Thyroid Cancer

Would would you give Levothyroxine to Suppress TSH concentrations when treating differentiated thyroid carcinoma?

1. Avoid hypothyroidism- after surgery or radioactive iodine. 2. to Decrease the risk of recurrence of cancer.

What risk factors increase ones chance for Thyroid Cancer?

1. Exposure to radiation. 2. Familial Thyroid Carcinoma or Thyroid Cancer Sydrome (*MEN 2*). 3. Hoarseness. 4. Fixation of Nodule. 5. Ass'n cervical lymphadenopathy.

On imaging, what characteristics denote the thyroid nodule as "suspicious" for cancer?

1. Microcalcifications. 2. Nodule *Hypoechogenicity* (dark in color on ultrasound). 3. Irregular margins. 4. Taller than wider on Transverse view. 5. Intranodular vascularity.

What thyroid cancers are included in Differentiated Thyroid Carcinoma?

1. Papillary Thyroid Carcinoma. 2. Follicular Carcinoma.

How do you treat Anaplastic Thyroid Carcinoma?

1. Surgery, radiation, &/or Chemotherapy. 2. End of life comfort/care options- b/c this type of cancer is *extremely aggressive* and pts only have a median survival of *5 months*.

What are the treatment options for Differentiated Thyroid Carcinoma?

1. Thyroidectomy. 2. Radioactive Iodine Treatment. 3. TSH suppression. 4. External beam irradiation. 5. Chemotherapy.

What is the clinical presentation of Anaplastic Thyroid carcinoma?

1. expanding thyroid mass. 2. s/s of pain, dysphonia, dyspnea, dysphagia. 3. jugular lymph node involvement. 4. systemic metastases.

In what population is Thyroid Cancer typically seen in?

People Younger than 55

Parafollicular Cells (C Cells) secrete what hormone that may be measured when analyzing for Medullary Thyroid Carcinoma?

Calcitonin

How do you diagnosis Anaplastic Thyroid Carcinoma?

FNA biopsy. Note: may have to do surgical biopsy for confirmation.

How is Medullary Thyroid Carcinoma diagnosed?

Fine Needle Aspiration Biopsy.

What is the most accurate and cost effective method for evaluating thyroid nodules?

Fine Needle Aspiration Biopsy.

When should you order a Fine Needle Aspiration Biopsy?

If Hypoechoic component on imaging with *ONE* additional suspicious finding on Imaging. Note: especially concerned if TSH values are euthyroid.

When would you order a Radionuclide Thyroid Scan for assessing thyroid cancer? Why?

If TSH is *Low.* You want to determine if the Nodule is a "Hot" vs. "Cold" nodule. Note: *Hot Nodules*: have high uptake of iodine and are USUALLY *benign.* (hyperthyroidism) *Cold Nodules:* have low uptake of iodine and may be *malignant.*

When would you order a thyroid ultrasound?

If the patient has a known or *suspected* thyroid nodule. Note: ultrasound exam should include the neck for any suspicious cervical lymph nodes.

When would you order a CT or MRI if you suspect thyroid cancer?

If you believe that there is other lymphadenopathy that is too deep to be detected by ultrasound. Specifically helpful in assessing *substernal region*.

When would you use Radioiodine therapy for differentiated thyroid carcinoma?

Known *Residual* (post surgical remnant tissue) or *Metastatic* (spread to different tissues) thyroid Carcinoma.

Differentiate between MEN IIa & MEN IIb.

MEN IIa: 1. Medullary thyroid carcinoma. 2. Pheochromocytoma. 3. Primary hyperparathyroidism. MEN IIb: 1. Medullary Thyroid Carcinoma. 2. Pheochromocytoma. 3. Marfanoid Habitus. 4. Muscosal Neuromas. 5. Ganglioneuromatosis

What is the most common thyroid Cancer?

Papillary Thyroid Carcinoma.

Because you *cannot* determine a benign vs. malignant *Follicular Nodule,* what do you do?

Pts with Follicular Nodules need to be take to Surgery to determine if it is a *Follicular Adenoma* vs. a *Follicular Carcinoma.*

In what population do you typically see Medullary Thyroid Carcinoma in?

This type of cancer is Rare and usually *Sporadic*, but may be a part of *MEN 2 Syndrome*

What is the most important treatment for the best prognosis for differentiated thyroid carcinoma?

Thyroidectomy.

When is external beam irradiation used in the treatment of differentiated thyroid carcinoma?

Used infrequently EXCEPT as a palliative treatment for a locally advanced, unresectable disease.

What is the treatment of choice for Medullary thyroid Carcinoma?

Total thyroidectomy.

What is Medullary thyroid Carcinoma?

Unlike papillary thyroid cancer and follicular thyroid cancer that arise from thyroid hormone producing cells, medullary thyroid cancer is a tumor that originates from the parafollicular cells (also called C cells) of the thyroid.

When is Chemotherapy used to treat differentiated thyroid carcinoma?

When all surgical and radiation therapy options have been tried.

In what population do you typically see Anaplastic Thyroid Carcinoma?

Women ages 60-70