The endocrine System - thyroid

Question 1

name the tissue layers of the kneck?

Answer 1

endocrine, respiratory & alimentary layer

Question 2

where does the throid gland sit?

Answer 2

On the surface of the trachea, anterior to neck and inferior to the larynx

Question 3

name the arterial and venous involved in the thyroid?

Answer 3

arterial - sup & inf thyroid artery, venous- thyroid veins, internal jugular vein & brachiocephalic vein.

Question 4

Name the nodes involved in the drainage of the thyroid gland?

Answer 4

upper & lower cervical nodes, pre-tracheal nodes & paratracheal nodes

Question 5

Where do nerves of the thyroid gland devrive from?

Answer 5

cervical sympathetic ganglia

Question 6

what is the thyroids function?

Answer 6

secretes hormone; thyroxine & triiodothyronine & calcitonin (regulates calcium levels

Question 7

what do the thyroid hormones do?

Answer 7

regulate metabolic rate, maintain blood pressure, growth & development

Question 8

name 3 epidemiology and 3 aetiology factors of thyroid cancer?

Answer 8

rare 0.4 of all cancers, UK incidence is 1/100,000, more common in >30
genetic condition, hereditary, radiation induced

Question 9

thyroid cancer presenting signs symptoms?

Answer 9

neck nodules, enlarged nodes, hoarseness, neck pain, pressure symptoms

Question 10

what are thyroid diagnostic investigations?

Answer 10

FMH, examination, ultrasound & fine needle aspiration cytology, RADIOACTIVE IODINE 131 scan, CT & MRI

Question 11

what staging system is used?

Answer 11

TNM: t1, t1a, t1b, t2 - all limited to the thyroid, t3+ advanced disease

Question 12

name thyroid histological types of cancer?

Answer 12

papillary, follicular, medullary, anaplastic, mixed

Question 13

what is the management of each histology type?

Answer 13

papillary & follicular - surgery & post op radioactice ioine 131
medullary - Radical surgery
Anaplastic - Radical surgery & radiotherapy

Question 14

name the types of surgery used

Answer 14

total lobectomy, total thyroidectomy, & central compartment node dissection

Question 15

typical dose & fractionation of thyroid cancer?

Answer 15

60Gy 30# relatively radioresistant - spinal cord shielding after 35gy - 40Gy, palliative 30Gy 10#

Question 16

name some facts about iondine 131 for thyroid treatment?

Answer 16

low iodine diet needed (dont eat; fish & seafood, sweets), 3GBq, used for papillary & follicular cancer, no sex, radioactive

Question 17

what is the patient positioning and techniques used for thyroid cancer?

Answer 17

supine, beam directional shell, chin raised
radical - 3D conformal Rt using ant & post obligue fields, phased, wedges used
palliative - ant & post parallel opposed

Question 18

highlight the palliative & radical fields

Answer 18

dependent on extent of tumour & nodes involved
palliative - sup = mastoid process. inf = carina of trachea, lat = cover clavicular nodes
Radical - sup = hyoid bone, inf= sternal notch, ant = include skin, post = parallel to cord, includes anterior margin of vertebrae

Question 19

name early & late side effects of radiotherapy for thyroid cancer?

Answer 19

laryngitis, oesophagitis, hairloss, weightloss, lymphoedema, dental problems, secondary malignancy