BONE METASTASIS

Question 1

What is this lesion? What’s condition is it classically seen in?

Answer 1

Osteosclerotic (osteoblastic) lesion

Prostate cancer

Question 2

What is this lesion? What condition is it commonly seen in?

Answer 2

Osteolytic lesion

Multiple myeloma

Question 3

Primary bone tumours are more likely in which demographic? Explain why

Answer 3

Children and young adults (esp male)

Growth plates have dividing cells, boys are taller

Question 4

What are the three main ways in which primary bone tumours present?

Answer 4

• Incidental finding
• Bone pain
• Pathological fracture

Question 5

What is shown in the x-ray?

Answer 5

Osteoid osteoma

benign bone tumour with central osteoid core (radiolucent: clear), surrounded by reactive bone

found at surface of cortex/diaphysis

Question 6

Which gene mutation is associated with the development of osteomas? An osteoma in these patients may proceed the development of which symptoms?

Answer 6

ACP gene mutation: Gardener’s syndrome, variant of familial adenomatous polyposis (FAP)

May preceed development of colon symptoms

Question 7

What is the most common primary bone tumour? Which cells are affected?

Answer 7

Osteosarcoma

Malignant bone tumour of osteoblasts

Question 8

In treating osteosarcoma, what should you presume about all patients? How does this influence treatment?

Answer 8

Presumed all patients have metastasis, treatment with surgery alone (amputation or resection) leads to poor survival rates

Chemotherapy may be given before surgery to shrink tumour and is always given as part of treatment

Question 9

Which primary bone tumour has the youngest age of presentation of all bone tumours?

Answer 9

Ewing sarcoma

→ mainly affects children (80% of cases <20)

Question 10

What is the most likely diagnosis of this patient? What is the treatment? What is the overall survival?

Answer 10

Ewings sarcoma

• Treat with surgery, chemotherapy, radiation
• 5 year survival: 70% in localised disease; 33% if metastasis at diagnosis
• Ewings sarcoma is aggressive with early metastasis

Question 11

The presentation of a Ewings sarcoma can mimic the presentation of which other bone condition? How do you differentiate?

Answer 11

Osteomyelitis: both present with painful mass over bone, which is warm and swollen and patient may have fever and leucocytosis

Bone cultures and tumour aspiration will be sterile

Question 12

85% of cases of Ewing sarcoma are associated with which genetic mutation?

Answer 12

Genetic translocation between chromosomes 11 and 22

Question 13

Which bone tumour is benign but locally aggressive? Explain why and describe where this tumour normally occurs in a bone

Answer 13

Giant cell tumour (osteoclastoma)

Multinucleated giant osteoclasts cause lots of local bone resorption

Occurs in epiphyses: most important tumour that occurs in this region

Question 14

A tumour arising laterally from a growth plate at the metaphysis is what type of tumour?

Answer 14

Osteochondroma

​benign: can rarely undergo malignant conversion to chondrosarcoma

Question 15

Tumour is this most likely to be?

Answer 15

Chondroma: benign tumour of cartilage

Occurs in small bones

Question 16

What should you check first in someone that presents with bone pain/fractures? How does this help you reach a differential diagnosis?

Answer 16

Calcium + parathyroid hormone levels

• Normal calcium + PTH: primary bone condition e.g. osteoporosis, tumours
• Low calcium + high PTH: most likely vitamin D deficiency
• High calcium + high PTH: hyperparathyroidism

Question 17

Review causes of long bone tumours according to location

Answer 17

Question 18

Prior radiation increases risk of which type of bone cancer?

Answer 18

Osteosarcoma