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Approach to a case of Approach to a case of Solitary thyroid Nodule Solitary thyroid Nodule Prof. Abhinav Arun Sonkar (MS, FRCS(Engl), FRCS(Ire), FRCS(glas)FACS, FUICC) Head of department General surgery

Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

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Page 1: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Approach to a case ofApproach to a case ofSolitary thyroid NoduleSolitary thyroid Nodule

Prof. Abhinav Arun Sonkar(MS, FRCS(Engl), FRCS(Ire), FRCS(glas)FACS, FUICC)

Head of departmentGeneral surgery

Page 2: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

DisclaimerDisclaimer

The presenta�on is made solely foreduca�onal purpose, and not for anycommercial purpose.Images, tables and data have been takenfrom various standard textbooks andteaching resources.For queries regarding any data, image ortable, please contact the undersigned.Prof Abhinav Arun SonkarEmail : [email protected]

Page 3: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

ObjectivesObjectives

Definition and Clinical ImportanceClinical featuresInvestigation

- Thyroid function test - Ultrasonography - FNAC - Ancillary Investigations

Page 4: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Objectives continued…Objectives continued…

Surgical Procedure...At the end of the lecture student isexpected to identify a STN & decide itsappropriate management

Page 5: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Thyroglossal duct cyst

Sublingual dermoid cyst

dermoid cyst.

Plunging ranula.

Thyroid swelling at isthmus.

Subhyoid bursa.

Pretrachial, prelaryngeal lymphnodes.

Mid line Neck swellingsMid line Neck swellings

Page 6: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Swelling within Thyroid glandSwelling within Thyroid gland

◦◦◦◦

BenignCollid noduleFollicular adenoma/ Hurthle cell adenomaGraves’/toxic MNG/Toxic adenomaThyroiditis

MalignantCancer from Follicular cell origin

Papillary Thyroid CancerFollicular Thyroid CancerHurthle cell carcinomaAnaplastic thyroid cancer

Cancer from Non Follicular cell originMedullary Thyroid cancer – Sporadic / MEN syndrome (MEN II)Primary Lymphoma

Secondaries – Kidney, breast, lung, colon, melanoma,Prostate

Page 7: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

DefinitionDefinition

◦Thyroid Nodule

A ‘Thyroid Nodule’ is defined as a discrete lesion in thyroidgland which is radiologically distinct from surrounding thyroidparenchyma.

Page 8: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Solitary Thyroid NoduleA ‘Solitary Thyroid Nodule’ is a discrete palpable singlenodule in thyroid gland in otherwise Impalpable gland

Dominant noduleA discrete nodule with nodularity elsewhere in thyroidgland is “dominant nodule”

Page 9: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

EpidemiologyEpidemiology

Incidence of palpable thyroid nodules in adults 1 % in men, 5 % in women

Ultrasonography has increased the incidence of unselected patients (19% to 67%)

Method of detection Study Prevalence

Palpation Tan & Gharib, 1997* 1-5%

Autopsy Wang et al, 1997Mayo clinic study,1955**

49.5%50%

USG Mazzaferri, 1993*** 19-46%

Page 10: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Prevalence on imagingPrevalence on imaging

Imaging modality Detection Rate

USG neck 67 %

CT / MRI 16 %

Carotid Duplex scan 9.4 %

FDG PET 2-3 %

Page 11: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

ChallengeChallengeTo identify patients with clinically significant cancers among large number of patients with Solitary Thyroidnodule.

Page 12: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Every nodule should be considered malignant andeffort should be made to rule out malignancyRisk of malignancy 15 – 20 % aremalignant 80% of STN are benign

.

Page 13: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Characteristics on imagingCharacteristics on imaging

Size more than 1 cm - 67 %

Size more than 4 cm – 38 %

Stage III or IV – 25 %

Positive LN – 30 %

Page 14: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Risk of MalignancyRisk of Malignancy

Risk varies on the modality used andon the imaging characteristics of the nodule.

Risk / Malignancy rate of

impalpable thyroid nodules - same as palpablenodules (4-12%).(Diagnosed on Neck US, CT orMRI )

When diagnosed with FDG PET – risk is 30 %.(more aggressive variant of PTC, unfavourableprognostic factors)

Page 15: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Clinical issues Clinical issues Clinical issues

Possibility of malignancy / diagnostic

dilemma ?

Large enough to be symptomatic ?

Patient’s anxiety about the nature of nodule?

No clear cut protocols till recent past –

potential malpractice liability

Page 16: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

How to evaluateHow to evaluate

◦◦◦

Triple Test –

History & Examination

TFT

Investigations – Ultrasound +/- CT , FNA

History - thorough history regarding risk factors.

Examination – clinical examination of neck especially to lookfor vocal cord paralysis, lateral cervical lymphadenopathy, andfixation of the nodule to surrounding tissues.

Page 17: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

History and examinationHistory and examination

Diagnosis of a Thyroid Nodule should prompt athorough history and examination.

To identify those factors that increase the risk ofthyroid cancer

Page 18: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Risk factors on HistoryRisk factors on History

Male sexAge less than 20 years or greater than 70 yearsRecent onset of hoarseness, dysphonia, dysphagia ordyspnoeaPast medical history of thyroid cancerPrevious head and neck irradiationExposure to nuclear fallout e.g. from ChernobylFamily history of medullary thyroid carcinoma or multipleendocrine neoplasia type 2 (MEN 2)Family history of papillary thyroid carcinoma, familialPolyposis Coli, Cowden’s or Gardner’s Syndrome

Page 19: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Clinical Examina�onClinical Examina�on We start the examination by palpating the cricoid ring

because the isthmus is reliably palpable immediatelyinferior to this.

- fixation to skin/surrounding - firm to hard nodule - neck nodes - vocal cord fixation - features of hyperthyroidism – less malignant chances

Page 20: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Clinical Examina�onClinical Examina�on

◦◦

Inspection – Pizzillo’s methodHands behind head, neck extrendedEspecially in obese persons, short neck Trail sign – tracheal deviation

Palpation – examine fromBehind the patient

Characterize the thyroid swellingLook for Retro-sternal extensionCervical LNTracheal shifting / deviation

Front of the patient –Lahey’s Method – sit in front of patientTo look for Tracheal shifting / deviation

Page 21: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Clinical Examina�onClinical Examina�on

◦◦◦

◦◦◦

Palaption Contd.For trachea

Percussion

Over Manubrium sterni, Heads of clavicleUsually tympanicDull Note in cases of – Retro-sternal Extension(RSE), Central compartmentLN

AusculationOver thyroid superior poles – Bruit + in Graves’ DiseaseTo check Tracheal deviation if present – Bronchial soundsUpper thorax auscultation in cases of Retro-sternal Extension(RSE)

Page 22: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Clinical examina�on contd…Clinical examina�on contd…

A good clinical examination includes A thorough examination of thyroid Examination of anterior and posterior cervical

triangles , lymphadenopathy Size and consistency of nodules

multiplicity / diffuse nodularity benign single firm swelling in older men

malignant

Page 23: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Clinical Examination- HowReliable?

Clinical Examination- HowReliable?

Clinical Examination- HowReliable?

A nodule - located deep within the gland / theposterior surface is difficult to palpate.Even more difficult to palpate nodule in patientswith short and fat neck.Accuracy of thyroid palpation depends on theexperience of the examiner.

Christensen et al (1985) - sensitivity of palpation of

the thyroid gland in terms of size and nodularitywas 38%

Page 24: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Study by Brander and colleagues(1992), -50 % of nodules discovered on ultrasonographyescaped detection on clinical examination;Approx. 1/3rd of nodules that had not been detected bypalpation were > 2 cm in diameter. However a prominent but normal thyroid gland in apatient with a thin neck may be perceived as anabnormality of the thyroid gland

Page 25: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Evalua�on - Thyroid func�on testEvalua�on - Thyroid func�on test

Serum TSH , T3 , T4 to be evaluatedDecreased TSH indicates Hyperthyroidism

indication for an isotope scan (99m Pertechnetate scan) (correlates with lower chances of malignancy in Hot nodule) If Hot Nodule confirmed – No FNAC IndicatedIf Nodule is cold (i.e Rest gland is Hyper functional) – FNAC

is Indicated

Page 26: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

99m pertechnetate scan99m pertechnetate scan

Assessment of functionalcharacteristic of glandHot nodule- 1% malignantCold nodule- 16-20% malignant Done using

I -123 (lingual thyroid & substernal goitreI -131 ( thyroid carcinoma metastasis)

Page 27: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

••

Normal/ High TSHrules out functional nodule ,requires evaluation by USG and FNAC

Normal TSH – Euthyroid Nodule

Increased TSH suggests hypothyroidism ( MCcause - Hasimoto thyroiditis)

Page 28: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Evaluation - ImagingEvaluation - Imaging

◦◦◦◦◦◦

◦◦

Diagnostic ultrasound for thyroid incidentaloma- HRUSGNECK

operator-dependent thoughnon-invasive, accessibleportabilitycost-effectivenesslack of ionizing radiation.allows high resolution imaging of the thyroid (7 – 12 MHz).Gold standardFeatures - size, echogenicity, composition, calcification,margin and halo

Page 29: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Risk stratification on HRUSGRisk stratification on HRUSG

◦◦◦◦◦◦◦

Features correlating with malignancy –HypoechogenicitySolid compositionIrregular maginFine micro calcificationAbsence of haloShape tall more than wideCentral rather than peripheral vascularity onDoppler USG.

Size does NOT seems to correlate with malignancy.

Page 30: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history
Page 31: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

••••

Unfortunately, no ‘single’ US sign has sufficient diagnosticvalue. Kim et al. (2002) stated combination of four signs, capableof diagnosing 94% of thyroid carcinomasmicrocalcifications,a taller-than-wide shape,irregular borders andmarked hypoechogenicity

Brito et al. (2014)highest diagnostic odds ratio for malignancy was being

‘taller than wider’spongiform appearance, cystic nodules – benign , avoid

FNA. .

Page 32: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

US features ofmalignancy

US features ofmalignancy

US features ofmalignancy

hypoechoic

Solid/mixed

microcalcifications

Page 33: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

US features of malignancyUS features of malignancy

Loss ofperipheral halo

Irregularmargins

Page 34: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Colour doppler - USfeaturesColour doppler - USfeaturesColour doppler - USfeatures

Intrinsichypervascularity

Peripheralhypervascularity

Page 35: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

ElastographyElastography

◦◦

new dynamic ultrasound techniquemeasuring tissue stiffness,Principle - Malignant nodule being more hardthan benign.

has great potential to identify malignant solidthyroid nodule.Sensitivity - 97% andPositive predictive value of about 100% in STN

Sensitivity - 97%,Specificity of 92% in multiple nodules.

Page 36: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

TIRADS (THYROID IMAGING- REPORTINGAND DATA SYSTEM )TIRADS (THYROID IMAGING- REPORTINGAND DATA SYSTEM )TIRADS (THYROID IMAGING- REPORTINGAND DATA SYSTEM ) Quantitative assessment of US features,

by Horvath et al. 2009

Page 37: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Evalua�on – Indica�on of CT / MRIEvalua�on – Indica�on of CT / MRI

Not required in the routine work up of STNHuge STN with mass effects – Trachealcompression and deviationEvaluation of local extension in advanced thyroidmalignancyAssessment of retrosternal extension

Post operative follow-up for recurrence

Page 38: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Evaluation - FNACEvaluation - FNAC

1.

2.

3.

4.

Indication of FNA (Revised ATA /AACE Guidelines)High risk features on history – ( age <20, >70ys ; h/o neckirradiation; family h/o MTC/PTC ) Abnormal cervical nodes on clinical examination / USG –>FNA of nodes +/- FNA of TI Suspicious USG features (hypoechoic, microcalcification,irregular border, central vascularity, no halo) Consistency of nodule - solid >1cm, solid <1cm withsuspicious USG,

mixed >2 cm, mixed < 1.5 – 2 cm with suspicious USG )

Page 39: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Fine Needle aspira�on cytology ( FNAC)Fine Needle aspira�on cytology ( FNAC)

Uses a 23 – 26 gauge needleMost cost effectiveInvestigation of choice for STN

( essential for all nonfunctioningdominant nodule > 1cm)Done without image guidance forpalpable nodule and with USGguidance other wise

Page 40: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

FNAC - ClassificationsFNAC - Classifications

Page 41: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Bethesda Classification for thyroidcytopathologyBethesda Classification for thyroidcytopathologyBethesda Classification for thyroidcytopathology

Diagnostic category Risk of malignancy Usual Management

1 Non diagnostic or Unsatisfactory 1- 4 %

Repeat FNA with USGGuidance

II Benign 0 – 3 % Follow upIII Atypia of Undetermined

significance (AUS) orFollicular Lesion ofUndetermined significance (FLUS)

5 – 15 % Repeat FNA

IV Follicular Neoplasm orsuspicious of FollicularNeoplasm

15 – 30 % Lobectomy

V Suspicious of Malignancy 6- - 75 % Total Thyroidectomy

VI Malignant 97 - 99 % Total Thyroidectomy

Page 42: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

Ultrasound guided FNAUltrasound guided FNA

◦◦

recommended forNonpalpable – like in obese people, short neck,scarred neck.Posteriorly located,Previous indeterminate nodule on FNAC

Results in a lower rate of nondiagnostic cytologyand sampling error

Page 43: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

When to evaluate – nodules < 1 cmWhen to evaluate – nodules < 1 cmWhen to evaluate – nodules < 1 cm

nodules less than 1 cm may be evaluated if:Suspicious characteristics on ultrasound;Suspicious lymphadenopathy based on

ultrasound or clinical examinationFamily history of PTC,history of radiation exposure,Prior personal history of thyroid cancerLesions positive on FDG-PET

Page 44: Approach to a case of Solitary thyroid Nodule...Past medical history of thyroid cancer Previous head and neck irradiation Exposure to nuclear fallout e.g. from Chernobyl Family history

ध�यवाद Thank youMerci beaucop GrazieMahalo Gracias