Approach to Thyroid Nodule[1]

APPROACH APPROACH TO TO

THYROID NODULETHYROID NODULE

Dr. (Maj. Gen.) K J ShettyDr. (Maj. Gen.) K J ShettyConsultant EndocrinologistConsultant Endocrinologist

MD, FRCP (Edin.), FICPMD, FRCP (Edin.), FICP

INTRODUCTIONINTRODUCTION

Thyroid Nodule:Thyroid Nodule: – Common Outpatient Clinical ProblemCommon Outpatient Clinical Problem

4 to 8% OF ADULTS4 to 8% OF ADULTS13 to 67% ON USG EXAM13 to 67% ON USG EXAM(Female : Male – 8:1)(Female : Male – 8:1)

– Importance: Concern of CarcinomaImportance: Concern of Carcinoma5% Malignant5% MalignantRelative Common-ness and possibility of complete cure if Relative Common-ness and possibility of complete cure if detected earlydetected early

– Solution:Solution: Evolve a safe, expedient, reliable and cost Evolve a safe, expedient, reliable and cost effective management strategyeffective management strategy

PRESENT SCENARIOPRESENT SCENARIO

Widely Divergent ApproachWidely Divergent Approach– Primary Consultant : GP, Internist, Surgeon, Primary Consultant : GP, Internist, Surgeon,

ENT Specialist, Surgical OncologistENT Specialist, Surgical Oncologist– Bias of the consultant - reluctance to follow guidelinesBias of the consultant - reluctance to follow guidelines– Inadequate use/ Improper prioritization of Inadequate use/ Improper prioritization of

investigative toolsinvestigative tools– Insufficient knowledge of pathophysiology Insufficient knowledge of pathophysiology

natural history of thyroid nodulenatural history of thyroid nodule

indications, merits, and shortcomings of various investigative indications, merits, and shortcomings of various investigative toolstools

Approach to Thyroid NoduleApproach to Thyroid NoduleSteps:Steps:

EvaluationEvaluation – MorphologyMorphology– FunctionalFunctional– ImmunologicalImmunological– CytologicalCytological– HistopathologicalHistopathological

Tools AvailableTools Available– Clinical History & ExaminationClinical History & Examination– Biochemical / Immunological TestsBiochemical / Immunological Tests– Imaging – USG/SCANImaging – USG/SCAN– Aspiration CytologyAspiration Cytology

Thyroid NoduleThyroid NoduleSteps in Evaluation:Steps in Evaluation: – Clinical ExaminationClinical Examination– Biochemical ExaminationBiochemical Examination– Ultrasound EvaluationUltrasound Evaluation– CytologyCytology

Clinical EvaluationClinical Evaluation

AsymptomaticAsymptomaticSymptomaticSymptomaticHyper/ Hypo-thyroidismHyper/ Hypo-thyroidismMechanical Mechanical

DyspnoeaDyspnoeaDysphagiaDysphagiaHoarsenessHoarsenessPainPainRapid Increase In SizeRapid Increase In SizeCosmeticCosmeticPast History (Previous Surgery, Irradiation)Past History (Previous Surgery, Irradiation)Family HistoryFamily History

CLINICAL EVALUATION (cont’d)CLINICAL EVALUATION (cont’d) GeneralGeneral– Sex: M > FSex: M > F– Age: < 20 ; > 60 YrsAge: < 20 ; > 60 Yrs

SystemicSystemic : EUTHYROID/ HYPO/ HYPER : EUTHYROID/ HYPO/ HYPER

NeckNeck : NODULE: SOLITARY / MULTINODULAR : NODULE: SOLITARY / MULTINODULAR– Size/ Intra-thoracic/ ExtensionSize/ Intra-thoracic/ Extension– Consistency: Firm/Hard/CysticConsistency: Firm/Hard/Cystic– Mobile/FixedMobile/Fixed– TendernessTenderness

Lymph nodesLymph nodes : Number and level : Number and level

CLINICAL POINTERS TO MALIGNANCYCLINICAL POINTERS TO MALIGNANCY

Main PointersMain Pointers– Recent Rapid Increase In SizeRecent Rapid Increase In Size– Development of Hoarseness of voiceDevelopment of Hoarseness of voice– Positive Family HistoryPositive Family History– Age & SexAge & Sex– Past History of Neck IrradiationPast History of Neck Irradiation– Hard Fixed NoduleHard Fixed Nodule– Regional lymph nodesRegional lymph nodes

Misconcepts of MalignancyMisconcepts of Malignancy– Size: Smaller Ones – NO RISKSize: Smaller Ones – NO RISK– Multi-Nodular – NO RISKMulti-Nodular – NO RISK– Pain – HIGH RISKPain – HIGH RISK

Biochemical Evaluation Biochemical Evaluation – Lab EvaluationLab Evaluation – First Step: Assess Functional Status – First Step: Assess Functional Status by TFTby TFT– TSH AssayTSH Assay: Most Useful : Most Useful – T3/T4T3/T4: Not Necessary if TSH is normal: Not Necessary if TSH is normal– TSH:TSH:

Absent/ Low - Toxic Nodule : T3/ T4 IndicatedAbsent/ Low - Toxic Nodule : T3/ T4 IndicatedElevated - Hypothyroid : T4 indicatedElevated - Hypothyroid : T4 indicated

– FT3/FT4FT3/FT4: Preferred to TT3/ TT4: Preferred to TT3/ TT4– Thyroid AntibodiesThyroid Antibodies

Thyroid Peroxidase (TPO)Thyroid Peroxidase (TPO)ANTI-THYROGLOBULIN Ab (TgAb) ANTI-THYROGLOBULIN Ab (TgAb) TSH ReceptorTSH ReceptorAntibodies (TSIAb) Graves (Not Routinely Available)Antibodies (TSIAb) Graves (Not Routinely Available)

(Hashimotos and Graves)(Hashimotos and Graves)

Ultrasonography (USG)Ultrasonography (USG)

**High Resolution USG: Exceptional ClarityHigh Resolution USG: Exceptional Clarity*Nodules < 1.5 cm*Nodules < 1.5 cm*Metastatic Nodules In Neck (Clinically not palpable)*Metastatic Nodules In Neck (Clinically not palpable)

• Assists in Localising Nodules for FNAC Assists in Localising Nodules for FNAC • Inexpensive, non invasive, readily availableInexpensive, non invasive, readily available• USG to Endocrinologist USG to Endocrinologist Stethoscope to CardiologistStethoscope to Cardiologist• LimitationLimitation: Little help in differentiating benign : Little help in differentiating benign from cancerfrom cancer

No Single Characteristic: Predictive for malignancyNo Single Characteristic: Predictive for malignancyDenote Higher Risk in combination of some:Denote Higher Risk in combination of some:CompositionComposition Incidence percentage Incidence percentage– SolidSolid 27%27%– Mixed (complex)Mixed (complex) 7% 7%– Pure cysticPure cystic > 4 cm: 6% > 4 cm: 6% < 4 cm: Negligible < 4 cm: Negligible

CalcificationCalcification– Microcalcification : x 3 higher risk without calcificationMicrocalcification : x 3 higher risk without calcification– 95% specificity95% specificity

- Coarse Calcification x 2 Risk- Coarse Calcification x 2 RiskCervical Lymph Nodes : Highly Suggestive of PTC Cervical Lymph Nodes : Highly Suggestive of PTC

Fine Needle Aspiration Cytology (FNAC) / Fine Needle Aspiration Cytology (FNAC) /

Biopsy (FNAB)Biopsy (FNAB) Crucial Step in evaluationCrucial Step in evaluationSimple, safe, accurate and cost effective Simple, safe, accurate and cost effective Assess Reliability Guidelines (Mayo Clinic)Assess Reliability Guidelines (Mayo Clinic)– Experienced, Preferably dedicated cyto-pathologistExperienced, Preferably dedicated cyto-pathologist– Multiple Sites of Aspiration (2-4)Multiple Sites of Aspiration (2-4)– A Low False Negative RateA Low False Negative Rate

Literature 1 – 11 %Literature 1 – 11 %Acceptable < 5%Acceptable < 5%Diagnostic Sample : 2 Slides - > 6 Groups EachDiagnostic Sample : 2 Slides - > 6 Groups Each

> 10 Follicular Cells In each > 10 Follicular Cells In each groupgroup

Benign………………………. 70%Benign………………………. 70%Indeterminate………………..10%Indeterminate………………..10%Malignant…………………… 5%Malignant…………………… 5%Non Diagnostic………………15%Non Diagnostic………………15%

Benign: Colloid NodulesBenign: Colloid Nodules– 70% Simple Cysts70% Simple Cysts– AutoImmune/ Lymphocytic ThyroiditisAutoImmune/ Lymphocytic Thyroiditis

Malignant:Malignant: – Papillary (Commonest) 83%Papillary (Commonest) 83%– Follicular : 11%Follicular : 11%– Medullary (MTC) 5%Medullary (MTC) 5%– Anaplastic Anaplastic 1% 1%

Indeterminate Category: (10%)Indeterminate Category: (10%)

2 GROUPS:2 GROUPS:– Suspicious for malignancy: definitive evidence Suspicious for malignancy: definitive evidence

for malignancy not evidentfor malignancy not evident– Follicular neoplasm: not possible to Follicular neoplasm: not possible to

differentiate from adenoma and carcinoma differentiate from adenoma and carcinoma (capsular/ lymphovascular invasion)(capsular/ lymphovascular invasion)

Both sub-groups qualify for surgeryBoth sub-groups qualify for surgery

Non-Diagnostic (20%)Non-Diagnostic (20%)

Solid LesionSolid Lesion - Insufficient No. of follicular Cells- Insufficient No. of follicular Cells

- Re-Aspiration Indicated after 4 - Re-Aspiration Indicated after 4 weeksweeks

– diagnostic aspirate in 50%diagnostic aspirate in 50%

– if non diagnostic : surgeryif non diagnostic : surgery

Cystic LesionCystic Lesion - Aspirate Unsatisfactory- Aspirate Unsatisfactory

- Solid Component- Biopsy Mandatory- Solid Component- Biopsy Mandatory

- If not feasible - Surgery- If not feasible - Surgery

THYROID SCINTIGRAPHYTHYROID SCINTIGRAPHY

Using Radioactive Iodine (IUsing Radioactive Iodine (I131131) / Technitium (99 mTc)) / Technitium (99 mTc)Depending on uptake classified as:Depending on uptake classified as:– HOTHOT: 5% Toxic Nodule : < 5% Malignant: 5% Toxic Nodule : < 5% Malignant– COLDCOLD: 80 – 85% : 10 – 15% Malignant: 80 – 85% : 10 – 15% Malignant– WARMWARM 10-15% : 9% Malignant 10-15% : 9% Malignant– Expensive/ Availability Only In Special CentresExpensive/ Availability Only In Special Centres– Overlap: Small Nodules MaskedOverlap: Small Nodules Masked

Use Limited ToUse Limited To : :– Indeterminate (Suspicious/Follicular) on FNACIndeterminate (Suspicious/Follicular) on FNAC– Follow Up of “hot” noduleFollow Up of “hot” nodule– Diagnosis of ectopic goitre / Substernal ExtensionDiagnosis of ectopic goitre / Substernal Extension

NORMAL Tc99m THYROID UPTAKENORMAL Tc99m THYROID UPTAKE

HOT NODULEHOT NODULE

COLD NODULECOLD NODULE

MULTI-NODULAR GOITREMULTI-NODULAR GOITRE

MANAGEMENTMANAGEMENT

Based on Combination of Input From:Based on Combination of Input From:– HistoryHistory– Clinical ExaminationClinical Examination– Ultrasound EvaluationUltrasound Evaluation– CytologyCytology

( Benign Nodules, Malignant Nodules, Indeterminate, Nondiagnostic)( Benign Nodules, Malignant Nodules, Indeterminate, Nondiagnostic)

Therapeutic Options:Therapeutic Options:1.1. Follow-Up With Periodic Clinical and lab inputFollow-Up With Periodic Clinical and lab input2.2. SurgerySurgery3.3. RadiotherapyRadiotherapy4.4. Medical therapyMedical therapy

MANAGEMENT (contd….)MANAGEMENT (contd….)

BENIGN NODULES (70%):BENIGN NODULES (70%):– Euthyroid: No Pressure symptoms Yearly Follow upEuthyroid: No Pressure symptoms Yearly Follow up

Cosmetically Acceptable Clinical/Biochem./ USGCosmetically Acceptable Clinical/Biochem./ USG

> 20% > 20% ↑ - Repeat FNAC↑ - Repeat FNAC– Role of Suppressive Rx with T4 – Not ProvenRole of Suppressive Rx with T4 – Not Proven– Beware of subclinical HyperthyroidismBeware of subclinical Hyperthyroidism– Euthyroid: Pressure + Cosmetic Problem – Limited SurgeryEuthyroid: Pressure + Cosmetic Problem – Limited Surgery– Toxic Nodule: Medical (CMZ/PTU Toxic Nodule: Medical (CMZ/PTU ++ Propranolol) Propranolol)

I I 131131 / Surgery / Surgery

MANAGEMENT (cont…)MANAGEMENT (cont…)

Malignant Nodules: 5%Malignant Nodules: 5%

PTCPTC : Total Thyroidectomy with Ipsilateral Central : Total Thyroidectomy with Ipsilateral Central Compartment Lymph Node ClearanceCompartment Lymph Node Clearance

FTCFTC: Non/Min. Invasive – Lobectomy: Non/Min. Invasive – Lobectomy Invasive: Complete Thyroidectomy (Total)Invasive: Complete Thyroidectomy (Total)

Follow Up for BothFollow Up for Both : I : I131131 ablation after 6/52 ablation after 6/52 High Dose Thyroxine High Dose Thyroxine

TSH Suppression (<0.1mu/L)TSH Suppression (<0.1mu/L)MTCMTC: Total Thyroidectomy with complete LN Clearance: Total Thyroidectomy with complete LN ClearanceANAPLASTICANAPLASTIC : Aggressive tumour- TLC/Decompression : Aggressive tumour- TLC/Decompression

MANAGEMENT (cont…)MANAGEMENT (cont…) INDETERMINATE (10%)INDETERMINATE (10%)

FOLLICULAR NEOPLASM / SUSPICIOUS FOR MALIGNANCY

SURGERY WITH INTRAOPERATIVE FROZEN SECTION

TOTAL THYROIDECTOMY

+

LYMPH NODE CLEARANCE

MANAGEMENT (cont…)MANAGEMENT (cont…)

NON DIAGNOSTIC : 20%NON DIAGNOSTIC : 20%

CYSTS : > 4 cm– REPEATED FNAC – NONDIAGNOSTIC/ SURGERY

NODULE – – SURGERY – EXCISIONAL BIOPSY

APPROACH TO THYROID NODULE – AN ALGORITHMAPPROACH TO THYROID NODULE – AN ALGORITHM

USG

CLINICAL EVALUATION+

TFT + IMMUNOLOGY

SOLID COMPLEX CYSTS WITH SOILD COMPUND

PURE CYSTS

FNAC

< 4cm > 4 cm

FOLLOW UP SURGERY

PATIENT WITH THYROID NODULE

EUTHYROID HYPERTHYROID HYPOTHYROID

ANTITHYROID DRUGS/

I 131 ABLATION / SURGERY

T4 REPALCEMENT

FNAC OF NODULE

CYTOLOGY REPORT

BENIGN (70%) MALIGNANT (5%) INDETERMINATE (10%) NON DIAGNOSTIC (15%)

PRESSURE SYMPTOMS/ COSMETIC PROBLEMS – NIL YEARLY FOLLOWUP

SCINTIGRAPHY

(I131/ 99 mTc)Rpt FNAC WITH USG

Rpt FNAC

SUSPICIOUS

WARM COLD DIAGNOSTIC

SURGERY

FOLLOWUP

> 20% INCREASE

SUPPRESSION WITH T4 – 6– 12 MONTHS NON-

DIAGNOSTIC

ALGORITHM (CONTD….)

CONCLUSIONCONCLUSION

Thyroid Nodule- A common ProblemThyroid Nodule- A common Problem

Evaluation: Evaluation: – Arbitrary, Inconsistent, DivergentArbitrary, Inconsistent, Divergent– Based on Personal PreferenceBased on Personal Preference

Long-term experience & advances in Long-term experience & advances in diagnostic aids: diagnostic aids: – Fresh Guidelines laying down systematic Fresh Guidelines laying down systematic

step-wise approachstep-wise approach– Misconcepts correctedMisconcepts corrected

THANK YOUTHANK YOU