Thyroid cancer

Question 1

What are the types of thyroid cancers?

Answer 1

(well-differentiated thyroid carcinomas) papillary, follicular carcinoma
(poorly differentiated carcinomas) medullary (parafollicular C cell), anaplastic carcinoma

Question 2

What are the genes associated with medullary carcinomas?

Answer 2

MEN2 (RET gene mutations) or familial medullary carcinoma.

Question 3

What are the clinical features of thyroid cancer?

Answer 3

(Early) Often asymptomatic
Firm, painless thyroid nodules
(Late) Dyspnea
Dysphagia
Hoarseness (vocal cord paresis)
Horner syndrome

Question 4

How are thyroid cancers diagnosed?

Answer 4

(Thyroid function tests) Basal TSH
fT3 and fT4
(Tumour markers) Thyroglobulin (Tg) = should be measured as a follow‑up to thyroidectomy in follicular or papillary thyroid carcinoma
Calcitonin = For supporting diagnosis of medullary thyroid carcinoma and follow‑up
(Ultrasound) irregular margins > 1 cm + calcifications = suspect cancer
(Thyroid scintigraphy) decreased tracer uptake suggests a malignant non-functioning (cold) nodule
(Fine needle aspiration)

Question 5

What is the treatment for thyroid cancer?

Answer 5

(Well-differentiated) (Surgical management) Tumor < 1 cm = hemithyroidectomy
Tumor 1–4 cm = hemithyroidectomy or total thyroidectomy
Tumor >( 4 cm, extrathyroidal spread, or metastasis = total thyroidectomy with neck dissection
(Radio-iodine therapy + TSH suppression follow-up)

(Poorly-differentiated) Total thyroidectomy with adjuvant radiochemotherapy if operable
Radiochemotherapy if locally advanced, inoperable