Thyroid Cancer

Question 1

Risk factors

Answer 1

• ionising radiation
• MEN Syndrome (for MTC)

Question 2

Clinical features of Thyroid Cancer

Answer 2

• usually asymptomatic

Compressive effects:
- hoarseness
- dyspnea
- dysphagia

• lymphadenopathy may be present

Question 3

Diagnosis of Thyroid Cancer

Answer 3

• Palpation
• Thyroid function test
• Echo: hypoechogeneus node,
  microcalcifications, peripheral halo
  absence, irregular borders, intranodular
  vascularisation
  
  • > 1cm node on US
• FNAB
• Scintigraphy (99mTc-pertehnetat+MIBI
  scan)
• Tg+antiTgAB for DTC
• Calcitonin and CEA for MTC

Question 4

Types of Thyroid Cancer

Answer 4

Differentiated:
- Papillary
- Follicular

Undifferentiated:
- medullary
- anaplastic

Question 5

Basic Treatment of Differentiated Thyroid Cancer? (papillary and follicular)

Answer 5

• Total or hemi thyroidectomy
• Possible need for Radioablative treatment
• Assess levels of serum thyroglobulin and thyroglobulin antibody during post-op

Question 6

Basic Treatment of Undifferentiated Thyroid Cancer?

Answer 6

• Total thyroidectomy
• LN dissection only in pre-op finding
• Serum calcitonin and CEA levels

Question 7

Tumour staging of Thyroid Cancer

Answer 7

T1: less than 2cm (limited to thyroid)
T2: more than 2cm (limited to thyroid)
T3: tumour > 4cm (extends beyond)
T4: tumour invades nearby organs

Question 8

Nodal Staging of Thyroid Cancer

Answer 8

N0- no regional metastasis
N1a - metastasis at level VI
N1b - cervical or mediastinal involvement

Question 9

Metastasis Staging of Thyroid Cancer

Answer 9

M0- no metastasis present
M1- distant metastasis present

Question 10

When is radioablative therapy indicated?

Answer 10

RAI is indicated only in high-risk and intermediate-risk TC following total thyreoidectomy

Question 11

What is the method of choice for radioablative therapy for DTC?

Answer 11

Administration of 131I

Question 12

Drug choice for RAI refractory, advanced symptomatic DTC?

Answer 12

Single Lesion - local regional therapy

Multiple lesions - local regional therapy plus lentinivib/sorafenib

Question 13

What is the Bethesda System? What are the indicated treatment?

Answer 13

6 categories

1) Unsatisfactory (repeat US every 3 months)

2) Benign (clinic and US follow up)

3) Atypia of un-determined significance (repeat US)

4) Follicular nodule/suspicious FN (molecular testing/lobectomy)

5) Suspicion of malignancy (surgical lobectomy/ total thyroidectomy)

6) Malignant (total thyroidectomy)

Question 14

What is the treatment for non-resectable anaplastic TC?

Answer 14

BRAF
mutated:
- Dabrafenib + trametinib

wild type:
- supportive care
- palliative external beam radiotherapy

Question 15

What is the treatment for resectable anaplastic TC?

Answer 15

• total thyroidectomy +/- neck dissection
• consider post-op radiotherapy

Question 16

What is the post-operative FU approach?

Answer 16

• assess serum levels of calcitonin or TSH levels (depends if MTC or DTC)
• US of neck
• Scintigraphy to assess for any metastases