thyroid cancer

Question 1

definition of thyroid cancer

Answer 1

malignancy arising in the thyroid gland,

adenocarcinomas

types include papillary, follicular, medullary and anaplastic

Question 2

aetiology of thyroid cancer

Answer 2

unknown

Question 3

RF for thyroid cancer

Answer 3

childhood exposure to radiation - papillary tumours

medullary thyroid cancers may be familial and are associated with MEN syndrome type 2a or 2b (20% cases)

lymphoma is associated with Hashimoto’s thyroiditis

Question 4

epidemiology of thyroid cancer

Answer 4

incidence 2-4/100000

female more

papillary 20-40yrs

follicular 40-50yrs

anaplastic older

Question 5

symptoms of thyroid cancer

Answer 5

slow growing thyroid neck lump/nodule

pt may complain of discomfort while swallowing and a hoarse voice

Question 6

signs of thyroid cancer

Answer 6

palpable nodules or diffuse enlargement of the thyroid

if cervical nodes are enlarged malignnacy should be suspected

euthyroid

Question 7

pathology of papillary thyroid cancer

Answer 7

70%

multifocal

characteristic orphan Annie pale, empty and grooved nuclei

invade lymphatics with early spread

spread via lungs - jugulodigastric node met is the so-called lateral aberrant thyroid

Question 8

pathology of follicular thyroid cancer

Answer 8

15%

encapsulated

haematogenous spread to the bone and lung

well differentiated

follicular tumours cannot be dx on FNAC as malignancy is based on vascular and/or capsular invasion

Question 9

pathology of medullary thyroid cancer

Answer 9

5-10%

sporadic or part of MEN

well differentiated and derive from parafollicular calcitonin secreting C cells - can be used as tumour marker

Question 10

pathology of anaplastic thyroid cancer

Answer 10

undifferentiated pleomorphic tumopurs

stain for cytokeratins

very aggressive

female more

elderly

Question 11

pathology of lymphomas

Answer 11

rare

2.5% of extra nodal lymphomas

usually diffuse B cells

female more

may have stridor or dysphagia

Assess histology for mucosa-associated lymphoid tissue (MALT) origin (associated with a good prognosis).

Question 12

investigations for thyroid cancer

Answer 12

• bloods
  
  • TFT if hyperthyroid less likely to be malignant
  • bone profile
  • serum thyroglobulin - tumour marker for papillary and follicular tumours
  • calcitonin - tumour marker for medullary
• FNAC or US guided core needle biopsy - allows for histological dx
• excision lymph node biopsy - if enlarged cervical LN
• staging - CT or MRI scan neck, chest, bone scan