Thyroid Cancer Flashcards
What is the cause of a thyroglossal duct cyst?
Ectopic thyroid tissue and/or cysts present along the course of the thyroglossal duct
What is the difference between a thyroglossal duct cyst, and a cervical cyst?
Thyroglossal is midline
Cervical is lateral to the SCM
What muscle lie in front of the thyroid? (4)
Strap muscles:
- Thyrohyoid
- Sternothyroid
- Sternohyoid
- Omohyoid
What is the blood supply to the thyroid? (2)
Superior thyroid –external carotid artery
Inferior thyroid artery – thyrocervical trunk
What is the thyroid IMA, and when is it important?
Artery from the thyrocervical trunk that runs anteriorly along the trachea to the thyroid.
Need to know if tracheostomy
What is the blood supply to the superior pole of the thyroid? What is this a branch of?
Superior thyroid artery
External carotid artery
What is the middle thyroid artery a branch of?
There is no middle thyroid artery
What are the veins that drain the thyroid?
Superior thyroid vein
Middle thyroid vein
Inferior thyroid vein
What is the nerve that runs alongside the thyroid within the carotid sheath?
CN X
The inferior thyroid vein drains where?
Into the brachiocephalic cein
The superior thyroid vein drains what part of the thyroid? Where does it drain to?
Drains the superior pole
Drains into the IJV
What middle thyroid vein drains what part of the thyroid? Where does it drain to?
Drains the lateral aspect of the gland
Drains into the IJV
Where does the recurrent laryngeal nerve lie in relation to the thyroid?
Deep to it– in the tracheoesophageal groove
What is the course of the vagus nerve on the right side? Left side?
Right = wraps around the thyrocervical trunk
Left = wraps around the arch of the aorta
What does the recurrent laryngeal nerve innervate?
All intrinsic muscles to the larynx except the cricothyroid muscle
What is the groove that the recurrent laryngeal nerves runs in?
Tracheoesophageal groove
What artery does the recurrent laryngeal nerve run near?
Inferior thyroid artery
True or false: there is a high incidence of asymptomatic thyroid nodules
True
What are the two major types of thyroid nodules?
Solitary nodules
Multinodular goiter
What is the risk of malignancy for solitary thyroid nodules?
5%
What is the risk of malignancy for a multinodular goiter?
1%
What are the characteristics of multinodular goiters (all similar, or all different)?
Multiple palpable nodules of similar size and consistency
What should always be asked about in the history when evaluating a thyroid nodule?
h/o radiation to the head/neck
What percent of thyroid nodules are malignant?
10%
What is the most effective method of diagnosing thyroid nodules? What is the false negative rate of this?
FNAB
False negative = 1% ish
What is most suspicious for malignancy: a homogenous or a heterogeneous thyroid nodule
Heterogeneous
True or false: a FNA can be done in the office setting or with radiology
True
Which is more likely malignant: hot or cold nodules?
Cold
What percent of all cancers in the US are thyroid cancers? What percent of all endocrine cancers are thyroid cancers?
1.5% of all CAs
95 of endocrine CAs
What are the four types of thyroid cancers in descending order of incidence/badness?
Papillary
Follicular
Medullary
Anaplastic
What are the three differentiated types of thyroid cancer?
- Papillary
- Follicular
- Hurthle cell
Which thyroid cancer is made up of undifferentiated cells?
Anaplastic