Thyroid Path- Krafts Flashcards
Low TSH
Low T4
Secondary Hypothyroidism
High TSH
Low T4
Primary Hypothyroidism
Low TSH
High T4
Primary Hyperthyroidism
High TST
High T4
Secondary (or tertiary) hyperthyroidism
A little variation in T4 can cause a ______ fluctuation in TSH
LARGE
What are the 3 anti-thyroid antibodies you should check for?
Anti-peroxidase (anti-microsomal)
Anti-thyrogolobulin
Anti-TSH-receptor
What are you looking for when doing the radioiodine thryoid scanning?
Looking at iodine uptake
A lot of uptake = hot
Less active = cold (10% malignant)
Arrhythmias Tremor Lid Lag & wide staring gaze Warm, moist, flushed skin Diarrhea
Suggests……
HYPERthyroidism
Delayed reflexes Myxedema Slow pulse Constipation Dry, pale skin
Suggests….
HYPOthyroidism
What is cretinism?
Congenital Hypothyroidism
Which auto-antibody is most specific for Hashimotos?
Anti-peroxidase
Why is there transient hyperthyroidism in Hashimotos?
As follicles are destroyed some colloid leaks out
45 year old female:
Non-painful enlarged thyroid
Weight gain
Hyporeflexive
Lab Tests:
+ anti-peroxidase
+anti-TSH-receptor
FNA:
Hurthle Cells
Many germinal centers
Hashimotos
What thyroiditis is associated with a recent viral upper respiratory infection?
DeQuervain Thyroiditis (aka subacute or granulomatous)
30 year old male
Flu-like syptoms
Throat pain radiating to ear
Enlarged thyroid
DeQuervain Thyroiditis
*usually self-limiting, no need to treat!
In which thyroiditis would you see multinucleate giant cells?
DeQuervain Thyroiditis (aka granulomatous thryoiditis!!)
3 months after pregnancy
Enlarged painless thyroid
Otherwise asymptomatic
Histology:
Lymphocytes but no germinal centers, plasma cells, or Hurthle cells
Silent Thyroiditis
Rock-hard, “woody” neck mass?
Reidel’s Thyroiditis
What is Reidel’s Thyroiditis?
Fibroblast proliferate and lay down collagen
Patients may have other glands involved
Hypothyroidism
What is myxedema?
Accumulation of hydrophilic ground substance (glycosaminoglycans) through the connective tissues in the body
Leads to: non-pitting edema Coarsening of facial features Enlargement of tongue Deepening of voice
Do you myxedema with hyper or hypo-thyroidism?
Hypothyroidism!
What is Grave’s disease?
Autoimmune
Ab stimulates TSH receptor
What is the triad for Grave’s Disease?
- Hyperthyroidism
- Opthalmopathy (lid lag + exopthalmos)
- Dermopathy (pretibial myxedema)
On histology if you saw crowed follicular epithelial cells form that form papillae and scalloped borders, what would you think?
Grave’s Disease
What would you use to treat grave’s disease?
B-blocker for symptoms
Propylthiouracil to decrease thyroid hormone synthesis
Describe the process of goiter developmenet
Thyroid makes less thyroid hormone
TSH level goes up
Thyroid grows bigger
What is the first stage of goiter formation?
Simple goiter = diffuse nontoxic goiter, colloid goiter
Do simple goiter’s have nodules?
NO!
Describe a multinodular goiter
Second stage - developes pre existing goiter
Thyroid is huge and nodular
What causes a goiter?
Excessive TSH stimulation
Can be due to
- lack of iodine
- ingestion of substance that interfere with thyroid hormone synthesis
- Hereditary enzyme defects
**can be hyper, hypo, or euthyroid
What is Jod-Basedow Phenomenon?
When a patient has a goiter (due to idodide deficiency)
A small amount of iodide is given to the patient (maybe for imaging)
But thryoid is under HEAVY TSH hormone stimulation
Acute hyperthyroidism and even hyperthyroid crisis can occur - thyrotoxicosis
How should you biopsy the thyroid?
Fine Needle Aspiration
Follicular Adenoma
Benign proliferation of follicules surrounded by a fibrious capsule
Why should you also surgically remove a follicular adenoma even though it is benign?
Hard to distinguish from Follicular adenocarcinoma = malignant
Most common thyroid malignancy?
Papillary Carcinoma
Orphan Annie Eye Nuclei
Papillary Carcinoma
Empty-appearing nuclei w/ central clearing
Nuclear Grooves
Papillary Carcinoma
Line/Groove with in the nucleus
Psammoma Bodies
Papillary Carcinoma
Concentric circular calcification
Follicular Carcinoma
Malignant proliferation of follicles
How would one distinguish histologically a follicular adenoma from follicular carcinoma?
Signs of malignancy:
- Vascular Invasion
- Tumor cells invade through capsule
Can you distinguish follicular adenoma from carcinoma from FNA biopsy?
No!!!!
Would need to see whole specimen
How does follicular carcinoma like to spread?
Hematogenously
Different, because normally carcinoma’s like to spread through lymph nodes
Medullary Carcinoma
Malignant proliferation of parafollicular C Cells
What type of tumor is a medullary Carcinoma?
Endocrine Tumor! Secrete Calcitonin (may lead to hypocalcemia)
(Papillary and Follicular are epithelial tumors)
In a medullary tumor calcitonin often deposits with in tumor as ______
Amyloid!
What would a FNA of medullary carcinoma look like?
Malignant cells in an amyloid stroma
Which MEN syndromes is medullary carcinoma associated with? What is the genetic mutation?
MEN 2A & 2B
Mutation in RET gene
Anaplastic Carcinoma
Undifferentiated malignant tumor of thyroid
Usually seen in elderly
Invades local structures leading to dysphagia or respiratory compromise
POOR PROGNOSIS
