Thyroid Flashcards
If FNAC suggests follicular cells what must be done?
Hemithyroidectomy to distinguish histopathalogically between adenoma and carcinoma
Is it possible to distinguish follicular adenoma from carcinoma on cytological grounds?
No
Treatment for follicular carcinoma?
Completion thyroidectomy and post operative radio ablation
Where does follicular carcinoma metastasise to?
Bone via blood stream
Where does papillary carcinoma commonly metastasise to?
Cervical LN
What is thyroxine bound to?
- Thyroid binding globulin 99.98%
What is the most common thyroid cancer?
Papillary thyroid cancer 70%
What is the drug of choice during pregnancy for Graves’ disease ?
Propothyouracil - as it less readily crosses the placenta
What type of goitre does Graves’ disease produce?
Diffuse
What is the mean age of presentation of follicular carcinoma?
50 (usually as a solitary thyroid lump)
What % of medullary thyroid cancer is familial?
20%
What does MTC arise from?
Para follicular c cells which are neural ectodermal in origin
Treatment of MTC?
Total thyroidectomy with bilateral LN clearance
What hormones does MTC produce?
- Calcitonin
- Prostaglandins
- 5 HT (hydroxytryptamine) - serotonin
- ACTH
Features of malignancy in a thyroid nodule?
- Hard fixed mass
- Elevated serum calcitonin levels
- History of neck irradiation
- Nerve palsy
What percentage of cold nodules are malignant in adults?
10-20%
50% in children
What thyroid cancers does FNA have a high pick up rate for?
- Medullary carcinoma
- Anaplastic carcinoma
- Papillary carcinoma
- Hashimoto’s thyroiditis
Adjuvant treatments for papillary thyroid cancer?
- Radio iodine therapy
2. Thyroid hormone suppression
What % of thyroxine is bound in plasma?
99.89%
What is thyroxine bound to?
Thyroid binding globulin
What is Berrys sign?
Absence of carotid pulse due to malignant thyromegaly
Anaplastic carcinoma
Poor prognosis
Older patients
Men1
- Parathyroid hyperplasia
- ZES
- Insulinoma
- Ppoma (pancreatic polypeptide)
- Pituitary adenoma (prolactinoma, ACTHoma)
- Thyroid adenoma
- Adrenal adenoma
- Foregut or midgut carcinoid
- Lipoma
MEN2a
- Parathyroid hyperplasia
- Phaeochromocytoma
- MTC
