Bone Cancer?

Question 1

Name the most common primary form of bone cancer

Answer 1

Osteosarcoma

Question 2

What is another name for osteosarcoma and why is it named that?

Answer 2

Osteogenic sarcoma (bone-forming cancer-> not all primary bone cancers are bone-forming, others are cartilage-forming or fibrous tissue origin)

Question 3

Age of onset for osteosarcoma?

Answer 3

• ~75% before age 20 because of the increased osteoblast activity in people at this age.
• remaining 25% are later in life often accompanied by an underlying bone condition such as Paget’s disease

Question 4

Where on the skeleton does osteosarcoma more commonly occur?

Answer 4

usually in the knee (lower demure or upper tibia/fibula is most commonly affected)

Question 5

What does the soft tissue consist of?

Answer 5

muscles, ligaments, and tendons

Question 6

Osteosarcoma?

Answer 6

• soft tissue are attached to the skeleton and are damaged by neighbouring inflammation
• aggressive cancer (mets to lung and other preferred secondary sites)
• link to RB and TP53

Question 7

RB?

Answer 7

retinoblastoma gene

Question 8

TP53?

Answer 8

Tumor suppressor gene -> tumor suppressor gene

Question 9

Secondary bone cancer?

Answer 9

• ~50% of all cancers will spread to the bone
• > 85% of breast, lung and prostate cancer will spread to the bone
• normal maintenance of bone (bone remodelling) is impacted and surrounding soft tissue is damaged

Question 10

Manifestations?

Answer 10

Swelling and pain

Question 11

Complication?

Answer 11

Fractures

Question 12

Dx?

Answer 12

• xray
• CT
• MRI
• Bone scans
• biopsy

Question 13

Treatment?

Answer 13

• chemo, radiation and surgery
• pain management
• avoid fractures
• bloc excision+bone graft
• amputation

Question 14

Bloc excision?

Answer 14

remove the tumour together with some surrounding tissue and replace with a bone graft