Thyroid cancer

Question 1

What is the effect of thyroid adenomas?

Answer 1

usually non functional

can secrete T3/T4 (leads to thyrotoxicosis)

Question 2

What is the macroscopic appearance of a thyroid adenoma?

Answer 2

discreet solitary mass
encapsulated by collagen cuff
neoplastic thyroid follicles (follicular adenoma)

Question 3

What is the mutation causing follicular adenomas?

Answer 3

Mutation in TSHR signalling pathway

Question 4

What can follicular adenoma be mistaken for?

Answer 4

follicular carcinoma

Question 5

What is the most common differentiated thyroid cancer?

Answer 5

papillary carcinoma

Question 6

How do papillary carcinomas present?

Answer 6

Solitary nodule
maybe multifocal
usually cystic
may often be calcified

Question 7

What mutation causes papillary carcinoma?

Answer 7

MAP kinase pathway activation

Question 8

What is the prognosis with papillary carcinoma?

Answer 8

95% 10 year survival

good because it’s differentiated

Question 9

What conditions are associated with papillary carcinoma?

Answer 9

Hashimoto’s thyroiditis

Question 10

What is the mode of metasteses in papillary carcinoma

Answer 10

lymphatic

haematogenous

Question 11

Where does papillary carcinoma metastasise to?

Answer 11

bones, lungs, liver, brain

Question 12

What is the second most common differentiated thyroid cancer?

Answer 12

follicular carcinoma

Question 13

What is the presentation of a follicular carcinoma?

Answer 13

single nodule
painless
slow growing
non functional

Question 14

What is the mode of mets in follicular carcinoma?

Answer 14

Haematogenous

need vascular or capsular invasion

Question 15

Where does follicular carcinoma metasts to?

Answer 15

bone, liver, lungs

nb, blood brain barrier?

Question 16

What is the prognosis for follicular carcinoma?

Answer 16

depends on level of invasion

minimal invasion the 90% survival at 10 years

Question 17

What is the etiology in Medullary thyroid carcinoma?

Answer 17

sporadic (40s+50s)
multiple endocrine neoplasia (MEN) (young)
Familial (40s+50s)

Question 18

What is the mutation in MTC?

Answer 18

c cell mutation

secretes calcitionin

Question 19

What is the presentation of MTC?

Answer 19

sporadic: solitary nodule
familial: bilateral/multicentric (c cells)

Question 20

What is the histolgical appearance of MTC?

Answer 20

spindle cell
nest arrangement
trabeculae/follicles

Question 21

What are the local symptoms of MTC?

Answer 21

dysphagia
hoarseness
airway obstruction

Question 22

What are the paraneoplastic signs of MTC?

Answer 22

diarrhoea

Cushings signs

Question 23

What is MTC associated with?

Answer 23

amyloid deposition

Question 24

How common are MTCs? What grade are they?

Answer 24

Rare

High grade

Question 25

What is the etiology of anaplastic tumours?

Answer 25

older patients | PMHx differentiated tumour

Question 26

Why are anaplastic tumours aggressive?

Answer 26

undifferetiated

Question 27

Why is survival poor with anaplastic tumours?

Answer 27

Rapid growth | Invades neck structures

Question 28

What factors increase the likelihood of a thyroid tumour being malignant?

Answer 28

``` Male New nodule 50 years Vocal cord palsy Nodule increasing in size lesion >4cm Hx neck radiation ```

Question 29

What investigations do you do in a suspected thyroid tumour?

Answer 29

US guided FNA laryngoscopy if vocal nerve palsy excision and biopsy lymph node

Question 30

What test(s) is NOT done in suspected thyroid tumour?

Answer 30

NO isotope scan | NO CT/MRI?

Question 31

How do you assess cytology and what sample is needed?

Answer 31

Thy1-Thy5 | FNA

Question 32

What is the grading of Thy1-Thy5?

Answer 32

``` Thy1-insufficient sample Thy2-benign Thy3-atypical, suspected benign Thy4-atyplical, suspected malignancy Thy5-malignant ```

Question 33

What grade are follicular lesions and why?

Answer 33

All Thy3 difficult to assess no capsule

Question 34

What are the surgical options for thyroid cancer?

Answer 34

lobectomy and isthmusectomy subtotal thyroidectomy total thyroidectomy

Question 35

When is lobectomy and isthmusectomy appropriate?

Answer 35

papillary microcarcinoma <1cm minimally invasive follicular carcinoma low risk AMES

Question 36

When is (sub)total thyroidectomy appropriate?

Answer 36

``` DTC and nodes DTC and distant mets Bilateral/multifocal DTC DTC with extrathyroidal spread High risk AMES ```

Question 37

When should lymph nodes be removed?

Answer 37

Showing signs of macroscopic disease | use judgement