EVALUATION OF A THYROID NODULE

VIJAY SHEWALEKIMS , TRIVANDRUM14TH AUG 2013

INTRODUCTION

• DEFINITION- A discrete lesion within the thyroid gland that is palpably and/or radiologically distinct from surrounding thyroid parenchyma.

INTRODUCTION

• PREVALENCE- Epidemiological studies have shown that prevalence of palpable thyroid nodule is 5% in women and 1% in men. This prevalence increases upto 19 – 67 % if detected by ultrasound.

• Nodular goitre prevalence increases by age

INTRODUCTION

• The importance of thyroid nodule rests with the need to exclude thyroid malignancy which occurs in 5 – 15 %

HOW WAS THE NODULE FOUND

• Palpation with a physical exam• Incidental finding on diagnostic work up• Self detection• Surveillance • Work up for symptoms of hyper or

hypothyroidism

CLINICAL EVALUATION

HISTORY

• Age , sex• Swelling in front or side of a neck• h/o pain• Sudden increase in size• Pressure symptoms such as hoarseness of

voice , dyspnoea , dysphagia (rarely)

HISTORY

• h/o hyperthyroid – loss of weight in spite of good appetite, intolerance to heat, excessive sweating

CNS symptoms like- irritability , insomnia, tremor of hands, muscle weakness EYE symptoms such as staring look, difficulty in closing eye, double visionCNS and EYE symptoms are s/o primary

HISTORY

CVS symptoms like palpitations , chest pain , dyspnoea on exertion are s/o secondary hyperthyroid• h/o hypothyroid- increase in weight in spite of

poor appetite, facial puffiness, loss of hair, lethargy, poor memory, constipation, oligomenorrhoea

HISTORY

PAST HISTORY• h/o neck irradiation , • h/o thyroid disease in family

EXAMINATION

General examination-Signs of hyperthyroid- tachycardia, tremor, moist skin, eye signs like exophthalmos look, Von Graefe’s sign, lid retraction, joffroy’s sign,stellwag’s sign, moebius sign

EXAMINATION

Local examination-• Movement of swelling with deglutition• Size , consistency of nodule• Tracheal deviation, retrosternal extension• Cervical lymphadenopathy

WORK UP

THE AMERICAN THYROID ASSOCIATION (ATA) GUIDELINES FOR THYROID NODULE

2009 , REVISED IN 2013

SERUM TSH

• Low TSH may be associated with functioning nodule, very unlikely to be malignant

• TSH has trophic effect on thyroid cancer growth mediated by TSH receptors on tumor cells

• TSH suppression is an independent predictor for relapse free survival in differentiated thyroid cancer

ULTRASOUND SCAN

Can answer following questions• Solid/cystic• size• Additional nodule• Benign or malignant feature

ULTRASOUND SCAN

BENIGN• Iso / hyper echoic• Coarse calcifications• Thin, well defined halo• Regular margins• Hypovascular• No lymph nodes

MALIGNANT• Hypo echoic• Micro calcifications• Thick or absent halo• Irregular margins• Hypervascular• Lymphadenopathy• Taller than wide lesion

HYPOECHOIC

HYPERVASCULARITY

CALCIFICATIONS, POORLY DEFINED, IRREGULAR MARGINS

SOLID

Is size predictor of malignancy

• Non palpable nodules have the same risk of malignancy as palpable nodules with the same size

• Generally, only nodules >1 cm should be evaluated, since they have a greater potential to be clinically significant cancers.

• Nodules <1 cm that require evaluation because of suspicious US findings, associated lymphadenopathy, a history of head and neck irradiation, or a history of thyroid cancer in one or more first-degree relatives.

• Nodules <1 cm lack these warning signs yet eventually cause morbidity and mortality. These are rare and, given unfavourable cost/benefit considerations, attempts to diagnose and treat all small thyroid cancers in an effort to prevent these rare outcomes would likely cause more harm than good.

FNAC

• Only gold standard test for proof of malignancy without surgical pathology

• 23 – 25 gauze no needle is used

INDICATIONS FOR US GUIDED FNAC

• Non palpable or difficult to palpate nodule• Previous non diagnostic cytology• Nodules with previous benign cytology which

has grown in size

FNAC RESULTS

• Nondiagnostic (thy 1)• Benign(thy2)• Suspicious for a Follicular Neoplasm/Follicular

Neoplasm(thy3)• Suspicious for Malignancy(thy4)• Malignant(thy5)

BENIGN

• Scanty normal follicular cells together with colloid

PAPILLARY

• Nuclear grroving• Papillary projections• Orphan annie eye nuclei

FOLLICULAR

• Increased cellularity with a follicular pattern

HURTHLE CELL

• Variant of follicular neoplasm• Oxyphill ( askanazy ) cells predominate

MEDULLARY

• Amyloid stroma

NON DIAGNOSTIC CYTOLOGY

• In persistent non diagnostic cytology risk of malignancy is less than 5%

• Surgery should be considered if nodule is solid

BENIGN CYTOLOGY

• TSH suppressive dose of thyroxine is not recommended

• Repeat us guided evaluation after 6 months• If size same or decrease, continue to follow up

for longer intervals• If increasing us guided cytology• Surgery is recommended in recurrent cystic

nodule with benign cytology

FOLLICULAR NEOPLASM

• I 123 thyroid scan should be considered if serum TSH is in low normal level

• Surgery should be consider if no concurrent hyperfunctioning nodule is present

• Total thyroidectomy if nodule > 4 cm in size bilobar nodular disease h/o radiation exposure or family h/o thyroid malignancy

FOLLICULAR NEOPLASM

• Use of molecular markers such as BRAF, RET/PTC, Ras, PAX8/PPARy or GALECTIN3 may be consider

PAPILLARY

• Total thyroidectomy unless if nodule is less than 1 cm and unifocal

• Modified radical neck dissection only if enlarged lymph nodes are present

MEDULLARY

• Total thyroidectomy• Central compartment lymph node dissection is

recommended• Modified radical neck dissection only if

enlarged lymph nodes are present

ANAPLASTIC

• Total thyroidectomy• Prognosis is poor

LYMPHOMA

• Chemotherapy• Surgery indicated if pressure symptoms are

present

THYROID SCAN

• Only in hyperthyroid• In hot nodule, surgery is recommended after

preparation• In cold nodule ,10 % possibility of malignancy. FNAC is advised, manage accordingly

POST OPERATIVE MANAGEMENT

• In DTC , patient are categorized in high or low risk for recurrence

• AMES (lahey clinic)- age , metastasis, extension , size

• AGES (mayo clinic 1987)- age , grade, extension, size

• MACIS (mayo clinic 1993)- metastasis, age , completeness of resection , invasion, size

POST OPERATIVE MANAGEMENT

• GAMES (MSKCC)- grade , age , metastasis, extension, size

• TNMFOR DTCAge < 45Stage 1 – any T, any N, M0Stage2 - any T ,any N , M1

POST OPERATIVE MANAGEMENT

Age > 45 in DTC and medullaryStage 1 – T1 N0 M0Stage 2- T2 N0 M0Stage 3- T 3 N0 M0 or T 1-3 N1 M0Stage 4A- T4aStage 4 B – T4bStage 4 C – M1

POST OPERATIVE MANAGEMENT

• ANAPLASTICStage 4 A- T 4aStage 4B- T4bStage 4C- T 4c

POST OPERATIVE MANAGEMNT

• In differentiated thyroid carcinoma - Iodine 131 ablation to remove any residual thyroid tissue and malignant cells, to allow follow up with serum thyroglobulin

• Radioiodine scan, serum thyroglobulin, ultrasound scan , to monitor the patients for recurrence

POST OPERATIVE MANAGEMENT

• In medullary ca- radiotherapy recommended if lymph nodes are positive for metastasis

• Tyrosine kinase inhibitors, VEGF receptor inhibitors are under trial now

• Follow up with serum calcitonin , and CEA

THANK YOU