Thyroid Flashcards
MC thyroid malignancy (over 80% of Ca)
Papillary Thyroid Carcinoma
PTC MC arises as a
Single nodule
Least aggressive form of thyroid CA
Papillary thyroid cancer
- slow growing and often remains confined to thyroid and regional lymph nodes
Majority of thyroid nodules remain
Microscopic and benign; indolent
Unless >1cm diameter
Associated w/ hurthle cell
Follicular thyroid carcinoma
Most aggressive thyroid cancer
Aplastic thyroid carcinoma
Treatment of choice for actual thyroid carcinoma
Surgical thyroidectomy or removal
- can be hemi-lobectomy or total lobectomy based on type and size of tumor
First line screening for thyroid carcinoma
Ultrasound
Pregnant women can have thyroid surgery after ________ weeks of gestation
24
Functional unit of a thyroid
Follicle
Follicle contains
Colloid w/ thyroglobulin
Thyroid is the main site for this
Iodine oxidation via perioxidase
Test for thyroid function
TSH (0.4-4.0 mU/L)
TRH axis
TRH—>TSH—>T3/T4
Overstimulation of TRH via hypothalamus leads to growth and hyperplasia of thyroid gland (increase in number and size of follicles= gland growth)
Goiters can be:
Linked with?
- euthyroid, hypothyroid, and hyperthyroid
- iron deficiency
Thyroid hormone in circulation?
MC as T4 (inactivated)
10% T3 (active form)
Primary Hypothyroidism clinical image
increased TSH and decreased FT4
Secondary hypothyroidism clinical picture
decreased TSH and decreased FT4
Etiologies of hypothyroidism
1- hashimotos 2- de quervain 3- cancer 4- chemo agents 5- amiodarone
S/S of hypothyroidism
Weight gain Low energy Brittle nails and hair Bradycardia Untreated can lead to miscarriage and pregnancy problems
Explain the patho of hashimotos
Autoimmune destruction of follicular cell (destruction of thyroglobulin, thyroid peroxidase and TSH receptor)
- hyperthyroidism initially—> hypothyroidism
