Download Thyroid Carcinoma

Thyroid Carcinoma
Vic V. Vernenkar, D.O.
St. Barnabas Hospital
Department of Surgery
Introduction
 Infrequent cancer -1% of all cancers
 Benign diseases common
 1200 pts die annually
 Requires multidisciplinary approach
Anatomy
Frequency
 17,000 cases diagnosed annually.
 Women 3 times more than men.
 Peak incidence 30-40s.
 Papillary, follicular, medullary, anaplastic,
lymphoma, and sarcoma.
 Papillary 80%, follicular 10%, medullary 510%, anaplastic 1-2%.
Etiology/Risk Factors
 Arise from the two cell types in the gland.
 Follicular cells make papillary, follicular,
and anaplastic.
 C-cells produce medullary.
 Radiation exposure (papillary).
 Populations with low dietary iodine have a
higher proportion of follicular and
anaplastic cancers.
History
 Painless, palpable solitary nodule.
 Nodules are present in 4-7% of population.
 Most are benign
 5% are malignant
 Age at presentation (>60 and <30)
 Sex (males)
 Rapid growth
History
 Malignant nodules usually painless
 Sudden onset pain usually benign.
 Hoarseness suggests malignancy, nerve
involvement.
 Dysphagia
 Heat intolerance, palpitations suggest
autonomously functioning nodules.
 Family history (medullary).
Physical Exam
 Thorough HEENT exam includes:
 Thyroid gland
 Soft tissues of neck
 Solid, soft, mobile, or fixed?
 Tenderness?
 Laryngoscopy if hoarse preop!
The Goal…..
 Differentiate malignant from benign.
 Determine which patients require
intervention.
 Who can be monitored?
 Avoid unnecessary surgery.
Fine Needle Aspiration
 First intervention in evaluation of a nodule.
 Inexpensive, easy, few complications.
 Need a good cytopathologist.
 Four types of results; Benign,
malignant,indeterminate, non-diagnostic.
 69% benign, 4% malignant, 10% indeterminate,
17% non-diagnostic.
 Sensitivity 83%, specificity 92%
 False positive 2.9%, negative 5.2%
FNA
 If non-diagnostic, repeat
 If malignant go to OR
 If benign, stop and follow
 If indeterminate or suspicious OR
 OK, the path says it’s a “Follicular neoplasm.”
 FNA can diagnose papillary and medullary
cancers
 Complications of FNA
Laboratory
 TSH sensitive for hypo and
hyperthyroidism, but does not rule out
malignancy.
 TFTs not indicated in work up initially.
 Serum thyroglobulin used as tumor marker
post op.
 Calcitonin, for post op monitoring in
Medullary cancers.
Imaging
 Ultrasound: solid vs. Cystic, for FNA accuracy,
for monitoring of benign lesions.
 Scans: determines function of the nodule. Cold
nodules are those that don’t take up iodine123, hot
ones are the opposite.
 Carcinoma cannot be ruled out based on scans,
with 4% of hot nodules being malignant. May be
useful with indeterminate however.
 CT and MRI not used routinely.
Papillary Carcinoma
 Most common (80%)
 Women 3 times more common
 30-40 years of age
 Familial also (FAP)
 Radiation exposure as a child
 Patients with Hashimoto’s thyroiditis
 Slow growing, TSH sensitive, take up iodine, TSH
stimulation produces thryroglobulin response.
Papillary Carcinoma
 Pathology:Unencapsulated, arborizing
papillae. Well differentiated, rare mitoses.
 50% have psammoma bodies (calcific
concretions, circular laminations.
 Multicentric with tumor present in
contralateral lobe as well.
Papillary Carcinoma
 Local invasion through capsule, invading
trachea, nerve, causing dyspnea, hoarseness.
 Propensity to spread to the cervical lymph
nodes. Clinically evident in 1/3 patients.
Most commonly central compartment,
located medial to carotids, from hyoid to
sternal notch.
 Distant spread to bone, lungs.
Follicular Carcinoma
 Second most common (10%)
 Iodine deficient areas
 3 times more in women
 Present more advanced in stage than
papillary
 Late 40’s
 Also TSH sensitive, takes up iodine,
produces thryroglobulin.
Follicular Carcinoma
 Pathology: round, encapsulated, cystic
changes, fibrosis, hemorrhages.
Microscopically, neoplastic follicular cells.
 Differentiated from follicular adenomas by
the presence of capsule invasion,vascular
invasion.
 Cannot reliably diagnose based on FNA.
Follicular Carcinoma
 Local invasion is similar to papillary cancer
with the same presentation.
 Cervical metastases are uncommon.
 Distant metastases is significantly higher
(20%), with lung and bone most common
sites.
Treatment and Prognosis
 Controversy regarding extent of therapy
continues.
 Surgical excision whenever possible.
 Total thyroidectomy has been mainstay (all
apparent thyroid tissue removed).
Complications include nerve damage
bilaterally, parathyroid injury bilaterally.
 After, get radioiodine scan, ablation if
residual disease or recurrence.
Treatment and Prognosis
 Over the years, modification to procedure to
reduce the above complications.
 Subtotal thyroidectomy( small portion of
thyroid tissue opposite the side of
malignancy is left in place) and postop
ablation.
 Thyroid lobectomy and isthmectomy also
a viable option with small tumors
Neck
 Examine the neck prior to surgery to detect
lymph node spread.
 Gross cervical mets should be removed en
bloc with a dissection in the compartment in
which they reside.
 Excision of single nodes is not adequate.
 Elective lymph node dissection is not done,
as radioactive iodine takes care of this.
Postoperative Radioiodine and
Ablation
 Radioiodine targets residual thyroid tissue
and tumor after thyroidectomy.
 Given in diagnostic doses and therapeutic
doses to ablate tissue.
Thyroid Suppression Therapy
 Maintained on thyroxine after surgery and
ablation. Low TSH levels reduce tumor
growth rates and reduce recurrence rates.
 Most recommend TSH levels of 0.1 mU/l.
 Follow-up q 6 months with thyroglobulin
levels and repeat scans.
 Thyroglobulin is good because well
differentiated tumors produce it.
Prognosis
 Age: at diagnosis. Cancer relate death more
common if patient is older than 40 years.
 Recurrences common in patients diagnosed
when they were less than 20 years or older
than 60 years.
 Men are twice more likely as women to die.
 Tumors greater than 4 cm have higher
recurrence, death.
Prognosis
 Histology:papillary has 30 year cancer related
death rate of 6%. Follicular has a 30 year cancer
related death rate of 15%.
 Local invasion portends poorer prognosis.
 After surgery, thyroxine is given. Do I scanning
after stopping it for 6 weeks, TSH high now. Do
scan, if some tissue remains on diagnostic dose,
ablate it. Do it again if needed.
 LN metastases not important for prognosis.
 Distant metastases associated with a 68.1-fold
increase in the rate of disease specific death.
Hurthle Cell
 A variant of follicular, also known as oncocytic
carcinoma. 5 year survival 50%.
 More common in women than men, presents in 5th
decade of life.
 Same clinical presentation.
 Cannot diagnose on FNA
 Does not take up iodine, so treat aggressively.
 Thyroid suppression and radioiodine don’t work.
Medullary Carcinoma
 5%, female preponderance
 75% sporadically, 25% familial. Familial
cases are usually all over the gland,
sporadic usually not multifocal.
 MEN 2A, MEN2B and FMTC syndromes.
Men 2a, 2b, FMTC
 MEN 2a is Sipple syndrome,MTC,
pheochromocytoma, hyperparathyroidism.
 MEN 2b is MTC, pheo, ganglionomas, marfan
habitus.
 FMTC is just MTC
 Medullary cancer in these are most aggressive,
younger age, rapid growth and metastases.
 In sporadic you get painless nodule, symptoms of
invasion.
Biochemical Testing
 Stimulating calcitonin release with IV
pentagastrin increases sensitivity of test.
 First measure baseline calcitonin, then give
pentagastrin. Measure calcitonin serially 1.5
and 5 min later.
 Used as tumor marker postop rather than
screening now.
 Use genetic testing for screening.
 Histologically test for calcitonin and CEA.
Treatment
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Total thyroidectomy
Lymph node dissection of level VI.
Parathyroid reimplantation if necessary.
Lymph node mets are very common.
Prophylactic thyroidectomy in children with MEN
2a,b.
 Surveillance with CEA, calcitonin.
 Does not take up iodine, so no radioiodine.
 Prognosis 10 y is 65%.
Anaplastic Thyroid Carcinoma
 Bad.
Indications for Thyroid
Lobectomy
 Suspicion for malignancy
 Compressive symptoms
 Cosmetic issues
 Well-differentiated thyroid carcinoma in
low risk patient (controversial)
Indications for Total
Thyroidectomy
 Well-differentiated thyroid cancer
 Medullary thyroid cancer
 Sarcoma of thyroid
 Lymphoma of thyroid
 Obstructive goiter