Bone Tumours Flashcards
Where and when do primary and secondary ossification centres appear in long bone?
Primary - centre of the diaphysis during intrauterine life.
Secondary - each epiphyseal end sometime after birth.
How do bone tumours typically present?
- Pain
- Unexplained limb pain >1 month
- Pain at night - Swelling
- Pathological fracture
- Incidental finding - most primaries
What are the 3 forewarning signs of malignancy on X-ray?
- Cortical destruction
- Periosteal reaction
- Fuzzy line outside of cortex
- Also seen with # or infection - Zone of transition
- Sclerotic margin = narrow zone
- Diffuse margin - more aggressive
List 6 clinical indicators of malignancy?
- Pain (>1 month, at night)
- Swelling
- Tenderness
- Warmth
- X-ray changes (3 signs)
- Rapid growth of a lesion
What investigations are indicated if bone malignancy is suspected?
- X-ray
- Bone scans
- CT
- MRI
- ESR - raised
- ALP - raised
- Biopsy
Refer to specialist centre early
Recite the mnemonic for benign bone tumours
ABC FFG OO
Aneurysmal bone cyst Bone cyst - Simple, unicameral or solitary Chondroma - Aka endrochondroma Fibrous cortical defect - Aka nonossifying fibroma Fibrous dysplasia Giant cell tumour Osteochondroma Osteoid osteoma
Expansile cysts that usually affect under 30s. Patients present with pain. MRI shows multiple fluid levels.
Aneurysmal bone cyst (benign tumour)
What is the pathognomonic sign for aneurysmal bone cysts, as seen on MRI?
Multiple fluid levels
How are symptomatic aneurysmal bone cysts treated?
Curette out cyst and fill with bone graft.
In which bones and in whom do simple bone cysts most commonly occur?
Proximal humerus and femur.
Young patients.
Usually asymptomatic.
When might you see the ‘fallen fragment sign’?
Specific radiological sign for a unicameral bone cyst with pathological fracture. Part of the thinned cortex ‘falls’ into the fluid-filled cyst.
Differentiate between Ollier’s disease, Maffucci’s syndrome and metachondromatosis.
Multiple enchondromas present in 3 disorders: Ollier disease - Sporadic (more common) - Unilateral distribution Maffucci's syndrome - Sporadic - Associated with hemangiomas Metachondromatosis - Autosomal-dominant - Both multiple osteochondromas and enchondromas.
What are (endo)chrondromas and which bones are most commonly affected?
The most common benign tumours of hyaline cartilage
Commonest site: phalanges. Can affect other long bones.
A 43 year-old man presents with ongoing pain and swelling in his hands and feet. X-ray findings reveal cystic lesions of the phalanges. Which condition is it important to exclude?
Low-grade chondrosarcoma - may develop from benign cystic lesions (chondromas)
What is a nonossifying fibroma and how does it typically present?
Aka fibrous cortical defect.
- Benign defect of cortex
- Common: incidental finding on X-ray in 20% of children
- Nonpainful
- Usually affects metaphysis
- Usually spontaneously regress
- Rarely seen after age 30
Differentiate between monostotic and polystotic fibrous dysplasias
Fibrous dysplasia = areas of bone are replaced by fibrous tissue.
Monostotic = localised
- Solitary segment affected
- More common (70-80%)
- Unknown cause
- Incidental X-ray finding or presents as pathological # with pain
Polystotic = generalised
- 20-30%, several bones affected
- Presentation: progressive deformity (bending, enlargement), pain and pathological fracture
- X-ray: ground glass or smokey
- Elephant man?!
What is McCune-Albright syndrome?
A rare condition in which polyostotic fibrous dysplasia occurs in association with café au lait spots and (in females) precocious puberty (endocrinopathies).
In whom and in which bone(s) are giant cell tumours most commonly seen?
Occur in young adults (always after fusion of growth plate) usually around knee (lower femur or upper tibia) and always abut the articular surface.
Which is the commonest tumour of the bone?
Osteochondroma - aka “exostosis”, a cartilage-capped outgrowth. Arise from metaphysis, especially about knee. M>F (3:1)
A patient presents with a bony lump. X-ray shows a cauliflower-shaped projection from bone that is smaller than the size to touch. What is the most likely diagnosis?
Osteochondroma - if symptomatic, excise tumour.
Chondrosarcoma - if it changes in size after skeletal maturity.
A 20 year old patient presents with ongoing leg pain which is relieved by aspirin. X-ray shows a small radiolucent area surrounded by dense sclerosis which appears as a hot spot on a bone scan. What is the most likely diagnosis and how would you treat?
Osteoid osteoma - a benign tumour (
How does an osteoblastoma differ to an osteoid osteoma?
An uncommon primary bone tumour with clinical and histological similarities to osteoid osteoma, but larger (2-6 cm). Usually benign and related to spine.
In whom do osteosarcomas most commonly occur?
Males > females (3:1)
Primary: adolescents (under 20)
Secondary: over 50s (due to Paget’s disease)
What is the main symptom of osteosarcoma?
Pain, especially nocturnal
+/- local tenderness
