Thyroid cancer

Question 1

How common is thyroid cancer in the UK?

Answer 1

• Fairly rare, about 3500 new cases per year in the UK

Question 2

At what age is thyroid cancer most likely to present in each gender?

Answer 2

• Most commonly between ages 35 and 39 in women and is much more common in women
• much later in males- most commonly 70+

Question 3

What is the survival rate of thyroid cancer?

Answer 3

85% of patients survive their cancer for 10 years or more.
This is much lower though for anaplastic thyroid cancer- only 5% will survive 5 years or more

Question 4

What are the 5 types of thyroid cancer?

Answer 4

• Papillary
• Follicular
• Hurthle cell carcinoma
• Medullary
• Anaplastic

Question 5

What are the characteristics of papillary thyroid cancer?

Answer 5

• The most common with about 90% of thyroid cancers
• more common in women and younger people
• usually slow growing but can spread to lymph nodes

Question 6

What are the characteristics of follicular thyroid cancer?

Answer 6

• often diagnosed in middle age and women
• make up about 4% of thyroid cancers
• sometimes spread to the lungs or bones

Question 7

What are the characteristics of Hurthle cell thyroid cancer?

Answer 7

• Rare type of thyroid cancer- only 2%
• often associated with follicular cancer as it shares similar characteritics

Question 8

What are the characteristics of medullary thyroid cancer?

Answer 8

• rare (2% of thyroid cancers)
• about 25% of medullary cancers are caused by an inherited faulty gene that runs in the family
• can spread to liver and lungs

Question 9

What are the characteristics of anaplastic thyroid cancer?

Answer 9

The least common type of thyoid cancer ( about 1% of cancers) but also the most severe
- usually diagnosed in older people and is more common in women
- the cells dont look like normal throid cells and tend to grow much quicker than other thyroid cancers
- has a very poor prognosis

Question 10

What are some risk factors for thyroid cancer?

Answer 10

• Gender- more common in women (72% of cases are women)
• obesity
• Family history of cancer
• exposure to radiation e.g. chernobyl
• non-cancerous benign diseases of the thyroid e.g. Hashimottos syndrome, goitre
• Gentic factors such as inherited genes- e.g. changes in the Ret gene can cause MEN2A and MEN2B syndromes (Multiple endocrine neoplasia). About 25% of people with medulary thyroid cancer have an inherited faulty gene associated with MEN.

Question 11

What is the link between multiple endocrine neoplasia and thyroid cancer?

Answer 11

Gentic factors such as inherited genes- e.g. changes in the Ret gene can cause MEN2A and MEN2B syndromes (Multiple endocrine neoplasia). About 25% of people with medulary thyroid cancer have an inherited faulty gene associated with MEN.
- most people with MEN syndromes are offered surgery to remove their thyroid

Question 12

What are the symptoms of thyroid cancer?

Answer 12

• Lump in neck
• Enlarged thyroid (goitre)
• Hoarseness of voice
• Sore throat
• Difficulty swallowing

Question 13

What are the treatment options for thyroid cancer?

Answer 13

• Surgery to remove the thyroid gland
• Radiotherapy with radioiodine (I131)
• Chemotherapy- most commonly Doxorubucin or Cisplatin
• If these options are unsuccessful, may use targeted chemotherapy in which they target the vascular endothelial growth factor receptor pathways as the thyroid is vascular-rich
  e.g. Vandetanib (Medullary)- targets the VEGFR2 and EGFR
  Cabozantinib (medullary)- inhibits c-MET and VEGFR2
  Lenvatininb (follicular & papillary)- inhibits VEGFR and FGFR

Question 14

What is VEGFR2?

Answer 14

Vascular endothelial growth factor receptor

Question 15

What is EGFR?

Answer 15

Epidermal growth factor receptor

Question 16

What is c-MET?

Answer 16

Mesenchymal epithelial transition factor

Question 17

What is FGFR?

Answer 17

Fibroblast growth factor receptors