thus excluding its utility for cystic or
partially cystic nodules
 Performance of USE was inferior to that of gray-
scale US assessment –NOT RECOMMENDED

35.  UPTAKE –FOCAL OR DIFFUSE
 FOCAL – INCREASED CHANCE OF MALIGNANCY
 DIFFUSE –THYROIDITIS

36.  Nodules with high suspicion US pattern: repeat US
and US-guided FNA within 12 months.
 Low to intermediate suspicion US pattern: repeat
US at 12–24 months
 very low suspicion US pattern (including
spongiform nodules) it should be done at ‡24
month

37.  Routine TSH suppression therapy for benign thyroid
nodules in iodine sufficient populations is NOT
RECOMMENDED
 Inadequate dietary intake is found or suspected, a daily
supplement (containing 150 lg iodine)
 Surgery for growing nodules, (>4 cm),compressive or
structural symptoms
 Recurrent cystic thyroid nodules with benign cytology -
surgical removal or percutaneous ethanol injection (PEI)
based on compressive symptoms and cosmetic concerns

38. Benign Thyroid
Neoplasm
• Follicular
Adenoma
• Papillary
Adenoma
• Teratoma
• Lipoma
Malignant Thyroid
Neoplasm
• Papillary
carcinoma
• Follicular
Carcinoma
• Medullary
Carcinoma
• Anaplastic
Carcinoma
• Lymphoma
• Metastatic
Cancer
Other thyroid
Abnormalities
• Thyroditis
• Thyroid cyst
• Infection