Differentiated thyroid cancer (covered mainly in other sets) Flashcards
What are the different histological types of thyroid cancer ?
- Papillary thyroid carcinoma (about 70%)
- Follicular thyroid carcinoma (about 15%)
- Poorly differentiated thyroid carcinoma (< 5%)
- Udifferentiated (anaplastic) thyroid cacinoma (< 5%)
- Medullary thyroid carcinoma (5-10%)
- others (lymphoproliferative neoplasias, metastases)
What do most differentiated thyroid cancers take up and secrete ? and what hormone drives them ?(hint think what drives normal thyroid function)
They take up iodine and secrete thyroglobulin
Driven by TSH
Do differentiated tumours indicate a better or worse prognosis than other solid tumours ?
A better prognosis
Differentiated thyroid cancers (DTC’s) are 2-3 times more common in females and less common in afro Americans ? T/F?
True
Exposure to what predisposes patients to DTC’s ?
Strong association with exposure to radiation
DTC’s have No association with diet, other proven malignancies, family history, smoking or other lifestyle factors, except from clusters associated with nuclear incidents . T/F?
True
What do the majority of DTC’s present with?
Palpable nodules
Approx 5% present with local (cervical lymphadenopathy) or disseminated metastases (usually presents as pathological fractures of long bones e.g. femur)
What is the commonest histo type of thyroid cancer ?
Papillary cancer
How does papillary thyroid cancer normally spread ?
- Tends to spread via lymphatics
- Can spread Haematogenously where it spreads to lungs, bone, liver and brain
What condition is papillary thyroid cancer linked with ?
Hashimoto’s thyroiditis
What is the second most common histological type of thyroid cancer and how does it usually spread ?
Follicular carcinoma
- Incidence slightly higher in regions of relative iodine deficiency
- Tend to spread haematogenously
- Lymphatic spread relatively rare.
What is the prognosis of papillary and follicular thyroid cancer ?
Very good, 10 year mortality < 5%
When suspecting thyroid cancer what is the main investigation used to diagnose it ?
Ultrasound guided fine needle aspiration (US FNA)
When suspecting thyroid cancer what should you do if there is vocal cord palsy suspected clinically ?
pre-operative laryngoscopy
What feautures point towards a potential thyroid cancer?
- New thyroid nodule age <20 or >50
- Male
- Nodule increasing in size
- lesion > 4cm in diameter
- History of head and neck irradiation
- Vocal cord palsy