CIS/DSA Thyroid nodules/surgery (Tieman) Flashcards
nodules are more common in what sex
women x4
BUT they are more often malignant in men
what age is risky for nodules
malignant nodules more common in ages 60
what in the history is significant in terms of work up for thyroid nodules
gender
-more common to find nodules in women but more common to have malignant nodules in men
age
history of radiation exposure to head and neck
family history of thyroid cancer, FAP, MEN, multiple hamartoma syndrome
Voice symptoms
Visual symptoms
fatigue, anxiety
what labs do you order in work up of thyroid nodules
TSH
T4
T3
when is FNA indicated (Fine needle aspiration) in work up of thyroid nodules
> 1cm and/or suspicious on US (hypoechoic, irregular, intranodular, vascularity, calcifications, nodal mets)
May need to aspirate multiple nodules, if more
than one meets criteria (up to 4 nodules
90% sensitivity and specificity
what if FNA is benign in thyroid nodule work up
requires 6-12 month follow up
5% false negative rate
what happens if you find an indterminant result on FNA of thyroid nodule
Usually contains follicular cells or Hurthle cells
” Formerly required surgery to examine entire nodule
◦ Malignancy in follicular lesions determined by invasion of capsule
or follicular cells in surrounding blood vessels or lymphatics
” Now can be further evaluated by gene-expression
classifier profile with 90-95% sensitivity and specificity
FNA showing orphan annie cells
psammoma bodies
intra-nuclear grooving
papillary projectings
papillary carcinoma of thyroid
what are the low risk factors with papillary carcinoma
<2 cm
well differentiated
what is the long-term survival of papillary carcinoma of thyroid
ranges from 50-99%
◦ Survival rates depend on prognostic factors
what are the high risk factors associated with papillary carcinoma of thyroid
> 40 years old
male
capsular invasion, extrathyroidal extension
distant mets
> 4 cm
poorly differentiated
stippled cytoplasm
sheets of cells
follicular lesion of thyroid
extensive amyloid deposits in the cellular matrix
hurthle cells
what two things define the indeterminate FNA
hurthle cells
follicular lesion
when you have an FNA that is indeterminate, what is done first after this finding>
gene expression classifier method to determine likelihood of malignancy
large bi lobed nuclei with intense staining
parafollicular c cells
medullary carcinoma
what are medullary carcinomas of the thyroid derived from….
what do they secrete?
what percentage are sporadic and what percentage are familial ?
what is the gene involved ?
◦ Parafollicular “C” cells which secrete calcitonin
◦ 5-10% of thyroid cancers, PTC and FTC ~90%
◦ Sporadic (75%) Usually more indolent
◦ Familial (25%)—MEN 2A (60%),2B (5%) or Familial
(35%)
” Screen for parathyroid and adrenal disease if 2B
suspected
” Pre-operative calcitonin levels
“ RET proto-oncogene in patient and relatives
what is the treatment of medullary carcinoma and what is the follow up
◦ Total thyroidectomy +/- lymph node dissection
Radioactive iodine and serum thyroglobulin of no use in follow-up
- Medullary cancers followed with serum calcitonin levels
and family evaluation
very aggressive, rapidly enlarging painful mass with obstructive symptoms
can be diagnosed with FNA
anaplastic thyroid carcinoma - 1% of thyroid cancers
what is the treatment of anaplastic thyroid carcinoma
Palliative care only, doesn’t respond well to
surgery, radiation therapy, or
chemotherapy
what is the follow up for well -differentiated epithelial thyroid cancer (post-op)
- Most well-differentiated epithelial thyroid
cancer treated with post-op radioactive
iodine to ablate subclinical disease or
mets
! Thyroid replacement
! Monitor physical exam and thyroglobulin
levels to look for recurrent disease
! Use of PET scan promising but not yet standard of care
in what cases is surgery appropriate in hyperthyroidism
Hot nodule
toxic nodular goiter
grave’s disease - especially pregnant pt
multinodular goiter
what is the concern with a rapidly growing goiter
carcinoma
what are the complications that might occur with thyroidectomy
recurrent laryngeal n injury superior laryngeal n. injury hypoparathyroidism hypothyroidism extensive blood loss rare infection
are multiple nodules or firm solitary nodules more risky?
multiple nodules or diffuse nodularity –> benign
firm solitary nodule —> particularly in older men is more suggestive of malignancy
what does low serum TSH in a thyroid nodule mean?
lower liklihood of malignancy
ultrasound findings in a nodule that are considered suspicious for malignancy include what?
microcalcifications
hypervascularity
infiltrative margins
being hypoechoic compared with surrounding parenchyma
having a shape that is taller than its width on transverse view
is malignancy more common in cold or hot nodules
more common in cold nodules
what do the presence of colloid and macrophages in aspirate (FNA) suggest
benign lesion
what factors confirm the diagnosis of follicular carcinoma
permanent section pathology
what factors confirm the diagnosis of medullary carcinoma
surgery
FNA
calcitonin level
RET oncogene
what factors are associated with a worse prognosis in medullary carcinoma
MEN2B and sporadic
what is the next step in a pt with a thyroid nodule and normal thyroid function tests
ultrasound
cystic are more likely benign
what is the most common genetic alteration in Papillary thyroid cancer
PTC-RET proto-oncogene
most common thyroid neoplasm
papillary carcinoma
young female pt’s
childhood radiation exposure
peak age is b/w ages 30-50
-calcified clumps of cells (psammoma bodies)
what is the most important prognostic factor in well-differentiated thyroid cancer
age at diagnosis
what is the primary treatment of differentiated thyroid cancer
surgical ablation
peak incidence b/w 40-60 more common in women more common in iodine deficient areas can spread hematogenously can spread to liver, bone, lung (mets)
follicular carcinoma
painless thyroid mass
80% 10 year survival in 40-60 yr olds
diagnosis requires demonstrations of cellular invasion of capsule or vascular or lymphatic channels - can’t be determined with FNA
what is the very first step in working up the thyroid nodule
serum TSH
after you have done the TSH as the first step in workup of thyroid nodule, what do you do …. normal TSH? low TSH?
Normal- thyroid Ultrasound
Low TSH- radioisotope scan
lets say you have low TSH (high T3 and T4) and you have a hot nodule after you perform a radioisotope scan….
surgery or radioablate with iodine
what is the next step in workup of a nodule AFTER you have done TSH and it is normal….
do an ultrasound
if the pt is euthyroid you don’t scan them and you now the nodule is going to be cold
what does an ultrasound of a nodule tell us
cystic or solid
what if you found a solid nodule on Ultrasound (after you found normal thyroid studies)
what is the next step
FNA
if the FNA is benign then the next step in management is to follow the patient b.c there is a 5% chance of having false negative
if they come back in 6 months for follow up, what might prompt you to get another FNA?
- symptomatic
- gets bigger- hard and fixed
if a pt has MEN IIA syndrome , what do you need to do before surgery
urinary VMA’s and metenephrines to screen for pheochromocytoma
what is the treatment for medullary carcinoma
total thyroidectomy PLUS all the lymph nodes
must do lymph dissection b/c chemo doesn’t work/ radiation doesn’t work
the only shot at survival is surgery
pt has pre-clinical MEN 2A b/c he tested positive for RET proto-oncogene . what should be done next ?
prophylactic thyroidectomy
are papillary carcinomas more likely multifocal or unifocal and how does this play into treatment ?
multifocal
there are usually a lot of nodules that you can’t see or feel
for treatment of papillary carcinoma you will want to do a total thyroidectomy AND take out the lymph nodes b/c it spreads through the lymph nodes
what do you do after you have performed a total thyroidectomy for papillary carcinoma and you have also taken the lymph nodes out…
radioactive iodine to prevent mets- small subclinical mets
also check thyroglobulin ! if it starts increasing in the serum then you know you probably have mets
lets say you did thyroid function tests and they were normal
then you did ultrasound and you found solid nodule
then you did FNA and found follicular lesion
how do you know if it is benign or malignant ?
and what if the lesion is malignant ?
the FNA can’t tell you benign or malignant you must see invasion of the capsule or malignant cells in the surrounding blood vessels
in the old days you had to go to surgery but now you can just do gene-expression classifier profile - genetic test that tells you if this is a worrisome nodule or not
if it is malignant –> it is typically unifocal and you want to do a total thyroidectomy b/c you are going to treat them post-operatively wtih radioactive iodine so just take the whole lobe anyways to increase effectiveness of the iodine
also don’t have to take lymph nodes b/c it spreads hematogenously
