Prepared by : Hossam Mohammed MahmoudSupervised by : Dr . Naser Zaghloul

SOLITARY NODULE THYROID

DEFINITION:-

DISCREAT SWELLING IN AN OTHERWISE IMPALPABLE GLAND

IntroductIon

* In the general population, thyroid nodules are discovered by palpation in 3% to 7%, and by US in 20% to 76% . * palpable thyroid nodule is 5% in women and 1% in men . * 5- 15 % of them are malignant . * Prevalence increases directly with age, exposure to ionizing radiation, and iodine deficiency

* 4-7 % of adults have palpable thyroid nodule

* 1 of 20 is malignant .

* 50 % of 60 years old persons have thyriod nodules .

In uSA :

rISk fActorS of mAlIgnAncy History Physical examination

Age <20 or >70 years larger than 3 cm

Male sex Rapid tumor growth

History of childhood head/neck irradiation

Very firm nodule, irregular surface

Family history of PTC, MTC, or MEN2

Fixation to adjacent structure

Cervical lymphadenopathy

Cold nodule on thyroid scan

Solid or complex cyst on US

fActorS SuggeStIng benIgn thyroId nodule

F.Hx of autoimmune disease (Hashimoto’s thyroiditis)

F.Hx of benign thyroid nodule or goiter

Presense of thyroid hormone dysfunction,

hypothyroid or hyperthyroid

Pain or tenderness associated with nodule

Soft, smooth, mobile

MNG without a predominant nodule

Warm nodule on thyroid scan

Simple cyst on US

Etiology Benign Malignant

Dominant nodule of a multinodular goitre.

Primary : Follicular cell-derived

carcinoma:PTC, FTC,

anaplastic thyroid carcinomaC-cell–derived carcinoma:

MTCThyroid lymphoma

Colloid nodule Secondaries : Metastatic carcinomaHashimoto’s thyroiditis

Simple or hemorrhagic cyst

Follicular adenoma

Subacute thyroiditis

Autonomous toxic nodule

Plummer’s Disease

ManagEMEnt (1) History

(2) Examinations . (3) Investigations

(4) Treatment .

* Personal * Present * past * Family

* Laboratory * Radiological * Biopsy

(1) History :Personal Present Past Family

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* 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 vision .

h/o neck irradiation

h/o thyroid disease in family

Ex : - autoimmune

disease - carcinoma

(2) ExaMinations : Factors suggesting malignancy :

* larger than 3 cm * hard with irregular surface * Fixed * Cervical lymphadenopathy

Factors suggesting benign nodule :

* Pain or tenderness associated with nodule

* Soft, smooth, mobile

(3) invEstigations : Laboratory :

⃝ 1 - Thyroid functions test : TSH level ( N : 0.5-6 uU/ml )

Hyperthyroid ( ↓ TSH )( hyper-functioning)

radionuclide imaging(scan)

Euthyroid (Normal

TSH )

Hypothyrioid ( ↑ TSH )

You must ask for :

⃝ 2 – Serum Antibodies :Anti-thyroglobulin , anti-peroxidase

To exclude Hashimoto’s+

FNABC ( 5 % turn to lymphomas )

N.B : scan is only indicated in : 1-is suppressed TSH2-if FNAC→follicular neoplasia

⃝ 3 – If there is family history of Medullary carcinoma OR MEN-II ( not routinely done ) ask for : 1- serum calcitonin 2- serum Calcium 3- urinary catecholamines

N.B : screening in familial type is by calcitonin level , If High we do total thyroidectomy even normal thyroid function .

Imaging :

⃝ 1 – Ultrasound :

* Can answer following questions

* Solid/cystic

* Size of the nodule and size of gland .

* Additional nodules

* malignant feature

* Can guide in: FNACB , cyst aspiration, ethanol injection , and laser therapy .

Hypo echoic , Micro-calcifications , Irregular margins , Hypervascular (by doppler ) ,

Lymphadenopathy

Hypo-echoic Hyper-vascular

-CALCIFICATIONS,- POORLY DEFINED- IRREGULAR MARGINS

Imaging :

⃝ 2 – Radionuclide scan :

Using Iodine131 OR Technetium-pertechnetate 99m.

* cold nodule ( non-functioning ) (90%) : cancer risk 5- 10 %* hot nodule (functioning ) (10 %) : cancer risk 1%

Only in hyperthyroid ( suppressed TSH )

* Not useful in distinguishing benign and malignant lesions since majority of cold nodules are benign (80%) and some warm nodules are malignant (5%)

* It can reveal retrosternal extension .

Cold nodule Hot nodule

Other imaging methods MRI , CT Rarely indicated.Only to evaluate retro-sternal extension .

PET scan using FDGf18 (fluorodeoxyglucose F18 )

It can differentiate benign from malignant

But

Highly expensive and can

not replace biopsy

(3) FNACB the most direct and most specific Sensitivity: 70-90% ( after 2-4 passes of needle ) , specificity :70-

90% False negative result: 1-6 % Reliability depend on: Operator , Cytopathologist can not differentiate between follicular adenoma and carcinoma should guided with sonar . Findings :

+ve ( malignant ) - ve ( benign )

- Commonest is PTC- MTC-anaplastic carcinoma- metastatic cancers

- Colloid nodule-Macrofollicular adenoma-Lymphocystic thyroiditis-Granulomatus thyroiditis -Benign cyst

Suspicious

-Follicular neoplasms -Hürthle cell neoplasms -Atypical PTC - Lymphoma

ImmuNohIstoChemICAl mArkers

HBME-1 (Hector Battifora mesothelial cell -1 )

monoclonal antibody stains papillary cancer positively but

does not stain benign follicular tumors Galectin-3

acts as a cell-death suppressordistinguish benign from malignant

thyroid follicular tumors

TreaTmenT opTions : 1- Levothyroxine : ( in benign nodule ) to keep TSH below

0.1 mU/L

Have many Side effects , so not recommended

2- surgery : indicated in :

- FNAC positive or clinically suspicious : ( eldery ,male , hard texture

, fixed , recurrent laryngeal nerve palsy , lymphadenopathy ,

recurrent cyst

- Cosmosis - Toxic nodule - Pressure symptoms

**methods * Lobectomy + isthemusectomy: In pt with

low risk factors & Benign

* Total thyroidectomy: In pt with high risk factors

Benign nodules & Malignant nodules

3- Radioiodine : indicated in functioning nodule, contraindicated in pregnancy , lacatation , children . S/E : hypothyroidism , carcinogenic , fetal anomalies in pregnant women .

4- Percutaneous ethanol injection , and laser photocoagulation .

* Guidelines : according to American Thyroid Association 1996

& American Association of Clinical Endocrinology Radionuclide scan is only indicated in :

1 - suppressed TSH

2 - if FNAC → follicular neoplasia FNAC should be guided by U/S especially if the nodule is

partially cystic . benign nodule → Life long Follow-up every year by

( TSH , neck palpation , FNAC ) , if functioning : Iodine -131 is TTT of choice , and Surgery is indicated in :

- very large nodule , OR - partially cystic , - young patient , pregnant

malignant nodule → surgry Autoimmune thyroidits → cortison + L-thyroxin Infections → control .

Revised American Thyroid

Association Guidelines

2009