Goitre and nodules

Question 1

Who does it affect?

Answer 1

W>M

Question 2

What causes it?

Answer 2

Diffuse:

• Physiological (puberty or pregnancy).
• Autoimmune (Graves or Hashimotos).
• Acute viral thyroiditis (de Quervains thyroiditis).
• Iodine deficiency (endemic goitre), dyshormonogenesis. - Goitrogens, e.g. sulphonylureas.

Nodular: Multinodular goitre. Solitary nodule. Fibrotic (Riedell’s thyroiditis). Cysts.
Tumours: Adenoma, carcinoma, lymphoma

Miscellaneous:

• Sarcoidosis
• TB.

Characteristics of thyroid cancer:

• Papillary (70%), young people, spreads locally, good prognosis
• Follicular (20%), middle age, spreads to the lung/bone. Prognosis usually good
• Medullary cell (5%), often familial (MEN1), spreads locally and via mets. Poor prognosis
• Anaplastic <5%, aggressive, spreads locally, very poor prognosis

Question 3

How does it present?

Answer 3

A goitre is usually noticed as a cosmetic defect, although discomfort and pain in the neck can occur, and occasionally tracheal or oesophageal compression produces difficulty in breathing and dysphagia. The gland may be diffusely enlarged, multinodular or possess a solitary nodule. A bruit may be present and associated lymphadenopathy suggests that the goitre may be malignant

Question 4

Signs on examination?

Answer 4

Apart from the type of goitre then other signs would be dependent on what is the cause of the goitre.

Question 5

Investigations

Answer 5

Blood tests: Thyroid function tests

Imaging: High resolution thyroid ultrasound can delineate nodules and determine whether they are cystic or solid. Both types of nodule are usually benign, but can be malignant, and thus require FNA under ultrasound control. Chest and thoracic inlet x-ray to detect tracheal compression and large retrosternal extensions, are performed in patients with very large goitre or clinical symptoms (difficulty breathing).

FNA: for cytology should be performed for solitary nodules or a dominant nodule in a multinodular goitre because there is a 5% chance of malignancy.

Thyroid scan (using radioactive iodine): distinguishes between a functioning (rarely malignant) or non-functioning (10% malignant) nodule, but FNA has largely replaced this.

Question 6

Treatment

Answer 6

Usually not required, apart from introducing euthyroidism if necessary. Surgical intervention is required for the cosmetic effects of large goitres, pressure effects on the trachea or oesophagus, or confirmed or possible malignancy.

Question 7

Conditions that would present similarly

Answer 7

Normal anatomy
skin infections
lymphadenopathy
benign tumours
malignant primary tumours
salivary gland lumps
congenital and developmental lumps (thyroglossal cyst, brachial cyst, laryngocele, dermatoid cyst, lymphangioma, haemangioma)
Carotid body tumours and aneurysms
Trauma.