What is thyroid Nodule? What is the clinical importance? and You Found a Thyroid Nodule: “Now What? ”

1. Approach to:
Thyroid Nodule

2. What is thyroid Nodule?
 Abnormal growth (lump) within the thyroid
gland that can be delineated on imaging
studies from the thyroid parenchyma
(radiologically distinct)
 Thyroid nodule may be solitary, multiple, cystic,
or solid.
 Approximately 25% of solitary thyroid nodules
represent a dominant nodule within a MNG
 Non-palpable nodules detected on imaging
studies are termed incidentally discovered
nodules or “incidentalomas”

3. Thyroid nodules are common
Risk factors
 4 times more common in females
 Increases with age.
 More commonly in areas of iodine
deficiency.
 Cigarette smoking
 Obesity
 Autoimmune thyroid diseases
Can be caused by many disorders
Benign
(colloid nodule, Hashimoto’s thyroiditis,
simple or hemorrhagic cyst, follicular
adenoma and subacute thyroiditis) and
Malignant
(Papillary Cancer, Follicular Cancer, Hurthle
Cell (oncocytic) Cancer, Anaplastic Cancer,
Medullary Cancer, Thyroid Lymphoma and
metastatic tumors

4. What is the clinical importance?
 Thyroid nodules are common
 Malignant potential.
 May cause thyroid dysfunction
 May cause compression
 The high prevalence of thyroid nodules necessitates
the use of evidence-based approaches.
 Special Populations as pregnant patients, children and
patients with multinodular goiter need (different)
management.

5. You Found a Thyroid Nodule:
“Now What? ”

6. Work up
 Generally, all nodules >1 cm should be evaluated,
since they have a greater potential to be clinically
significant.
 Occasionally, there may be nodules <1 cm that
require evaluation because of
 Suspicious sonographic findings,
 Associated lymphadenopathy, or
 Other high-risk clinical factors such as
 a history of childhood head and neck irradiation or
 a history of thyroid cancer in a first degree relative.

7. Work up
Clinically or incidentally discovered thyroid
nodules, requires a combination of clinical
evaluation followed by appropriate investigations-
TSH
+
Thyroid
Scan
or
• CT and MRI neck are for regions can’t be
imaged by US.
• Combined ultrasound and CT may have a
higher sensitivity for gross nodal pathology.
• Thyroidal uptake on (18FDG-PET) scan? for
recurrence or metastasis.

8. A detailed history and physical
examination assessing risk factors
• Male sex
• Age < 20 years or > 70
• Hoarseness.
• Rapid nodule growth
• A history of childhood head and neck irradiation,
• Total body irradiation
• Exposure to ionizing radiation in childhood or
adolescence
• Familial thyroid carcinoma, or thyroid cancer
syndrome in a first-degree relative,
Clinical Findings
• Nodules >4 cm in size
• Hard consistency
• Fixed nodule
• Vocal cord palsy
• Regional lymphadenopathy
• Distant metastases
red flags

9. Work up…..

10.  (TSH) level and thyroid ultrasonography with a
survey of the cervical lymph nodes in all pts.
 A normal or elevated TSH level indicates that
the thyroid nodule is nonfunctioning
 A low or suppressed TSH level suggests the
diagnosis of primary hyperthyroidism, and a
radionuclide thyroid uptake scan (technetium-
99 or iodine-123) should be performed.
 Hyperfunctioning (hot), isofunctioning (warm)
or nonfunctionin (cold) nodule
Work up….. first step?

11. Thyroid ultrasound with survey of the cervical
lymph nodes should be performed in all patients
who have or suspected having thyroid nodules.
Sonography

12. Sonographic Scoring
(ATA) & (ACR)
Thyroid US is the major diagnostic modality for
evaluation of thyroid lesions based on the size of
the nodule, the internal texture, the shape, the
echogenicity, the margin, the presence of
calcification and the presence of adjacent
structures. Stratifying nodules into:
 High suspicion,
 Intermediate suspicion,
 Low suspicion,
 Very low suspicion and
 Benign categories
 American College of Radiology (ACR) has
developed a reporting system for thyroid
nodules known as Thyroid Imaging
Reporting and Data System
(TIRADS) for risk stratification based on
points assigned for composition, shape,
echogenicity, margin and echogenic foci in
the nodule to inform practitioners about
which nodules warrant biopsy.
 (TR1) benign …..II,III,IV…(TR5) highly suspicious

14. American College of Radiology (ACR) TI-RADS classification of
thyroid nodules and management recommendations

16. Office procedure with ultrasound guidance?
 Must get an adequate sample (6 groups of at least 10
cells each – 2 passes minimum)
 Immediate cytopathology helps adequacy
 Thyroid nodule FNA cytology once adequate, should
be reported using diagnostic groups outlined in the:
Bethesda System for Reporting Thyroid Cytopathology
(I….VI)
 Three possible answers:
1. Benign (Bethesda II)
2. Malignant (Bethesda VI)
3. Indeterminate (Bethesda III, IV, V)
Fine Needle Aspiration
Indeterminate

17. Thyroid molecular testing
 Thyroid cancer, like all cancers, is a disease of the genome
(Nuclear atypia). (Initiation/progression of cancer due to the
accumulation of genetic/epigenetic changes)
 A useful tool in conjunction with clinical and ultrasound risk
assessment of thyroid nodules for ruling in or out of cancer in
patients with indeterminate thyroid cytology =20% -25%
(Bethesda category III, IV, and V)
 Reduce the need for diagnostic surgery and guide further
management of the nodules.
 No need for this costly testing if the ultrasound and/or FNA
showed entirely benign or highly suspicious cytology for Ca.
 In differentiated thyroid cancer, identification of aggressive
mutation phenotypes, for more aggressive treatment and close
surveillance of poor prognosis.

18. A) 18FDG-PET imaging is not recommended for the
evaluation of patients with newly detected thyroid
nodules or thyroidal illness,
B) The incidental detection of abnormal thyroid uptake
may be encountered
C) Focal 18FDG-PET uptake within a sonographically
confirmed thyroid nodule carries an increased risk of
thyroid cancer, and fine needle aspiration is
recommended for those nodules.
D) Diffuse 18FDG-PET uptake, in conjunction with
sonographic and clinical evidence of chronic
lymphocytic thyroiditis, does not require further
imaging or fine needle aspiration
18FDG-PET scan

20.  Each nodule >1 cm carries an independent risk of
malignancy and therefore multiple nodules may
require FNA.
 A low or low-normal serum TSH concentration in
patients with multiple nodules may suggest that some
nodule(s) may be autonomous.
 In such cases, a radionuclide thyroid scan should be
considered and directly compared to the US images to
determine functionality of each nodule >1 cm.
 FNA should then be considered only for those
isofunctioning or nonfunctioning nodules with high
suspicion
Multinodular thyroid

21. Thyroid nodules during pregnancy
A) Generally, the diagnostic strategy for thyroid nodules
is similar in pregnant and non-pregnant women
B) Radionuclide scans are contraindicated in pregnancy
C) Fine-needle aspiration biopsy is safe in pregnancy
D) The preferred treatment for pregnant patients with
hyperthyroidism due to toxic nodule is antithyroid
medication.
E) Diagnosis with differentiated thyroid cancer during
pregnancy seem to have a similar prognosis if
surgery is performed during or after pregnancy.
F) Sonographic monitoring over the course of
pregnancy is indicated.

22. Thyroid Ca during pregnancy

23.  About 1% to 2% of children, malignancy rate is as high as 27%,
and require a well-established diagnostic approach;
 Lymphadenopathy and compression signs are the most specific
clinical signs;
 Nodular microcalcifications are the most reliable US risk factors;
 surgery is strongly recommended in all cases with either
positive or suspicious cytological evaluation after FNAB,
 In benign thyroid nodules on FNAB clinical follow-up with serial
physical and US examinations is recommended;
 Surgery might be taken into consideration even in the cases
with previously documented benign lesion on FNAB, when the
strongest clinical and US risk factors are present;
 The most frequent malignant histotype is papillary carcinoma.
Thyroid nodules in children

24. A) Nodules with high suspicion US pattern: repeat US in 6-12
months
B) Nodules with sonographic features of low to intermediate
suspicion US pattern: consider repeat US at 12-24 months.
C) Nodules > 1 cm with very low suspicion US pattern (including
spongiform nodules) and pure cyst: risk not known. If US is to
be repeated, it should be at > 24 months
D) Nodules < 1 cm with very low suspicion US pattern (including
spongiform nodules) and pure cysts do not require routine
sonographic follow-up
E) If a nodule has undergone repeat US-guided FNA with a
second benign cytology result, ultrasound surveillance is no
longer indicated
Follow-up
Nodules with benign FNA cytology