Musculoskeletal tumours are abnormal growths that originate in the bone or soft tissues such as muscle, cartilage, fat, or fibrous tissue. They may be benign (non-cancerous) or malignant (cancerous). Although relatively rare, they require timely recognition, as some can be life-threatening or severely disabling.
- Malignant tumours from connective tissue are called sarcomas.
- Tumours from epithelial tissues are termed carcinomas, and are not included here.
Benign vs Malignant Bone Tumours
| Feature | Benign Tumours | Malignant Tumours |
|---|---|---|
| Growth rate | Slow | Rapid |
| Spread | Localised | May spread (metastasize) |
| Pain | Usually painless | Often painful, worse at night |
| Prognosis | Excellent | Variable – depends on type & stage |
| Examples | Osteoid osteoma, Chondroma | Osteosarcoma, Ewing’s sarcoma |
Causes and Risk Factors
- Genetic mutations (e.g., Li-Fraumeni syndrome, RB gene mutation)
- Pre-existing bone lesions (e.g., Paget's disease)
- Radiation exposure
- Chronic inflammation or trauma
- Infections (e.g., tuberculosis, leading to chronic osteomyelitis)
- Age group:
- Children and adolescents: Ewing’s sarcoma, osteosarcoma
- Older adults: Chondrosarcoma, multiple myeloma
Clinical Features of Bone Tumours
- Dull aching bone pain, often worse at night
- Swelling or visible lump
- Limp or decreased range of motion
- Pathological fracture
- Symptoms of compression if near nerves
- Fever, weight loss, or fatigue (in systemic malignancy)
Investigations and Diagnosis
Imaging
- X-ray: Initial test – look for lytic or sclerotic lesions, Codman's triangle, sunburst pattern.
- CT scan: Best for cortical bone involvement.
- MRI: Best for marrow and soft tissue extension.
- Bone scan/PET-CT: Detect metastasis or multiple lesions.
Biopsy
- Needle biopsy (core or fine-needle aspiration)
- Incisional biopsy (for deeper lesions)
Important: Biopsy should be done after imaging and ideally in a centre where definitive surgery is planned.
Staging of Bone Tumours
| Stage | Grade | Spread |
|---|---|---|
| I | Low grade | Localised |
| II | High grade | Localised |
| III | High grade | Regional lymph nodes |
| IV | High grade | Distant metastasis |
Classification by Cell Origin
| Tissue Type | Benign | Malignant |
|---|---|---|
| Fibroblast | Bone cysts | Malignant fibrous histiocytoma (MFH) |
| Chondrocyte | Chondroma | Chondrosarcoma |
| Bone cells | Osteoid osteoma, Osteoblastoma | Osteosarcoma |
| Marrow/Unknown | Myeloma, lymphoma | Giant cell tumour, Ewing’s sarcoma |
| Soft tissues | Lipoma, Neurofibroma, Leiomyoma | Liposarcoma, Rhabdomyosarcoma |
Common Musculoskeletal Tumours
Chondroma and Chondrosarcoma
- Chondroma: Benign cartilage tumour found in hands, feet, ribs
- Chondrosarcoma: Malignant tumour of cartilage, affects pelvis, ribs, femur
Often arises from pre-existing chondromas
Osteochondroma
- Benign tumour from metaphyseal bone
- Most common benign bone tumour in children
- May compress vessels/nerves or undergo malignant change
Osteoid Osteoma
- Small, painful benign tumour often in femur or tibia
- Nocturnal pain relieved by NSAIDs
- X-ray: radiolucent nidus with reactive sclerosis
Osteoblastoma
- Similar to osteoid osteoma but larger and not relieved by NSAIDs
Osteosarcoma
- Most common primary malignant bone tumour
- Affects metaphysis of long bones – knee, humerus
- Sunburst pattern on X-ray, Codman’s triangle
- Common in ages 10–20
- Rx: Surgery + neoadjuvant chemotherapy
Ewing’s Sarcoma
- Second most common malignant bone tumour in children
- Diaphysis of long bones, pelvis
- Onion-skin periosteal reaction
- May present with fever, mimics infection
- Rx: Chemotherapy, surgery, radiotherapy
Multiple Myeloma
- Malignancy of plasma cells in bone marrow
- Common in older adults
- Multiple punched-out lesions on X-ray
- Symptoms: bone pain, anemia, renal failure
- Rx: Chemotherapy ± stem cell transplant
Soft Tissue Tumours
- Benign: Lipoma, haemangioma, neurofibroma
- Malignant: Liposarcoma, rhabdomyosarcoma, synovial sarcoma, leiomyosarcoma
- Usually painless masses
- Require biopsy and imaging for diagnosis
Treatment and Management
Surgery
- Aim: complete resection with negative margins
- Limb-sparing is preferred over amputation
- Reconstruction using prosthesis or grafts
Chemotherapy
- Neoadjuvant (before surgery) and adjuvant (after surgery)
- Common for osteosarcoma and Ewing’s sarcoma
Radiotherapy
- Mainly for Ewing’s sarcoma or inoperable tumours
Rehabilitation
- Critical for restoring function and improving quality of life
- Physiotherapy, prosthetic support, counselling
Prognosis and Survival Rates
| Tumour Type | 5-Year Survival |
|---|---|
| Osteosarcoma | ~70% (non-metastatic) |
| Ewing’s Sarcoma | ~60–70% (localized) |
| Chondrosarcoma | Variable (depending on grade) |
| Multiple Myeloma | ~35% |
FAQs on Musculoskeletal Tumours
Q. Are all bone tumours cancerous?
No, many bone tumours like osteochondromas and osteoid osteomas are benign.
Q. Is limb amputation always required?
No, limb-sparing surgeries are possible in most cases today.
Q. How do you differentiate between benign and malignant bone tumours?
Via biopsy, imaging features (lytic, destructive lesions), and clinical behaviour (pain, growth, systemic signs).
Conclusion
Musculoskeletal tumours, though rare, pose significant diagnostic and management challenges. With advances in imaging, surgery, and chemotherapy, many patients now achieve long-term survival and functional recovery. Early diagnosis, multidisciplinary management, and patient-centric care are key pillars of treatment success.
Stay informed. Stay vigilant. When in doubt, investigate that swelling or bone pain—it could be more than just a sprain.
