Thyroid Cancer Flashcards
How Do Aggressive Thyroid Cancers Present?
1) Most present as a rapidly enlarging neck mass.
2) This is often associated with
- Hoarseness
- Pain or discomfort
- Erythema of the overlying skin
Airway Management in patient’s with aggressive thyroid cancer.
While patients may have a large neck mass causing tracheal deviation and compression of other critical structures of the neck:
1) Most patients will not require emergent tracheotomy to maintain the airway
2) ATA guidelines do not recommend routine tracheotomy in these patients - only in response to an imminent threat
- Tracheotomy should only be performed in response to critical airway compromise, and should not be undertaken electively. Tracheotomy should not be performed in a patient with a stable airway.
- Tracheotomy should be performed in those patients with unresectable tumors in whom imminent suffocation is likely and whose dyspnea does not respond to high dose steroids
- Extended length tracheostomy tubes are frequently needed.
- A tracheal stent can be used to stabilize the airway
Pretreatment imaging for aggressive thyroid cancer.
1) Neck CT with IV contrast
2) FDG-PET CT
3) Thyroid U/S alone is of limited value
4) There is no role for radioactive iodine in the treatment of anaplastic thyroid carcinoma except in cases with a dominant DTC tumor component requiring therapy itself with radioactive iodine.
5) The brain should be imaged
Speed of workup for anaplastic thyroid carcinoma.
The evaluation of anaplastic thyroid carcinoma should be completed within a few days:
1) If ATC is suspected, a core needle biopsy should be performed; an FNA biopsy can also be helpful.
2) CT scan of the Neck, Chest, Abdomen, and Pelvis
3) Tracheotomy if indicated
The differential diagnosis of a rapidly enlarging thyroid area mass
1) Anaplastic thyroid carcinoma
2) Primary thyroid lymphoma
3) Medullary thyroid cancer
4) Primary thyroid squamous cell carcinoma
5) Metastatic adenopathy from upper aerodigestive tract malignancies
6) Sarcoma
Imaging in Anaplastic Thyroid Cancer
1) Neck CT with IV contrast
2) FDG-PET scan
3) No role for the following:
- U/S alone
- No role for radioactive iodine except in cases to treat a dominant DTC tumor
4) Imaging of the brain to r/o intracranial masses
Note: the above evaluation should be completed within a few days. Any unnecessary delay in assessment may permit ATC to progress from potentially resectable to unresectable and imminently life threatening.
Pathologic Evaluation of a Rapidly Growing Neck Mass
1) FNA biopsy can be helpful in establishing diagnosis
2) Core needle biopsy is preferred over FNA biopsy
Prevalence and Mortality of Anaplastic Thyroid Carcinoma
1) Anaplastic Thyroid Carcinoma comprises 1-2% of all thyroid cancers
2) Anaplastic Thyroid Carcinoma accounts for 20-50% of all thyroid cancer deaths
What is the relationship between Anaplastic Thyroid Carcinoma and Differentiated Thyroid Cancer?
1) They often coexist in the same patient.
2) About half of patient’s with anaplastic thyroid carcinoma have a coexistent DTC - anaplastic thyroid carcinoma may originate from a preexisting papillary thyroid carcinoma
What are the Survival Rates in Anaplastic Thyroid Carcinoma?
1) Mean survival rate = 7 months
2) One year survival = 11%
3) Younger patients have better survival rates
Prognostic Factors in Anaplastic Thyroid Carcinoma.
Better Survival in:
1) Patients with younger age
2) Limited Stage disease (AJCC Stages IVA and IVB)
3) Patients treated with multimodality therapy have better prognosis
4) Surgical resection is a strong predictor of overall survival in ATC
- Surgical resection attempted in about half of patients
- Extent of involvement of the visceral compartment of the neck is dominant determinant of morbidity associated with and feasibility of surgical resection of ATC: evaluate tracheal, laryngeal, and esophageal involvement with radiographic studies and endoscopy
