MSK malignancies

Question 1

Red flags for bone pain

Answer 1

• pain when rest
• night pain
• lumps present (tender, enlarging, deep to fascia, above 5cm in diameter)
• loss of function of joint
• neurological symptoms
• unwell or weight loss

Question 2

What are the 3 things we should do when assessing someone with bone pain?

Answer 2

Look at the bone
Feel the bone - assess any masses present, note the size, shape, pain, tethered to skin or deep tissues etc.
Move the bone - range of movement and neurovascular status

Question 3

What are urine Bence Jones protein and what are they diagnostic of?

Answer 3

immunoglobulin light chains found in the urine and are diagnostic of multiple myeloma

Question 4

What is a zone of transition? What does it help us differentiate?

Answer 4

Most reliable indicator in determining whether an osteolytic lesion is benign or malignant
Narrow zone of transition: sharp, well defined border and is a sign of slow growth
Wide zone of transition: ill-defined border and is a sign of aggressive growth

Question 5

When would you expect to see an ‘onion skin appearance’ in a bone?

Answer 5

In a fast growing process, the periosteum does not have time to respond and cannot form new bone as fast. This leads to an ‘onion skin’ appearance as the process of forming new bone is constantly interrupted.
Can see in Ewings, osteosarcoma and osteomyelitis

Question 6

When would you expect to see a ‘sunburst’ appearance in bone?

Answer 6

The sunburst appearance occurs when there is a rapid and steady process which does not allow the periosteum to lay down a shell of bone. Tiny fibres connecting the periosteum to the bone (sharpey’s fibres) ossify and leads to a sunburst or hair on end appearance.
Can see in osteosarcoma and Ewing’s

Question 7

When would you expect to see ‘codemans triangle’ on bone x ray?

Answer 7

The codemans triangle occurs when there is a rapid and steady process and there is no time for the sharpey fibres to ossify. Instead, only the edges of the raised periosteum will ossify.
Can see in osteosarcoma, ewing’s, Germ Cell Tumour, osteomyelitis and metastases

Question 8

What information can CT scan give us regarding bones?

Answer 8

Info on whether the lesion is intra or extra medullary
Determine whether it is solid or cystic
Neoplastic or inflammatory
Look for cortex involvement

Question 9

What information can MRI scan give us regarding bones?

Answer 9

Visualise the bone marrow contents and differentiate between malignant and benign tumours

Question 10

What information can a bone scan give us? Can it differentiate between malignant and benign?

Answer 10

Can show us ‘hot spots’ where there are high levels of bone turnover and can visualise multiple lesions or metastases from different areas in the body.
It cannot differentiate between malignant and benign tumours.

Question 11

What information can a PET scan give us, how does it work?

Answer 11

PET scan detects changes in tissues that use glucose as their energy source
Cancers use a lot of glucose so they get picked up in the scan
Involves injecting a small amount of radioactive substance which travels to the place where the glucose if being used up and shows up on the scans.

Question 12

Why do we perform a biopsy of the bone? What are some ways we can biopsy?

Answer 12

To confirm a suspected diagnosis using fine needle aspiration, tru-cut biopsy, incision or excision biopsies.

Question 13

Describe the Enneking classification of tumour grading (1,2,3)

Answer 13

Grade 1 - latent

• Well defined margin, grows slowly then stops
• May heal spontaneously and very low risk of recurrence

Grade 2 - active

• Progressive growth limited by natural barriers
• Well defined margin but may expand and thin cortical bone
• Negligible recurrence after marginal excision

Grade 3 - aggressive

• Growth not limited by natural barriers
• Metastasis present in 5% of patients
• High recurrence following marginal resection (extended resections needed)

Question 14

How do we manage suspected bone sarcoma?

Answer 14

referred for plain x-ray via 2 week wait (adults) and 48h wait (children)
If x ray is suspicious = refer to specialist bone cancer centre (2week wait) or 48h wait for children
If x-ray unclear and symptoms persist = further imaging including MRI

Question 15

Where in the body are osteosarcomas likely to present? (which bones are they common in)

Answer 15

Knee

Distal femur & proximal tibia

Question 16

Where in the body are chondrosarcomas likely to present? (which bones are they common in)

Answer 16

Pelvis

Question 17

Where in the body are Giant Cell Tumours likely to present? (which bones are they common in)

Answer 17

Knee

Question 18

Where in the body is Ewing’s likely to present? (which bones are they common in)

Answer 18

ribs, pelvis, proximal femur, around the knee, feet.

Question 19

What are some primary cancers which commonly metastasise to bone? (5) Where is the most common site they metastasise to?

Answer 19

Breast
Lung
Kidney
Prostate
Thyroid
Most common site of metastasis if the spine.

Question 20

Describe what an osteoid osteoma is, most common age of presentation, does it affect more males or females? Where does it usually present?
How do they usually present? X ray finding?
Treatment?

Answer 20

Benign lesion in young patients typically 10-20 and more common in males.
Commonly found in the metaphysis of long bones (prox femur, tibia and spine)
Pain which is worse at night, swelling, limping, tenderness and made better with NSAIDs.
X ray shows small masses with a rim of reactive bone.
Treatment: conservative, imaging every 6 m and prognosis is good.

Question 21

Describe what an osteochondroma is, most common age of presentation, does it affect more males or females? Where does it usually present?
How do they usually present? X ray finding?
Treatment?

Answer 21

• Outgrowth from the metaphysis of long bones covered with a cartilaginous cap, grows away from growth plate and stops growing after puberty
• Appears in second decade of life (10-20y) and more common in males
• Presenting complaint: painless lump
• Can be associated with hereditary conditions such as multiple hereditary exostoses

Xray
- Shows pedunculated bony outgrowth from metaphysis pointing away from the joint

Management

• Most managed conservatively through serial radiological imaging every 4-6m
• If there is significant deformity or neurological symptoms or suspicion - may warrant surgery

Question 22

What is the most common benign tumour of bone?

Answer 22

Enchondromas

Question 23

Describe what an enchondroma is, most common age of presentation?
Where does it usually present?
How do they usually present? X ray finding?
Treatment?

Answer 23

• Most common benign tumour
• Arises from chondroblasts within the medullary cavity of the bones or from the cortical surface
• 20-50yr olds
• Long bones of hands, femur, humerus but can occur anywhere on skeleton
• Mostly asymptomatic, but can present as pathological fracture
• 1% chance of malignant change, 5% chance if mulitple

Multiple enchondromas

• Ollier’s disease: non hereditary, multiple, metaphyses of long bones, limb deformity
• Maffucci syndrome: non hereditary, multiple associate with haemangiomas

Xray

• Well circumscribed oval lucency with intact cortex
• Metaphyseal ‘popcorn’

Management

• Asymptomatic and small - observed
• Large or symptomatic - curettage or bone grafting

Question 24

Describe what a giant cell tumour is, most common age of presentation? Females or males more affected?
Where does it usually present?
How do they usually present? X ray finding?
Treatment?

Answer 24

Giant cell tumours arise from the multinucleated giant cells and stromal cells

• They are aggressive and potentially malignant
• Local recurrence and distant metastases
• Patients 20-30y
• More common in females, rare in children
• Usually affecting epiphyses of long bones (femur, proximal tibia, distal radius)
• Pain swelling limitation of joint movement
• Always get a biopsy

X ray
- Eccentric lytic areas giving ‘soap bubble’ appearance

Management

• Surgical resection potentially requiring bone grafting or reconstruction
• Curretage, washout, bone cement to fill the defect.
• Bisphosphonates

Question 25

Describe what fibrous dysplasia is, most common age of presentation? Females or males more affected?
Where does it usually present?
How do they usually present? X ray finding?
Treatment?

Answer 25

• Benign, slow growing
• Normal bone replaced by metastic woven bone + fibrous tissue
• Solitary 85%
• Can occur at any age, no gender predilection
• Often asymptomatic
• Always include fibrous dysplasia on a benign looking bone lesion

X ray
- Well circumscribed, diphyseal, ground glass appearance

Treatment

• Surgery - curretage, bone graft is symptomatic
• Medical - bisphosphonates

Question 26

What is the most common malignant primary bone tumour?

Answer 26

Osteosarcoma

Question 27

Describe what an osteosarcoma? Most common age of presentation? Females or males more affected?
Where does it usually present?
How do they usually present? X ray finding?
Treatment?

Answer 27

• Most common malignant primary bone tumour
• Bi modal age of onset, either 10-14 (more common) or >65 (typically those with Paget’s disease)
• Genetic conditions
  → Hereditary retinoblastoma and Li-Fraumeni syndrome
• Site
  → Metaphysis of the distal femur or proximal tibia (most common)
• Intramedullary osteosarcoma (high grade) - classic osteosarcoma
  → Most common type
  → Affects knee, proximal humerus, proximal femur
  → Children & young adults
  → 90% high grade and penetrate cortex early forming soft tissue mass
  → 10-20% have pulmonary mets
• Parosteal osteosarcoma (low grade)
• Periosteal osteosarcoma (high grade)
• Telengiectatic
• Associated with p53 mutation

X ray
- Medullary and cortical bone destruction periosteal reactions - codemans triangle, sunburst pattern

Diagnosis
- Tissue biopsy required

Treatment

• Bone cancer centre
• Aggressive surgical resection
• Systemic chemotherapy
• Metastasises to lung and bone
• Prognosis - depends on response to chemotherapy - 70% survive 5 years

Question 28

What is the second most common malignant primary bone tumour?

Answer 28

Chondrosarcoma

Question 29

Describe what a chondrosarcoma is? Most common age of presentation?
Where does it usually present?
Imaging findings?
Treatment?

Answer 29

Second most common primary bone tumour

• Occurs in those older than 40
• Chondrosarcomas are most commonly found in the pelvis followed by proximal femur, proximal humerus, distal femur and ribs.

CT / MRI
- Large unmineralised soft tissue mass associated with the lesion

Treatment

• Surgical excision
• Prognosis good with low grade tumours - 90% 5 yr survival

Question 30

What is Ewings sarcoma?
Who does it affect?
Presentation on patient?
X ray findings
Treatment

Answer 30

Small round cell tumour

• Arises from neural crest cells
• Occurs in children and young adults (rare in over 30s)
• Affects caucasians more commonly than afro-caribbeans (9:1), more common in males
• Painful and enlarging mass - tenderness and warmth (often initially mistaken for osteomyelitis)
• Aggressive
• Affects diaphysis of long bones - femur (most common), pelvis, distal tibia, prox humerus

X ray

• Lytic lesion with periosteal reactions
  
  • Destructive lesion - periosteum may be lifted off in multiple layers giving ‘onion skin’ appearance

Treatment

• Chemotherapy, radiotherapy and surgical excision or reconstruction
• Prognosis: 70% 3yr survival, lung mets -40% 3 yr survival

Question 31

What is a lipsarcoma

Answer 31

Malignant soft tissue tumour of adipose tissue

Question 32

What is a fibrosarcoma

Answer 32

Malignant soft tissue tumour of fibrous tissue

Question 33

What is a rhabdomyosarcoma

Answer 33

Malignant soft tissue tumour of muscle

Question 34

What is the most common soft tissue tumour in adults?

Who does it affect? What does it look like? What is the treatment for it?

Answer 34

Lipoma
Affects middle aged or elderly patients more often.
It is soft and slow growing, well circumscribed and lobular in arrangement

Treatment
- Do nothing or surgical excision if symptomatic

Question 35

What is the most common
malignant soft tissue tumour?
Who does it affect, what does it look like?
Treatment?

Answer 35

Liposarcoma
Occurs between 40-60
Common sites are lower limb, retroperitoneum
They are well differentiated and resemble a lipoma, they have high recurrence rates with no metastases
Poor prognosis if there are mixed cells and frequently metastasises

Treatment
- Most common is surgical removal of the tumour and sometimes radiotherapy or chemotherapy will follow.

Question 36

What is the most common malignant soft tissue tumour in children?

Answer 36

Rhabdomyosarcoma