Enrico Papini

Endocrinology and Metabolic Disorder UnitRegina Apostolorum HospitalAlbano Laziale, ItalyAlbano Laziale, Italy

The Following Faculty have provide no information regarding significant relationship with commercial supporters and/or

discussion of investigational or non-EMEA/FDA approved (off-label) drugs as of 5 April 2016

Thyroid Ultrasonography:

Principal Pathologic Principal Pathologic

Findings

Learning Objectives

• To become familiar with ultrasound (US) features

predictive of benign or malignant thyroid disease

• To identify the characteristics of benign and

malignant lymph nodesmalignant lymph nodes

• To review the main ultrasound classification systems

for the risk of malignancy in thyroid nodules and the

indications for fine-needle aspiration (FNA) biopsy.

The growing problem of thyroid nodular disease

• Thyroid nodules are detected by ultrasound (US)

in up to 50% of women

• Most are asymptomatic• Most are asymptomatic

• Main problem is to rule out malignancy.

Gharib H, Papini E. Endocrinol Metab Clin North Am. 2007 Sep;36(3):707-35;

Hegedus L. Clinical practice. N Engl J Med. 2004 Oct 21;351(17):1764-71.

We have US features suggestive of malignancy

Fine Needle Aspiration (FNA) is the best triage

system for malignancy, but…. ….can we perform

FNA on all these nodules?

We have US features suggestive of malignancy

Hypoechoic appearance Irregular margins

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Micro-calcifications More tall than wide shape

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Odds Ratio

� Age, sex, size, and single/multiple lesions have

marginal impact on risk of malignancy

� No single US feature is both sensitive and specific

Differential diagnosis of thyroid nodules

� No single US feature is both sensitive and specific

for cancer

� Part of thyroid malignancies lack suspicious signs

at clinical and US examination.

US Classification Systems may be used to rate the

risk of malignancy and the indication to FNA

•TIRADS 1: normal thyroid gland

•TIRADS 2: benign conditions (0% malignancy)

•TIRADS 3: probably benign nodules (5% malignancy)

•TIRADS 4: suspicious nodules (5–80% malignancy rate)

An US Reporting System for Thyroid Nodules Stratifying

Cancer Risk for Clinical Management

•TIRADS 4: suspicious nodules (5–80% malignancy rate)

4a (malignancy between 5 and 10%)

4b (malignancy between 10 and 80%).

•TIRADS 5: probably malignant nodules (malignancy > 80%)

•TIRADS 6: category included biopsy -proven malignant nodules.

Horvath et s. J Clin Endocrinol Metab, May 2009, 90(5):1748–1751

TIRADS

Classification

Algorithm

Modified (Russ)

Open Journal of

Radiology, 2013 103-

107

- Anechoic lesion

- Thin and regular margins

- No vascular signals

TTII--RADSRADS 22

SIMPLE CYST

- No vascular signals

- No suspicious signs

Hyperechoic spots within

colloid fluid

Diameter 0.5 - 2 mm

TITI--RADS 2RADS 2

“COMET TAIL” SIGN

Diameter 0.5 - 2 mm

Associated with a comet-

tail aspect

Mobile with changes.

- Tiny fluid areas in > 50%

of the nodule

- Isoechoic pattern

TTII--RADSRADS 22SPONGIFORM NODULE

- Isoechoic pattern

- No suspicious signs

- Posterior shadowing

- Isolated

- No tissue component

TTII--RADSRADS 22ISOLATED MACROCALCIFICATION

- No tissue component

- No vascular signals

TTII--RADSRADS 2 2

'White Knight'

Multiple oval/round

hyperechoic areas in a

hypoechoic glandhypoechoic gland

(usually chronic

thyroiditis).

- Hypoechoic

inhomogeneous area

- Blurred margins

TTII--RADSRADS 22

SUBACUTE THYROIDITIS

- Blurred margins

- Frequently multiple

- Scanty vascular signals

- Clinical context

TITI--RADS 3 RADS 3

REGULAR SHAPE

“Wider than taller”

Isoechoic pattern

Well defined marginsWell defined margins

Thin and regular halo

TITI--RADSRADS 4A4AModerate hypoechogenicity

SCORE 4B MARKED HYPOECHOGENICITY

More hypoechoic than superficial muscles

TITI--RADS RADS 4B4BSPICULATED MARGINS

Borders with acute

angles and irregular

marginsmargins

TITI--RADS RADS 4B4BLOBULATED MARGINS

Ondulated borders

At least three small

hubs)hubs)

TITI--RADSRADS 4B4BMICROCALCIFICATIONS

Hyperechoic spots, round or

linear

Diameter ≤ 1 mm

No posterior shadowing (unless

a cluster is present).

TITI--RADS RADS 4B4B"MORE TALL THAN WIDE”

A-P > TR diameter

on transverse scan.

Extracapsular growth

associated with:

- marked

TITI--RADSRADS 55MULTIPLE SUSPICIOUS SIGNS

- marked

hypoechogenicity,

- irregular margins,

- taller-than-wide shape.

Pathologic lymph node

associated with:

- marked hypoechogenicity

TITI--RADSRADS 55MULTIPLE SUSPICIOUS SIGNS

- marked hypoechogenicity

- microlobulated margins

- microcalcifications,

- taller-than-wide shape

� The ATA 2015 Thyroid Nodule and Cancer Guidelines

recommend an US Classification System with 5 major

US patternsUS patterns

� Each class is related to different risk of malignancy

with increasing indication to FNA.

Haugen B et al. Thyroid , January 2016; 26: 1 - 133

The practitioner should identify signs that allow

differentiation of thyroid nodules:

• benign (U2)

British Thyroid Association Guidelines for the Management

of Thyroid Cancer

• benign (U2)

• equivocal/indeterminate (U3)

• suspicious (U4)

• malignant (U5)

Interobserver Agreement in Assessing

the US Features of Thyroid Nodules

AJR:193, November 2009

Stiffness at Elastography

Intranodular vascular signals

Minimally Invasive

Follicular Carcinoma

Classifications may be false friends…

Hyperplastic

Nodule

Abnormal neck

lymph nodes or

extracapsular invasion

2016 AACE/AME/ETA Guidelines

US criteria for US-FNA

Microcalcifications,

Stiffness at

elastography

Solid, deeply

hypoechoic

Mixed cystic / solid

Spongiform

Purely cystic

Hyperechoic

Microcalcifications,

Irregular margins

Announced: May 2016

2016 AACE-AME US Classification

� Low-risk US lesion (US class 1)

� Intermediate-risk US lesion (US class 2)� Intermediate-risk US lesion (US class 2)

� High-risk US lesion (US class 3)

Endocrine Practice 2016 (announced : May 2016)

Low-Risk nodules (US class 1)

A B C

A. Thyroid cyst (fluid component > 80% , regular margins)

B. Mostly cystic nodule with reverberating artifacts, no

suspicious signs

C: Iso-echoic spongiform nodule , regular margins.

A B

C

Intermediate-risk nodules (US class 2)

Slightly hypo- or iso-echoic nodules with smooth margins or halo. May be present:

A. intranodular vascularization: B. elevated stiffness at elastography;

C. coarse or rim calcifications; D. indeterminate hyperechoic spots.

C D

A B

D E

C

F

High-Risk Nodules (US class 3)

A. Marked hypoechogenicity; B. Spiculated or lobulated margins; C. More tall than wide

shape; D. Microcalcifications; E. Extracapsular growth; F. Pathologic adenopathy.

D E F

Lymph-node Structure

hilum

• Presence of hilum

• Long & flat aspect (L/S > 2)

• No suspicious changes

Benign Lymph-Nodes

Normal lymph node:

Central vascularization

From a benign to a malignant lymph node

Malignant node :

Peripheral vascularization

Courtesy of Sato

Rounded appearance and short axis > 5 mm

unsatisfactory (aspecific) predictive criteria

Pathologic lymph nodes

Micro-calcifications

�

�

Pathologic lymph nodes

Cystic Changes

Pathologic lymph nodes

Lymph-nodes « like thyroid tissue »

Vascular Architecture of Benign Nodes

• hilar and longitudinal

• peripherical from longitudinal

vessels

• intranodular «fern» spots

Vascular Architecture of Malignant Nodes

• displacement of longitudinal

vessels and aberrant vessels

• focal absence of perfusion• focal absence of perfusion

• subcapsular vessels (non hilar)

US Characterization of LNSETA 2013

NormalNormal

–– HilusHilus

–– Ovoid shapeOvoid shape

–– Absent or hilar Absent or hilar

vascularityvascularity

IndeterminateIndeterminate

Absent hilus AND 1 of Absent hilus AND 1 of SuspiciousSuspicious

vascularityvascularity Absent hilus AND 1 of Absent hilus AND 1 of

the followingthe following

•• Round shapeRound shape

•• Increased central Increased central

vascularizationvascularization

SuspiciousSuspicious

1 of the following1 of the following

–– MicrocalcificationsMicrocalcifications

–– CysticCystic

–– Peripheral or Peripheral or

diffuse vascularitydiffuse vascularity

–– HyperechoicHyperechoic

Courtesy of L. Leenhardt

Thyroid US: Conclusions

• US is a sensitive exam and may be specific for

thyroid carcinoma (particularly papillary)

• elastography and other techniques may provide

diagnostic informationdiagnostic information

• In many cases no single US feature is diagnostic

for malignancy

• US signs should be used in summation to

determine whether FNA should be performed.

Thyroid US: Conclusion (2)

• US classification systems should be used for

assessing risk of malignancy and guiding actionsassessing risk of malignancy and guiding actions

• Indication for FNA should be evaluated in the

context of patient’s clinical picture.

� High-risk lesions: nodules >10 mm

� Intermediate-risk lesions: nodules >20 mm

� Low-risk lesions: nodules > 20mm AND

Indications for US-Guided FNA

� Low-risk lesions: nodules > 20mm AND

� increasing in size

� symptomatic

� associated with clinical risk factors.

In high-risk nodules with a major diameter 5-10

consider either UGFNA sampling or watchful waiting

on the basis of:

Indications for US-Guided FNA (2)

on the basis of:

� US pattern

� clinical setting

� patient preference.

ThankThank YouYou