Thyroid Cancer

Question 1

presentation

Answer 1

asymptomatic thyroid nodule
lymphadenopathy
hoarseness
dysphagia
thyroid dysfunction is rare
lung, cerebral, hepatic or bone mets

Question 2

risk factors

Answer 2

previous head/neck radiation
previous thyroid disease
FHx

Question 3

papillary carcinoma

Answer 3

70%
40-50yo
RF: previous head/neck radiation
spreads locally and mets to LN
cured by surgical resection
ablative radio-iodine therapy as an adjunct
good prognosis - thyroglobulin as tumour marker

Question 4

follicular carcinoma

Answer 4

20%
mets via bloodstream –> bone
treat same as papillary
two forms:
minimally invasive: well encapsulated, difficult to differentiate from normal thyroid tissue other than by invasion of vasculature
tumour of varying degrees of differentiation: spreads widely and invades venules

Question 5

medullary carcinoma

Answer 5

5%
older adults
can be part of MENIIa/IIb
arise from parafollicular/C cells --> secrete calcitonin
also secrete other hormones - carcinoid or Cushing's
slow growing and indolent
mets to LN
poor prognosis

Question 6

anaplastic carcinoma

Answer 6

less than 5%
elderly
locally aggressive, with rapid and extensive local infiltration
complications: tracheal, SVC obstruction, stridor
total thyroidectomy often not possible - external radiotherapy may give palliation
poor prognosis