Thyroid mass

Thyroid mass Presented by

Dr- Hayam M. AL-moutary

Case

• A 42-year-old woman presents with a palpable mass on the left lobe of thyroid gland

• How to deal with these case?

• She has no neck pain and no symptoms of thyroid dysfunction.

• The patient has no family history of thyroid disease and no history of external irradiation.

• physical examination reveals a solitary, mobile thyroid nodule, 2 cm by 3 cm, without lymphadenopathy

• Which investigations should be performed?

• Assuming that the nodule is benign ,which, if any, treatment should be recommended?

Content

Anatomy& physiology of thyroid glandType of thyroid massApproach patient with thyroid noduleType of thyroid malignancyIodine deficiency disorder (IDD)Management

Thyroid Anatomy• a butterfly-shaped

endocrine gland, located on the anterior (front) side of the neck

• Composed of right & left lob connecting by isthmus

• supplied with arterial blood from the superior thyroid artery and the inferior thyroid artery

Thyroid physiology

Thyroid mass

cancerNodule goiter

Epidemiology • In the United States, 4 to 7 percent of the adult

population have a palpable thyroid nodule.• Nodules are more common in women and increase in

frequency with age and with decreasing iodine intake.• The prevalence is much greater with the inclusion of

nodules that are detected by ultrasonography or at autopsy.

• Malignant nodule corresponds to approximately 2 to 4 per 100,000 people per year, constituting only 1 percent of all cancers and 0.5 percent of all cancer deaths.

Causes of thyroid nodules

• Benign• Multi noduler goiter• Hashimotos thyrioditis• Simple or hemorrhagic cysts• Follicular adenomas• Sub acute thyrioditis

AACE/AME Guidelines 2010

Causes of thyroid nodules

• Malignant• Papillary carcinoma• Follicular carcinoma• Hurthie cell carainoma• Medullary carcinoma• Anaplastic carcinoma• Primary thyroid lymphoma• Metastatic malignant lesion

AACE/AME Guidelines 2010

History

o Ageo Family history of thyroid disease or cancero Previous head or neck irradiationo Rate of growth of the neck masso Dysphonia, dysphagia, or dyspnea

AACE/AME Guidelines 2010

History

o Symptoms of hyperthyroidism orhypothyroidismo Use of iodine-containing drugs or supplements Most nodules are asymptomatic, and absence

of symptoms does not rule out malignancy

Physical Examination

• A careful physical examination of the thyroid gland and cervical lymph nodes

o Location, consistency, and size of the nodule(s)o Neck tenderness or paino Cervical adenopathy The risk of cancer is similar in patients with asolitary nodule or with MNG (Grade B )

AACE/AME Guidelines 2010

Factors suggesting increased risk of malignant potential (grade C):

• History of head and neck irradiation• Family history of MTC or MEN2• Age <20 or >70 years• Male sex• Growing nodule• Firm or hard consistency• Cervical adenopathy• Fixed nodule• Persistent hoarseness, dysphonia, dysphagia, or dyspnea

AACE/AME Guidelines 2010

Laboratory Evaluation

• TSH Assay• Serum Free Thyroxine and Free

Triiodothyronine• Calcitonin Assay

Laboratory Evaluation• Serum TSH should be tested (grade B)• If TSH level is low (<0.5 μIU/mL), measure free

T4 and T3; if TSH level is high (>5.0 μIU/mL), measure free T4 and TPOAb (grade C)

• Serum calcitonin should be measured if FNA or family history suggests MTC (grade B)

AACE/AME Guidelines 2010

UltrasoundIndication of thyroid ultrasound(grade C)1. Palpable thyroid nodule2. History of neck irradiation3. Family history of thyroid carcinoma orMEN24. Patient with unexplained cervical

lymphadenopathy5. Not indicated as screening exam

AACE/AME Guidelines 2010

Fine-Needle Aspiration Biopsy

•Thyroid FNA biopsy has been established as reliable and safe and has become an integral part of thyroid nodule evaluation

•Clinical management of thyroid nodules should be guided by the results of ultrasonographic evaluation and FNA biopsy

Sensitivity 83 % Specificity 92 %

Result of FNASuspicious or indeterminate

Inadequate Malignant or positive

Benign or negative

•cytologic results that suggest a malignant lesion but do not completely fulfill the criteria for a definitive diagnosis

•smears with few or no follicular cells

•primary (thyroid) or •secondary(metastatic) cancers

•colloid nodule•Hashimoto’s thyroiditis

•cyst,•thyroiditis

Thyroid Scintigraphy

•Perform thyroid scintigraphy for a thyroid nodule or MNG if theTSH level is below the lower limit of the

normal range (grade B) In iodine-deficient areas (grade C)

AACE/AME Guidelines 2010

Thyroid Scintigraphy

On the basis of the pattern of radionuclide uptake, nodules may be classified as Hyper functioning (“hot”) Hypo functioning(“cold”)

Thyroid Scintigraphy

Hot nodules almost never represent clinically significant malignant lesions, whereas cold nodules have a reported malignant risk of about 5% to 15%.

Hot & cold nodule

Thyroid nodule

History& physical examination

TSHLow TSH

High or normal

scintigraphy

coldhot

Perform FNAbenign

U/S guided FNA

Benign-veMalignant +ve

Suspicious Inadequate

Repeat FNA Surgery Surgery Observe and repeat FNAC

1 yearOr

levothroxin

Disadvantage Advantage Treatment type

Hospitalization, high cost, vocal cord paralysis ,hypothyroidism

Relief symptom & nodule surgery

Reduce bone density, arrthmia No need hospitalization , low cost, prevent new

nodule to growth

Levothroxin

Use contrceptive , hypothyridism Risk of thryioditis

No need for hospitalizationLow cost, decrease nodule

40% in 1 year

Ridioidoin

Pain full , vocal cord paralysis, No need for hospitalizationLow cost, decrease nodule

45% in 6 month

Ethinol injection

Laser therapy

Thyroid Malignancies- Papillary

• Most common• 30% have node metastasis at diagnosis• Radiation related• Histologically, psammoma bodies

distinguish from benign adenoma.

Thyroid Malignancies-Follicular

• 20 % of malignancies• Distinguished from normal follicular

adenomas by invasion of capsule or blood vessels.

• May be difficult to determine on FNA

Thyroid Malignancies- Medullary

• 5-10% of cases• arise from the C cells which produce calcitonin• diagnosis based on elevated thyrocalcitonin

levels and thyroid nodule (cold)

Thyroid Malignancies- Anaplastic

• < 10%• Highly aggressive with local extension at time

of diagnosis.• No suitable therapy• Prognosis < 1 yr from diagnosis

Iodine Deficiency• Iodine is a chemical element. It is found in

trace amounts in the human body, in which its only known function is in the synthesis of thyroid hormones

• Severe iodine deficiency results in impaired thyroid hormone synthesis and/or thyroid enlargement (goiter).

• More common in female

iodine deficiency disorders (IDDs), include

endemic goiter, hypothyroidism, cretinism, decreased fertility rate, increased infant mortality, mental retardation.

pathophysiology

• Normal dietary iodine intake is 100-150 mcg/d.

Clinically • HistoryGoiter - Patients with IDD most commonly

present with goiterHypothyroidism - Individuals with severe

iodine deficiency may also have hypothyroidism and may complain of fatigue, weight gain, cold intolerance, dry skin, constipation, or depression

• Cretinism . Cretinism can be divided into neurologic and myxedematous subtypes. Both conditions can be prevented by adequate maternal and childhood iodine intake. – Neurologic cretinism is thought to be caused by severe IDD

with hypothyroidism in the mother during pregnancy and is characterized by mental retardation, abnormal gait, but not by goiter or hypothyroidism in the child.

– Myxedematous cretinism is considered a result of iodine deficiency and hypothyroidism in the fetus during late pregnancy or in the neonatal period, resulting in mental retardation, short stature, goiter, and hypothyroidism

Physical

The first sign of iodine deficiency is diffuse thyroid enlargement, which becomes multinodular over time.

In patients with hypothyroidism due to severe iodine deficiency, one might see signs such as dry skin, periorbital edema, and delayed relaxation phase of the deep tendon reflexes.

Laboratory Studies

• The kidneys excrete approximately 90% of ingested iodine

• median 24-hour urine iodine collection• random urine iodine-to-creatinine ratio 50-100 mcg of iodine per liter mild iodine deficiency 20-49 mcg of iodine per liter moderate deficiency less than 20 mcg of iodine per liter severe deficiency

Other Tests T4 T3

TSH

normal or decrease

normal or slightly elevated

normal to increased

euthyroidism and iodine deficiency

decreased decreased increased hypothyroidism

Treatment

• non-pharmacologicalDiet The WHO recommendations for iodine intake

are 150 mcg/d for adults and adolescents200 mcg/d for pregnant or lactating women,

• PharmacologicalPotassium iodide (Lugol solution, SSKI, Pima)Levothyroxine (Synthroid, Levothroid, Levoxyl)12.5-50 mcg/d PO and increase by 25-50 mcg/d

PO q2-4wk, not to exceed 100-200 mcg/d PO• Surgery

Summary

• Most nodules are asymptomatic, and absence of symptoms does not rule out malignancy

• The initial evaluation should include measurement of the serum thyrotropin level and a fine-needle aspiration, preferably guided by ultrasonography

• IDD are common in our region can be preventable by take recommended dose of iodine from natural source

Reference

e medicineAACE/AME Guidelines 2010Swansons family medicine review 6th edition