7- Bone cancers

Question 1

Bone cancers background

Answer 1

Metastatic bone cancer is much more common than Primary (osteosarcoma, chondrosarcoma, fibroscarcoma, Ewings)

Primary cancers:
- Rare
- Start in the bone known as bone sarcomas
- Sarcomas are cancers which start in the bone, muscle, fibrous tissue, blood vessels, fat tissue and develop anywhere in the body

Question 2

types of primary bone cancer

Answer 2

Primary tumours arise from cells which constitute the bone and can divided into benign and malignant types

Bone forming tissues: Osteosarcoma
Cartilage forming tissues : Chondrosarcoma
Fibrous tissue: Fibrosarcoma
Marrow tumours: Ewings, Myeloma

Question 3

Bone metastasis

Answer 3

Most common primary sites:

• Breast cancer (lytic)
• Prostate (sclerotic)
• Lung cancer (lytic)

Most common sight for bony metastases: the Spine

Management:

• tends to be palliative
• dexamethasone for MSCC
• radiotherapy
• prophylactic nailing of certain long bones if pathological fractures likely

Question 4

Osteosarcoma
Background

Answer 4

• Most common primary bone cancer in children
• Bimodal age distribution
• Location:
  1) distal femur
  2) proximal tibia

Question 5

Types of osteosarcoma

Answer 5

depend on how well-differentiated the cells are when oncogenic events occur
- Osteoblastic- most highly differentiated
- Chrondroblastic
- Fibroblastic- least highly differentiated

Question 6

Risk factors for osteosarcoma

Answer 6

• 10-20yo
• Usually tall for age
• Males>females
• p53 mutation (Li-Fraumeni syndrome)
• RB1 mutation (familial retinoblastoma)
• Prior radiation therapy or chemotherapy
• Pagets/ osteochondromas

Question 7

pathophysiology of osteosarcoma

Answer 7

Mutation occurs in rapidly dividing osteoblasts e.g. pubertal growth spurt

Question 8

presentation of osteosarcoma

Answer 8

• Persistent bone pain
• Worse at night
• May wake them up
• Others:
  o Bone swelling
  o Palpable mass
  o Restricted joint movement
• Weight loss, fatigue, headache

Question 9

Red flags for osteosarcoma

Answer 9

• Bone pain that persists and gets worse
• Wakes up from sleep
• Swelling and redness over bone
• Weak bone that fractures easily

Diffferentials: osteomyelitis or multiple myeloma

Question 10

investigations for osteosarcoma

Answer 10

VERY URGENT XRAY within 48 hours
If Xray suggest sarcoma -> VERY URGENT SPECIALIST ASSESSMENT within 48 hours

BLOOD TESTS
- Raised alkaline phosphatase (ALP)

Other investigations
- MRI
- Bone scan
- PET
- Bone biopsy
E.g. needle biopsy or surgical biopsy during tumour excision

Question 11

x-ray osteosarcoma

Answer 11

• Poorly defined lesion in bone, with destruction of normal bone and ‘fluffy’ appearance
• Periosteal reaction (irritation of bone lining)- “sun-burst” appearance
• Soft tissue mass

Question 12

management of osteosarcoma

Answer 12

• Aggressive surgical resection of lesion = LIMB AMPUTATION
• Adjuvant chemotherapy improves outcomes

MDT support
o Paediatric oncologists and surgeons
o Specialist nurses
o Physiotherapy
o OT
o Psychology
o Dietician
o Prosthetics and orthotics
o SS

Question 13

complications of osteosarcoma

Answer 13

• Leading cause of death in the young
• Pathological fractures
• Metastatic disease

Question 14

Ewings sarcoma
Background

Answer 14

• Second most common primary bone cancer in children
• Paediatric malingnancy
• Malignancy of neural crest cell
• Most commonly occurs in bone, rare cases in soft tissue (extraosseous ewings)
• Requires aggressive treatment
• Flat bones
  o Tibia
  o Fibula
  o Knee joint
  o Femur
  o Pelvis
  o Ribs

Question 15

risk factors for ewings sarcoma

Answer 15

• Males
• 10-20yo
• Caucasian
• Rare in those older than 30yo

Question 16

Pathophysiology for Ewings sarcoma

Answer 16

• Ewing sarcoma is a small, round blue cell tumour
• Due to uncontrolled cell turnover and tumour formation

Question 17

Presentation Ewings sarcoma

Answer 17

• Bone pain: can be misinterpreted as growing pain or sports injuries
• Restricted movement of joint
• Fatigue, weight loss, fever
• Fracture susceptibility
• Red flags
  o Unexplained bony lump

Question 18

investigations for Ewings sarcoma

Answer 18

URGENT X-RAY WITHIN 48 HOURS
If x-ray suggest cancer- specialist assessment within 48 hours

Bloods: FBC, UandE, LFTS, ESR< CRP, ALP and bone profile
Anaemia, leucotosis, elevated WBC, elevated ESR, elevated LDH, elevated ALP and elevated CRP

Imaging
- Initial XRAY
- MRI, CT, PET- staging

Bone biopsy- definitive

Question 19

Ewings sarcoma x-ray

Answer 19

Lytic lesion with periosteal reactions , producing layers of reactive bone (periosteal reaction) leading to characteristic “onion skin” appearance.

Question 20

management of Ewings sarcoma

Answer 20

Needs to be aggressive: chemo, surgery radiotherapy
Chemotherapy
- Shrinks tumour prior to surgery and destroy remaining tumour cells which may have spread from primary site

Surgery
- Limb sparing surgery
–>Resection of tumour and either a metal implant or autologous bone graft
- If tumour spread to widely- amputation performed

Radiotherapy
- Not used in every patient
- Can be used to shrink tumour prior to surgery

Question 21

Complications of Ewings sarcoma

Answer 21

• Metastatic disease
  o Lungs
  o Bones
  o Bone marrow
• Recurrence

Question 22

Chondrosarcoma
Background

Answer 22

• Most common in adulthood
• Starts in the early forms of cartilage cells
• Can start anywhere there is cartilage
• Most commonly Axial skeleton
  o Pelvis
  o Legs
  o Arms/knee
  o But also: trachea, larynx, chest wall, shoulder blades, ribs or skull)
• Can arise from chondromas
• Locally aggressive

Question 23

Risk factors chondrosarcoma

Answer 23

• Rare in people younger than 20
• Risk goes up as people get older
• Enchodromas – a type of benign bone tumour that begins from cartilage and usually affects hands

Question 24

presentation of chondrosarcoma

Answer 24

Presentation
- Large mass on affected bone
- Feeling of pressure around mass
- Pain that increases gradually over time
- Pain usually worse at night and may be relieved by taking NSADIs
- Local swelling

Question 25

Investigations for chondrosarcoma

Answer 25

- Xray- popcorn calcification (lytic lesion) - CT - MRI - Biopsy - PET

Question 26

grading of chondrosarcoma

Answer 26

Grading * Low-grade (grade I) chondrosarcomas, also called atypical cartilaginous tumors, tend to grow the slowest and are very unlikely to spread. * Intermediate-grade (grade II) chondrosarcomas are slightly more likely to spread. * High-grade (grade III) chondrosarcomas are the most likely to spread.

Question 27

management of chondrosarcoma

Answer 27

Management * Surgery. Removal of the tumor. If the tumor is on an arm or leg, the surgeon will try to save the limb. In some cases, amputation might be needed. * Physical therapy. This treatment helps to regain strength and use of the affected area after surgery * Tend to be chemotherapy and radiotherapy resistant

Question 28

High-grade undifferentiated pleomorphic sarcoma (UPS) of bone

Answer 28

This cancer was previously known as malignant fibrous histiocytoma (MFH) of bone. Undifferentiated pleomorphic sarcoma (UPS) most often starts in soft tissues (connective tissues such as ligaments, tendons, fat, and muscle). It's rare in bones, but when it does occur, it usually affects the legs (often around the knees) or arms. This cancer most often occurs in elderly and middle-aged adults. It's rare in children. It tends to grow locally, but sometimes it can spread to distant parts of the body, like the lungs.

Question 29

Fibrosarcoma of bone

Answer 29

Fibrosarcoma is another type of cancer that develops more often in soft tissues than it does in bones. It usually occurs in middle-aged adults. Bones in the legs, arms, and jaw are most often affected.

Question 30

Giant cell tumor of bone

Answer 30

This type of primary bone tumor can be either benign (not cancer) or malignant. The benign form is more common. These tumors are most common in people in their 20s and 30s. Giant cell bone tumors typically affect the legs (usually near the knees) or arms. They don’t often spread to distant parts of the body, but after surgery they can come back (even more than once) in the place where they started. With each recurrence, the tumor becomes a bit more likely to spread to other parts of the body (most often to the lungs). Rarely, a malignant giant cell bone tumor spreads to other parts of the body without first recurring locally.

Question 31

Chordoma

Answer 31

This uncommon type of bone tumor occurs in the bones of the spine, most often at the bottom of the spine (sacrum) or the base of the skull. It develops most often in adults older than 30. It's about twice as common in men as in women. Rarely it can develop in children, as well. Chordomas tend to grow slowly and often do not spread to other parts of the body. They often come back in the same area if they are not removed completely. If they do spread, they most often go to the lymph nodes, lungs, or liver.

Question 32

summary of primary bone cancer

Answer 32