2. Evaluation Thyroid Nodule.pptx

Diagnostic Procedure of Thyroid Nodule

Nanang Miftah Fajari Perkeni Cabang Banjarmasin Sub Bag Endocrinologi Metabolisme dan Diabetes RSU Ulin Banjarmasin

Epidemiology • Increases with age – Autopsy : 9th decade  80% women, 65% men

• Palpable thyroid nodules  4-7% of population • Prevalence 19-67% - based on nodules found incidentally on ultrasound • 4:1 women:men • Geographic areas with iodine deficiency • Thyroid carcinoma in 5-10% of palpable nodules

Presentation • Majority are asymptomatic • <1% cause hyperthyroidism • Neck pressure or pain if spontaneous hemorrhage

Clinical Evaluation Of Thyroid Nodule Anamnesa : • History of present illness • PMHx – postpartum – Past Hx of thyroid pain/tenderness/nodule/ enlargement or goiter – H/O autoimmune diseases • FamHX – thyroid dysfunction, thyroid cancer, Autoimmune diseases. • Medications Systematic physical exam Laboratory Testing Imaging FNAB DON’T FORGET THE BASICS

History • Symptoms of hyper or hypothyroidism • Previous nodules, goiters, family history of autoimmune thyroid disease, thyroid carcinoma, or familial polyposis • Hashimoto’s thyroiditis – association with thyroid lymphoma

History – Red Flags • • • •

Male < 20 years, > 65 years Rapid growth of nodule Symptoms of local invasion (dysphagia, neck pain, hoarseness) • Hx of radiation to head or neck • Family hx of thyroid CA or polyposis

Physical Exam • Less than 1 cm usually not palpable • ½ of all nodules detected by ultrasonography not detected by physical exam • Should also examine for lymphadenopathy

Physical Exam

Clinical Exam. of Thyroid •

Have patient seated on a stool / chair

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Inspect neck before & after swallowing

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Examine with neck in relaxed position

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Palpate from behind the patient

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Remember the rule of finger tips

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Use the tips of fingers for palpation

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Palpate firmly down to trachea

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Pemberton’s sign for RSG

EXAMINATION OF A THYROID SWELLING • INSPECTION : by Pizillo’s method – size, shape and location and borders, surface – look for redness, scar, dialated vein pulsation, sinuses.

• Palpation : measure size, shape, consistency, mobility – Lahey’s method for palpation of deep surface – Crile’s method for small nodules – kochers test for stridor – berry’s sign for carotid pulse

• Percussion : Dull note if retrosternal extension • Auscultation: bruit

Laboratory Testing 1. Thyroid Function Test • TSH – first-line serum test – Identifies subclinical thyrotoxicosis • T4, T3 • Do not use thyroid function tests to differentiate benign from malignant

2. Calcium 3. Thyroglobulin – Post-treatment good to detect recurrence 4. Calcitonin – only in cases of medullary 5. Antibodies – Hashimoto’s 6. RET proto-oncogene

Lab Tests For Thyroid Function

Thyroid Function Test

TSH Measurement

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Immunometric Assays - Analytical Sensitivity (CV
Radiology • Ultrasound – to document size, location, and character of nodule – To determine changes in size of nodules over time or to detect recurrent lesions – U/S guided biopsy decreases the incidence of indeterminate specimens

Thyroid U/S Benign Characteristics

Malignant Characteristics

Regular border Halo (sonolucent rim)

Irregular border No Halo

Hyperechoic

Hypoechoic (more vascular)

Egg shell calcification

Microcalcification

N/A

Intranodular vascular spots (color doppler)

Thyroid US

ATA 2015

Sonographic Patterns and Malignancy Risk

Radiology • Thyroid scan – Can not reliably distinguish benign from malignant nodules – Cold nodules – 5-15% are malignant – Hot nodules – almost always benign

Thyroid Scan Thyroid nodule: risk of malignancy 6.5% only 5-10% of nodules

Cold nodule

16-20% malignant

“Warm” Nodule

(indeterminant) 5% malignant

Hot Nodule

Tc-99m < 5% malignant I123 < 1% malignant

Fine-Needle Aspiration Biopsy • Emerged in 1970s – has become standard firstline test for diagnosis • Safe, efficacious, cost-effective • Allow preop diagnosis and therefore planning • Sampling errors in very large and very small nodules – minimized by u/s guided biopsy

Fine Needle Aspiration (FNA) • • • • • •

25G Needle, 10cc syringe Done in Office +/- Local 3-5 passes SEN 95-99% (False Negative rate 1-5%) SPEC > 95%

Hasil FNAB Pasien Thyroid Nodule di RS Ulin 2018

Hasil FNAB RS Ulin

The Bethesda system for reporting thyroid cytopathology

Signs and Symptoms Suggestive of Malignancy

Algorithm for Thyroid Nodule Thyroid Nodule Low TSH

Normal TSH

TC 99 Nuclear Scan Hot Nodule RAI Ablation, Surgery or ATD

FNAC or US guided biopsy

Cold Nodule 4% Malignant

Surgery

10%

69%

Suspicious or follicular Ca

Benign

T4 suppression

Cyst

17% Non diagnostic – repeat FNAC

Surgery or Cytology

Summary • Thyroid nodules are common, but only about 5% are malignant • Urgent referral to secondary care is necessary only if the nodule is growing rapidly (over few weeks) or associated with stridor, hoarseness, or cervical lymphadenopathy • Needle aspiration biopsy is the most accurate method of investigation. Its accuracy is improved by ultrasound guidance. • Ultrasonography can also add useful information and can improve accuracy.