Thyroid cancer

Question 1

Thyroid cancers

Answer 1

Papillary 80% 
Follicular 10% 
Medullary 5%
Anaplastic
Lymphoma

Question 2

Papillary thyroid cancer

Answer 2

Associated with irradiation
Aged 20-40

Cell origin: Follicular cells - Thyroglobulin tumour marker

Spread: Lymph nodes + lung + lateral thyroid

Tx:
Total thyroidectomy
± node excision
± radioiodine
T4 to suppress TSH

Question 3

Follicular Ca

Answer 3

F>M = 3:1
40-60

Cell origin: Follicular cells- thyroglobulin tumour marker

Spread: Blood → bone
and lungs

Tx:
Total thyroidectomy +
T4 suppression +
Radioiodine

> 95% 10ys

Question 4

Medullary Ca

Answer 4

30% are familial - e.g. MEN2
Men: young
Sporadic: 40-50

Cell origin: Parafollicular C-cells

Markers: CEA and calcitonin
markers

Tx:

Do phaeo screen pre-op
Thyroidectomy +
Node clearance
Consider radiotherapy

Question 5

Anaplastic (rare)

Answer 5

F>M = 3:1
>60 yo

Cell origin: Undifferentiated
follicular cells

Spread: Rapid growth
Aggressive: local,
LN and blood.

Tx:
Usually palliative
May try thyroidectomy +
radiotherapy
<1% 10ys

Question 6

Lymphoma

Answer 6

Cell origin: lymphocytes
Associated with hashimoto’s disease

Tx Chemo-radiotherapy

Question 7

Presentation

Answer 7

Painless neck mass
Cervical mets
Compression symptoms:
- oesophagus- dysphagia
- trachea - Stridor
- SVC obstruction

Solitary, solid lesion

Question 8

Risk factors

Answer 8

Young, male

Radiation exposure

Question 9

Indications for thyroid Surgery

Answer 9

Pressure symptoms
Relapse hyperthyroidism (>1 failed drug Rx)
Cosmesis
Carcinoma

Question 10

Surgery practicalities

Answer 10

Euthyroid pre-op with antithyroid drugs

• Stop 10 days prior to surgery
• Alternatively give propronalol
• Check for phaeo pre-op in medullary carcinoma
• Laryngoscopy: check vocal cords pre- and post-op

Question 11

Complications of surgery

Answer 11

Early:
• haemorrhage → haematoma - can cause airway obstruction - remove wound clips

• Laryngeal oedema
- airway obstruction

• Recurrent laryngeal nerve palsy

• Right RLN more common
• Damage to one - hoarse voice
• Damage to both → obstruction needing trachyostomy

• Hypoparathyroidism
- ↓ Ca2+

• Thyroid storm

Late:
Hypothyroidism
Recurrent hyperthyroidism
Keloid scar

Question 12

Investigations

Answer 12

Thyroid examination
Basic obs
Bloods - FBC, U+Es, LFTs, TFTs, tumour markers
USS - first line