Thyroid cancer Flashcards
When do otolaryngologists recommend and perform removal of thyroid nodules?
reasonable risk of being cancerous
- man (nodules more common in F but more likely to be benign)
- Young
- Large
The standard accepted and effective method for determination of the contents of a thyroid mass or nodules is ___?
Fine needle aspiration biopsy with or without US guidance.
FNAB diagnosis of malignant cells,is an obvious indication for surgery, either a total thyroid lobectomy or a total thyroidectomy
What do you do if the FNAB is indeterminant>
a repeat FNAB with the aid of an ultrasound is necessary to ensure sampling efficiency of the tissue
T/F If a patient doesnt have any RF, there is a high degree of probability that the nodule is benign and doesnt need to be followed-up
F - Observation
When multiple nodules are found, the thyroid is classified as a what? Which nodule do you biopsy on FNAB?
multinodular thyroid or goiter
the dominant or largest nodules are biopsied.
T/F • Radionuclide thyroid scans have become less essential to the diagnostic workup of nodules with the development and refinement of ultrasound and fine-needle aspiration techniques.
True
What are the 2 essential classifications of thyroid cancer?
- Well differentiated (papillary and follicular)
2. Other ( includes less well-differentiated forms of thyroid cancer, including medullary, and anaplastic. Lymphoma)
Make up ~80% of thyroid cancers histologically (Orphan annie cells and psammoma bodies) and often mets to neck LN
What kind of carcinoma is this?
Papillary carcinoma
Factors predictive of a better prognosis for papillary carcinoma?
small size (less than 1.5 centimeters (cm)) and absence of thyroid gland capsule involvement.
T/F Papillary carcinoma follows a much more indolent course when discovered in people under age 40 but these pts also have high rate of recurrence
T
T/F When treating papillary carcinoma total thyroidectomy may significantly decrease the local recurrence rate and mortality vs subtotal
T
When treating papillary and follicular carcinoma radioactive iodine and thyroid hormone suppression have a increased incidence of recurrence
False - decreased compared to total alone
What are the greatest risks of thyroid surgery?
- hypoparathyroidism secondary to injury or removal of the parathyroid glands
- Recurrent laryngeal nerve injury, which may result in hoarseness, shortness of breath, and reduced exercise tolerance
What carcinoma makes up ~ 15% of thyroid cancers?histologically
Follicular carcinoma
What findings in follicular carcinoma are essential for diagnosis and cannot be determined by a FNA? Why cant you use FNA?
- Capsular and/or lymphovascular invasion
2. Cytopathologically, the cells may also look fairly benign on FNA
Which type of carcinoma metastasizes hematogenously?
Follicular carcinoma
What are the 3 types of follicular cell carcinoma and which is most aggressive?
- microinvasive
- macroinvasive
- Hurthle cell carcinoma (most aggressive)
Why is total thyroidectomy plus radioactive iodine the treatment of choice for follicular thyroid cancer?
Iodine is concentrated in normal thyroid tissue. If all thyroid tissue is removed this allows a higher dose to be delivered to the remaining tissue while using lower amts.
What carcinoma makes up ~ 6-10% of thyroid cancers?
Medullary carcinoma
What cells are the origin for medullary carcinoma?
Parafollicular or C-cells
What are 2 forms of medullary carcinoma and are tumors typically unilateral or bilateral?
- Familial (10-20%) and sporadic)
2. Bilateral
Involves parathyroid adenoma, medullary carcinoma, and pheochromocytoma. RET proto-oncogene is positive in most pts with this. Is this MEN IIA medullary carcinoma or MEN IIb?
MENIIa
What kind of screen should all patients with medullary carcinoma get to determine increase in circulating CATACHOLAMINES?
What happens if this is positive?
Urinary metanephrine screen
pheochromocytoma should be located and excised first
All first-degree relatives of patients with medullary carcinoma should be tested for ___ levels?
Calcitonin
does not have a parathyroid component, but includes a Marfanoid habitus and mucosal neuromas. Is this MEN IIA medullary carcinoma or MEN IIb?
MEN IIb
How can you treat medullary carcinoma?
Total thyroidectomy with paratrachceal, central compartment neck dissections
T/F Thyroid C-cells do not absorb radioactive iodine?
T - So RAI is seldom effective as adjuvant tx
What kind of carcinoma is a rare, aggressive cancer with a very poor prognosis?
Anaplastic carcinoma
What can a surgeon do for anaplastic carcinoma? What other tx are there?
Rarely resectable so role of the surgeon is often limited to establishing diagnosis through open biopsy and securing the airway, which usually involves a tracheotomy.
often treated with external beam radiation and systemic chemotherapy, since 50% of patients will have pulmonary metastases at the time of diagnosis.
What kind of cancer is a rapidly growing tumor, which frequently compromises the airway and clinically resembles anaplastic carcinoma?
Thyroid lymphoma
Patients with thyroid lymphoma may have a background of what condition?
Hashimoto’s thyroiditis, an autoimmune condition characterized by lymphocytic infiltration
What type of lymphocytes are the origin of thyroid lymphomas?
Most commonly B-cell
How can you tx and cure thyroid lymphomas?
usually achieved by using a combination of chemotherapy and radiation
