Thyroid Nodules Flashcards
What percentage of women suffer from solitary thyroid nodules?
5%
Of the women who suffer from solitary thyroid nodules, what percentage suffer from malignant thyroid nodules?
5%
Which types of solitary thyroid nodules are benign?
- Thyroid cysts
- Colloid nodules
- Benign follicular adenoma
- Hyperplastic nodules
Which types of malignant thyroid nodules are malignant?
- Papillary thyroid carcinoma
- Follicular thyroid carcinoma
- Medullary thyroid carcinoma
- Lymphoma
- Poorly differentiated
What percentage of malignant solitary thyroid nodules are papillary thyroid carcinomas?
80%
Follicular thyroid carcinoma are cancers of which cells?
Parafollicular C cells
How are follicular thyroid carcinomas spread?
Haematogenous spread
How can it be confirmed that a thyroid nodule is within the thyroid?
If it moves on swallowing it is invested in pretracheal fascia
What are 2 essential questions to ask in a history for a solitary thyroid nodule?
- Previous neck of irradiation
- Family history of thyroid cancer
What are two keys things to look for on examination for a solitary thyroid nodule?
- Neck nodes
- Hoarseness (and bovine cough)
Why are neck nodes a major worry if found in the context of a solitary thyroid nodule?
Lymph node spread of a papillary thyroid carcinoma
Why is hoarseness and a bovine cough a worry if found on examination in the context of a solitary thyroid nodule?
Recurrent laryngeal nerve palsy may indicate an aggressive thyroid cancer
What is a bovine cough?
A wheezing type cough caused due to inability to close the rima glottidis
Which three investigations would be undertaken primarily if there is a solitary thyroid nodule?
- TSH
- USS
- FNA
Why may a core biopsy be superior to a FNA of a solitary thyroid nodule?
It gives more idea about morphology and structure
If TSH is elevated when testing for a solitary thyroid nodule, what may this suggest?
Hypothyroidism
Autoimmune thyroiditis
If TSH levels are suppressed when testing a solitary thyroid nodule, what may be the cause an which inestigation would then be a good idea?
Solitary toxic adenoma
Isotope scan
(the tumour does not take up the isotope, but the rest of the gland does)
What is the normal range for TSH?
0.4 - 4mU/L
What constitutes a low risk patient with a differentiated thyroid cancer?
Age < 50
Tumour < 4cm
What is the treatment for a low risk patient with a differentiated thyroid cancer?
Lobectomy
What is the treatment for a high risk patient with a differentiated thyroid cancer?
Total thyroidectomy
What levels is the central neck?
L6/7
What levels is the lateral neck?
L2-L5
To which level in the neck do most thyroid cancers spread?
L3/4
(lateral neck dissection required)
Why is it recommended to keep TSH levels < 1 mU/L in the presence of a differentiated thyroid carcinoma?
TSH stimulates follicular cells which may worsen the tumour
What percentage of malignant thyroid cancers do follicular thyroid cancers comprise?
10%
The diagnosis of a follicular thyroid cancer depends on if it has invaded the capsule or had vascular invasion. What is the tumour called before this stage?
Benign follicular adenoma
What is the most common type of follicular thyroid cancer?
Minimally invasive thyroid follicular carcinoma
Due to the haematogenous spread of follicular thyroid carcinoma, what are the two most common places for metastases?
- Bone
- Liver
What are the treatment options for minimally invasive thyroid follicular carcinoma?
Thyroid lobectomy
Total thyroidectomy (if significant vascular invasion)
A thyroid lymphoma often develops on a background of which condition?
Autoimmune hypothyroidism
Was is the onset like for a thyroid lymphoma?
Rapid
Which type of people are likely to be affected by thyroid lymphoma?
Females 70-80
What are the treatment options for thyroid lymphoma?
- Chemotherapy
- Radiotherapy
- Steroids (for the acutely unwell)
What is secreted by a medullary thyroid carcinoma?
Calcitonin
(this can be used as a tumour cell marker)
How can meduallary thyroid carcinoma be diagnosed?
Fine needle aspiration
What are the 4 types of medullary thyroid carcinoma?
- Sporadic
- Familial non-MEN
- Familial MEN
- Familial MEN2a and b
If a child is suspected to have familial MEN what treatment may be considered?
Prophylactic thyroidectomy
What is MEN?
Multiple endocrine neoplasia
(Wermer syndrome)
MEN2a is a condition which is associated with which other conditions?
- Phaeochromocytoma
- Medullary thyroid carcinoma
- Hyperparathyroidism
What is phaeochromocytoma?
A tumour of the adrenal gland which causes too much adrenaline/noradrenaline release
MEN1 commonly affects which endocrine glands?
- Pituitary
- Parathyroid
- Pancreas
The 3 Ps
How can the function of the thyroid in multinodular goitre tested and what is the expected result?
TSH
Potentially slightly supressed
What are the treatment options for multinodular goitre?
- Leave alone
- Radioactive iodine (significant hyperthyroidism)
- Surgery (structural issues)