thyroid last part (neoplasms) Flashcards
what are some clinical critieria you can use to see if a thyroid nodule is more likely neoplastic
solitary
in younger patients
in men
history of radiation to head and neck
funcitonal/hot nodules are more likely to be
benign
how can you definitively tell if a thyroid nodule is malignant or benign
FNA or surgical resection
a follicular adenoma is a solitary mass derived from?
follicular epithelium
does a follicular adenoma predispose you to follicular carcinoma?
NO
majority of follicular adenomas are?
nonfunctional
what are toxic adenomas
produce thyroid hormones independent of TSH stimulation **
toxic meaning autonomous meaning producing hormone
what is the mutation in toxic adenomas and toxic nodular goiters
somatic TSH receptor gain of function
gain of functio in the TSHR allow for _ from TSH
autonomy
toxic adenomas and toxic adenomas produce a _ thyroid nodule
HOT
describe what a thyroid adenoma looks like
solitary, encapsulated (well circumscribed)
bulges from the cut surface
and compressess adjacent thyroid
thyroid adenomas can be gray white to red brown dpending on
amount of colloid present (brown and glassy with colloid)
thyroid adenomas are well demarcated from adjacent normal thyroid tissue but can show what signs simular to a multinodular goiter
hemorrhage, fibrosis, calcification, cystic change
follicular adenomas are uniform follicles containing _
what cells are seen in thyroid adenomas
hallmark of thyroid adenomas
colloid
hurthle cells occasionally
well formed capsule seperating it from adjacent tissue (compresses normal tissue)
hurthle cells are seen in hasimotos with many germinal centers
follicular adenoma=
thyroid adenoma
adneomas present as a solitary _ (painless/painful) mass
nonfunctioning adenomas appear as _ nodules on radionucleotide scans
_ percent of cold nodules prove to be malignant
malignancy is rare in _ nodules (toxic adenomas)
definitive diagnosis by?
painless
cold
10%
hot
resctions (need to exclude capsular or vascular invasioni n carcinomas)
follicular adenomas do not _ and are an excellent prognosis
recur/metastsize
what are the different type of thyroid carcinomas
papillary
follicular
anaplastic
medullary
where are the thyroid carcinomas derived from
Follicular, Papillary, and Anaplastic are from follicular epithelium
medullary is from parafollicular C cells
what are the 3 precursor lesions for follicular carcinomas
papillary microcarcinoma –> PTC
noninvasive thyroid neoplasms –> follicular variant PTC
nonfunctioning follicular adenoma–> follicular carcinoma
what are the driver genes for follicular neoplasms
gain of function mutations RAS, PAX8- PPARG
conventional PTCs drivier mutations
RET, NTRK, BRAF
poorly differentiated/anaplastic driver mutations
TP53
medullary thyroid carcinoma driver mutation
RET
what are the major risk factors for thyroid carcinoma
ionizing radiation (papillary carcinoma/chernobyl disaster)
def dietary iodine (follicular)
what are the variants of papillary carcinoma
invasive follicular variant of PTC and noninvasive follicular thyroid neoplasm with papillary like nuclear features
follicular
tall cell
diffuse sclerosing
papillar microcarcinoma
what are the common variants of papillary carcinoma
coventional PTC
invasive encapsulated follicular variant of PTC
papillary carcinoma is associated with _ exposure
ionizing radiation exposure
what is the first sign of papillary carcinoma
cervical lymph node mass
how does papillary carcinoma of the thyroid present
freely movable, can have metastases to the lung, not distinguishable from a benign nodule
causes mass effects (dyspnea would be advanced disease)
papilallary carcinoma is a _ mass and you need _ to diagnose
it has _ prognosis and is dependent on _ and _ extension
cold
FNA
good
age and extrathyroidal extension
patients with papillary _ and nonivasive _ thyroid neoplas do good with a lobectomy alone. Total thyroidectomy can cause _ _ _ and iatrogenic _
microcarcinoma
follicular
vocal cord palsy
hypoparathyroidism
PTC morphology
foci of lymphatic invasion**
cervical node
cystic/fibrosis/calcifications
branching papillae with fibrovascular core**
psomomas bodies**
ground glass/coffee bean nuclei
what are ground glass nuclei
intranuclear grooves from invaginations of cytoplasm
what does the follicular variant of PTC look like
mutation?
coffee bean nuclei (ground glass) no papillae, all follicles
RAS mutation
tall cell papillary carcinoma variant looks?
mutations
tall columnar cells
eosionophilic cytoplasma
aggressive (increased invasion and mets)
BRAF RET/PTC
diffuse sclerosing variant of PTC
younger patients
distnant metz
papillary pattern, solid aread
lymphocytic infiltrate
LN metz
diffuse sclerosing PTC variant simulates?
hasimotos
papillary microcarcinoma variant
very small less than 1cm, identical to PTC and is an accidental finding
follicular carcinomas are _ nodules caused by?
most of them are _ (cold/hot)
painless
caused by idodine def
cold
follicular carcinomas are low risk and invade the _
they infiltrate the _
and there can be hematogenous spread
lymphatics
tissues
prognosis of follicular carcinoma depends on
invasion and stage at presentation
widely invasive
treatment of follicular carcinoma
total thyrodectomy and radioactive iodine
thyroid hormone to suppress residual carcinoma from responding to TSH
monitor thyroglobulin for recurrence
histology of follicular carcinoma
penetrate capsule and infiltrative neck
goes into capsules and vessels
can have central fibrosis and calcifications
poorly differentiated /anaplastic carcinomas are _ (benign/aggressive)
1/4 of them come from a _ _ carcinoma
aggressive
well differentiated
anaplastic carcinoma presents as a ?
rapidly enlarging mass
in anaplastic carcinoma there is often metastasis to the _ at the time of presentation
lungs
symptoms of anaplastic carcinoma
compression; dsypnea, dysphagia, hoarsness
treatment for anaplastic carcinoma
poorly differentiated
anaplastic: none, death
poorly diff: radical surgery/radioactive iodine
histology of anaplastic carcinoma
variable: giant cells, pleomorphic, spindle cells just depends
histology of poorly differentiated carcinoma
varies; necorsis, trabecular growth pattern, insular gorwth patterns
epithelial markers for anaplastic and poorly differentiated carcinoma
cytokeratin
what marker is negative in anaplastic and poorly differentiated carcinoma
thyroglobulin (thyroid differentiation marker)
medullary carcinomais a _ neoplasm and is derived from?
neuroendocrine
parafollicular cells (c cells)
medullary carcinoma is derived from C cells that secrete _ but _ is not a prominent feature
calcitonin
hypocalcemia
medulalry carcinoma is a _ syndrome and will secrete
paraneoplastic
serotonin, ACTH, VIP
most medullary carcinoma are sporadic caused by?
MEN 2A or MEN2B
FMTC (familial medullary thyroid carcinoma)
MEN syndome has a point mutation in?
RET
which one is more aggressive MEn2A or MEN2B
2B
all MEN2 patients with RET 2 are offered a prohylactic
thyroidectomy
sporadic medullary carcinoma presentation
solitary mass
paraneoplastic syndrome
calcitonin and CEA biomarkers
biomarkers for sporadic medullary carcinoma
calcitonin and CEA
familial medullary carcinoma (FMTC) presentation
bilateral and multicentric
familial meduallry thyroid carcinoma findings
RET and C cell hyperplasia
morphology of medullary carcinoma
calcitonin on IHC
multicentric c-cell hyperplasia
amyloid deposits
cluster of c cells
polygonal/spindle cells
amyloid in medullary carcinoma will show _ on congo red stain
apple green birefrengence
what are the congenital anomolies of the thyroid
thyroglossal duct or cyst
midline and anterior (superimposed infection can give an abcess and rarely give rise to cancer)
can happen at any age.
stratified squamous epi
