Malignant Bone Tumours Flashcards
1
Q
What are the risk factor for malignant primary bone tumours?
A
- Previous radiotherapy
- Predisposing conditions: Paget’s, fibrous dysplasia, multiple enchondromas
- Genetic causes: Li Fraumeni syndrome (p53), familial retinoblastoma (RBI)
2
Q
What is the clinical presentation of malignant primary bone tumours?
A
- Presentation is often late in the disease
- Higher index of suspicion in younger patients (10-30 years)
- Persistent, increasing pain
- Usually not associated with movement
- Well localised
- Worse at night
- Not uncommonly misdiagnosed for muscular pains - any unexplained persistent skeletal pain/red flags should be further investigated
- Pathological fracture
- Swelling and erythema over joint (especially in Ewing’s sarcoma)
- Palpable mass
3
Q
What is multiple myeloma?
A
- Malignant disease of the plasma cells of the bone marrow
- Commonest primary tumour of bone
4
Q
What is the clinical presentation of multiple myeloma?
A
- Generally affects elderly patients
- 4 main features are hypercalcaemia, anaemia, renal impairment and bone pain
5
Q
What is osteosarcoma?
A
- Malignant tumour which produces bone
- Most common primary sarcoma of bone
- Metastatic spread is usually haematogenous but can be lymphatic
6
Q
What is the clinical presentation of osteosarcoma?
A
- Most cases seen in adolescence and early adulthood
- 2nd peak in the elderly associated with Paget’s
- 60% involve the bones around the knee (distal femur/proximal tibia), other sites include proximal femur, proximal humerus and pelvis
- 10-20% of patients have pulmonary metastases at diagnosis - impacts survival
7
Q
What is chondrosarcoma?
A
- Cartilage producing primary bone tumour - malignancy of chondrocytes
- Less common and less aggressive than osteosarcoma (generally - can be aggressive)
- Majority arise de novo, few arise from benign lesions (enchondroma, osteochondroma)
- Prognosis dependent on histological grade - majority are low grade
- Can be very large and are slow to metastasize
8
Q
What is the clinical presentation of chondrosarcoma?
A
- Tends to be found in the older age group - mean age 45
- Tend to be found in the pelvis or proximal femur
9
Q
What is Fibrosarcoma?
A
- Fibrous malignant primary bone tumours which tend to occur in abnormal bone e.g. bone infarct, post radiation
- Fibrosarcoma tends to affect adolescents/YAs
10
Q
What is Ewing’s sarcoma?
A
- Primary bone tumour of the endothelial cells of the bone marrow
- 2nd commonest malignant bone tumour in children
- Characterised by loss of bone (lysis)
11
Q
What is the clinical presentation of Ewings sarcoma?
A
- Affects young people 5-25 years of age, most common age 10-20
- Hot, swollen, tender joint or limb with raised inflammatory markers - can mimic infection
- Usually found in diaphysis of long bones - distal femur, proximal tibia
12
Q
What are the investigations for malignant primary bone tumours?
A
- X-ray
- Biopsy required for histological diagnosis and grading before surgery
- Staging - bone scan, CT, MRI
13
Q
What would an x-ray show in malignant primary bone tumours?
A
- aggressive and destructive signs including cortical destruction, a periosteal reaction, new bone formation (sclerosis and lysis), reactive cortical thickening (chondrosarcoma) and extension into the surrounding soft tissue envelope
- AP and lateral including joint above and below
- Bony lesions may not show up on x-rays until more than 50% of the cortical bone is lost - if x-ray normal but clinical suspicion is high perform further imaging
14
Q
What is the management for malignant primary bone tumours?
A
- Surgery - removal of tumour and surrounding tissue, with joint reconstruction
- Adjuvant chemotherapy/radiotherapy used if appropriate
- Neo-adjuvant chemotherapy can improve survival
15
Q
What margin is required for excision of a malignant primary bone tumour?
A
Typically margin of 3-4cm of bone and a cuff of normal muscle all around
