Thyroid goiter Flashcards
Define a thyroid goiter
Abnormal enlargement of the thyroid gland
Name common causes of thyroid goiter
Iodine deficiency
Autoimmune disorders
- Hashimotor’s
- Grave’s
Other
- thyroid cyst
- thyroid adenoma
- thyroid carcinoma
- ingestion of goitrogens
- congenital
- pituitary adenoma
Define a thyroid nodule
A discrete lesion within the thyroid gland that is radiologically distinct from the surrounding normal thyroid parenchyma
Name clinical features of hyperthyroidism
- Ocular
- lid lag
- lid retraction
- Grave’s ophthalmopathy (exophthalmos, periorbital edema) - Vocal
- tremulous voice - Dermatological
- warm, moist skin
- hyperhidrosis
- pretibial myxedema
- fine hair
- diffuse hair loss
- onycholysis - Thyroid
- diffuse smooth, non-tender goiter
- audible bruit (Grave’s) - Metabolic
- heat intolerance
- weakness
- fatigue
- weight loss - CVS
- tachycardia
- palpitations
- hypertension with widened pulse pressure
- atrial fibrillation
- chest pain - MSK
- hyperthyroid myopathy
- osteopathy - GIT
- frequent bowel movements - Reproductive
- females (amenorrhoea, anovulation, dysfunctional uterine bleeding)
- males (gynecomastia, libido issues, infertility ED) - Neuropsychiatric
- anxiety
- restlessness
- insomnia
- tremors
- hyperreflexia
Name symptoms of hypothyroidism
- Ocular
- periorbital edema - Vocal
- hoarse voice
- dysarthria - Dermatological
- cold, dry skin
- hypohydrosis
- coarse hair
- hair loss
- brittle nails - Thyroid
- goiter
- atrophic - Metabolic
- cold intolerance
- fatigue
- weight gain - CVS
- bradycardia
- myxedematous heart disease (dilated cardiomyopathy, dyspnea)
- decreased CO - MSK
- hypothyroid myopathy
- entrapment syndromes
- myoedema - GIT
- constipation - Reproductive
- females (abnormal menstruation, galactorrhea)
- males (ED, decreased libido, infertility) - Neuropsychiatric
- impaired cognition
- depression
- hyporeflexia
- Woltman sign
Name important factors when taking a history in a thyroid goiter patient
Age Duration Rapidity of growth Family history Personal history of RT
What is Berry sign?
Absence of distal carotid pulsation -> malignancy
What is Pemburton sign?
Bilateral arm elevation -> facial plethora
Indicates venous obstruction in goiter
Name lab findings in primary hyperthyroidism
TSH decrease
T3/4 increase
Name lab findings in secondary hyperthyroidism
TSH increase
T3/4 increase
Name lab findings in primary hypothyroidism
TSH increase
T3/4 decrease
Name lab findings in secondary hypothyroidism
TSH decrease
T3/4 decrease
Which thyroid diagnosis requires a radioisotope scan?
Primary hyperthyroidism
Name causes of increased uptake radioisotope scan
Grave’s
Autonomous nodule
Plummer’s disease
Name causes of normal uptake radioisotope scan
Thyroiditis
Drug-induced
Factitious
What kind of nodules can a radioisotope scan show?
Hot (hyperfunctioning)
Warm (iso-functioning)
Cold (non-functioning)
Which nodule has a risk of malignancy?
Cold nodule
Which serum test should be performed in suspected medullary thyroid cancer?
Serum calcitonin
Why should U/S be performed before biopsy?
To prevent distortion of the thyroid architecture
Which system is used to classify thyroid U/S findings?
TIRADS
Which system is used to report thyroid cytopathology?
Bethesda
Discuss the Bethesda system
- Unsatisfactory
- Benign
- Atypia/follicular lesion of undetermined significance
- Follicular neoplasm
- Suspicious for malignancy
- Malignancy
Name the 4 common types of thyroid cancer
Papillary
Follicular
Medullary
Anaplastic
Which is the most common thyroid cancer?
Papillary
How does papillary thyroid carcinoma spread?
Lymphatically
How does follicular thyroid carcinoma spread?
Haematogenously
What is medullary carcinoma associated with?
MEN syndrome type 2A and type 2B
What is the average survival time in anaplastic thyroid carcinoma?
3-6m
Name complications of thyroid surgery
Recurrent laryngeal nn injury
Ext br superior laryngeal nn injury
Hypoparathyroidism
Hemorrhage
Name indications for thyroid surgery
Compression symptoms
Cosmetic
Failed medical treatment
Large retrosternal goiter
Give 2 reasons for post-thyroidectomy thyroid hormone replacement therapy
- Prevents hypothyroidism
2. Suppresses microscopic malignancy
Name adjuvant treatments for thyroid carcinoma
Radioactive iodine ablation
Suppression therapy
Which adjuvant therapy is used in medullary thyroid carcinoma?
EBRT
Intensity modulated RT
How do you F/U medullary carcinoma?
TSH
Calcitonin
CEA
What is the epidemiology of thyroid goiter?
F>M
Decreases with age
What is the weight of a normal adult thyroid gland?
20-30g
What is the volume of a normal adult thyroid gland?
7-10ml
What is the location of the thyroid gland?
Caudal to larynx surrounding the anterolateral part of the trachea
How can goiters be differentiated?
- Morphology
- Thyroid function
- Dignity
How can goiters be classified according to morphology?
- Diffuse
2. Nodular
Name causes of a diffuse goiter
Grave’s
Hashimoto’s
Pituitary adenoma
Iodine deficiency
Name causes of a nodular goiter
Cysts
Adenoma
Cancer
How can goiters be classified according to thyroid function?
Nontoxic
Toxic
Hypothyroid
Name causes of a nontoxic thyroid goiter
Iodine deficiency
Name causes of a toxic thyroid goiter
Grave’s
Toxic multinodular
Name causes of a hypothyroid thyroid goiter
Hashimoto’s
Congenital hypothyroid
Name clinical features of thyroid goiter
Asymptomatic Hyperthyroid symptoms Hypothyroid symptoms Obstructive symptoms LN enlargement Berry sign Pemberton sign Carotid bruit and palpable thrill (Grave's)
How can you diagnose a thyroid goiter?
- Palpation
- Bloods (TSH, antibodies, calcitonin)
- Imaging (U/S, CT, MRI)
- FNA
How is goiter classified by palpation?
0 - not palpable or visible
1 - palpable but not visible
2 - palpable and clearly visible
Name causes of primary hypothyroidism
Hashimoto's thyroiditis Iatrogenic Anti-thyroid medication - amiodarone - lithium Thyroiditis - silent thyroiditis - subacute granulomatous thyroiditis - postpartum thyroiditis
Name causes of secondary hypothyroidism
Pituitary adenoma
Iatrogenic
Infiltrative disease
Name causes of tertiary hypothyroidism
Hypothalamic disorders
Name causes of euthyroid sick syndrome
Severe illness
Severe physical stress
Name causes of primary hyperthyroidism
Grave's disease Toxic MNG Toxic adenoma Postpartum thyroiditis De Quervain thyroiditis
Name causes of secondary hyperthyroidism
Thyrotropic adenoma
What genetic factors are medullary carcinomas associated with?
RET gene mutation (MEN 2)
Familial medullary carcinoma
What genetic factors are papillary carcinomas associated with?
RET/PTC rearrangement
BRAF mutation
What genetic factors are follicular carcinomas associated with?
PAX8-PPAR-gamma rearrangement
RAS mutation
What genetic factors are anaplastic carcinomas associated with?
TP53 mutation
Name red flags for thyroid cancer
Male sex Age <14 or >70 RT history Family history (MEN2, thyroid, Gardner syndrome) Rapid growth Firm, fixed nodule Cervical lymphadenopathy
Name histological findings in papillary thyroid cancer
Psammoma bodies
Orphan Annie eyes nuclei
Nuclear grooves
Name histological findings in follicular thyroid cancer
Uniform follicles
Vascular/capsular invasion
Name histological findings in medullary thyroid cancer
Ovoid cells of C cell origin Stromal amyloid (Congo red stain)
Name histological findings in anaplastic thyroid cancer
Undifferentiated giant cells
Name indications for total thyroidectomy
Well-differentiated carcinoma
Medullary carcinoma
Resectable anaplastic
Name contraindications for hemithyroidectomy
Intrathyroidal tumour >4cm
No extrathyroidal spread
No distant/nodal metastasis
No high-risk patient factors
