Advanced Bone Tumor Surgery & Limb Preservation

Understanding Bone Tumors in the Indian Context

Bone tumors—abnormal growths within skeletal tissue—range from benign (non-cancerous) to malignant (cancerous). At Ajuda Hospitals, our musculoskeletal oncology program combines orthopaedic oncologists, medical oncologists, and reconstructive surgeons to deliver limb-salvage surgery, advanced reconstruction, and coordinated chemotherapy/radiation for optimal outcomes.

Classification

Benign Bone Tumors (90% of bone tumors):

• Osteochondroma: Most common; bony projection with cartilage cap; adolescents; usually asymptomatic
• Enchondroma: Cartilage tumor within bone; hands/feet; pathological fracture risk
• Giant Cell Tumor: Locally aggressive; epiphyseal location; adults 20-40 yrs; 10-20% recurrence post-curettage
• Aneurysmal Bone Cyst: Blood-filled cystic lesion; adolescents; expansile, destructive
• Osteoid Osteoma: Small nidus (<2 cm); night pain relieved by aspirin; adolescents/young adults

Malignant Bone Tumors (Primary):

• Osteosarcoma: Most common primary bone cancer; adolescents (growth spurt); knee (distal femur, proximal tibia); requires neoadjuvant chemo + wide resection
• Ewing Sarcoma: Second most common pediatric bone cancer; diaphyseal/flat bones (pelvis, ribs); highly malignant; chemosensitive
• Chondrosarcoma: Cartilage malignancy; adults >40 yrs; pelvis, proximal femur; chemoresistant—surgery only

Metastatic Bone Tumors (Most Common):

• Adults >50 yrs: Breast, lung, prostate, kidney, thyroid metastases to bone
• Osteolytic (breast, lung, kidney), osteoblastic (prostate), or mixed
• Palliative management: Radiation, bisphosphonates, prophylactic fixation for impending fracture

India-specific considerations: Delayed presentation (tumors >10 cm at diagnosis), limited access to pediatric oncology centers, financial barriers to prolonged chemotherapy. Our program provides comprehensive care with insurance navigation and subsidized treatment options.

When to Consult Our Bone Tumor Specialists

Red Flags for Malignancy:

• Pain Pattern: Night pain, rest pain (not relieved by position change), worsening pain despite NSAIDs
• Constitutional Symptoms: Fever, weight loss, fatigue, night sweats
• Age: Adolescents 10-25 (osteosarcoma, Ewing), older adults >40 (chondrosarcoma, metastases)
• Location: Metaphyseal (knee, shoulder, wrist) for osteosarcoma; diaphyseal (femur, tibia shaft) for Ewing; pelvis for chondrosarcoma
• X-ray Features: Aggressive periosteal reaction (Codman triangle, sunburst), moth-eaten or permeative bone destruction, soft tissue mass

Do NOT Delay: Refer to bone tumor specialist within 2-4 weeks of abnormal X-ray or persistent symptoms. Delayed diagnosis worsens prognosis—tumors >10 cm, skip lesions, or metastases significantly reduce survival.

Our Diagnostic Approach

Clinical Assessment & History

Patient Factors:

• Age: Osteosarcoma 10-25, Ewing 5-20, giant cell tumor 20-40, chondrosarcoma >40, metastases >50
• Location: Knee region (osteosarcoma), pelvis/diaphysis (Ewing), hands/feet (enchondroma), spine (metastases)
• Duration: Weeks-months = malignancy concern; years = likely benign
• Trauma History: Pathological fracture (fracture through tumor with minimal trauma) indicates weakened bone

Pain Characteristics:

• Night Pain: Classic for osteoid osteoma, malignant tumors
• Activity Pain: Benign tumors, stress fractures
• Rest Pain: Malignancy until proven otherwise

Systemic Symptoms:

• Fever, weight loss, fatigue = Ewing sarcoma or metastases
• No systemic symptoms = osteosarcoma, chondrosarcoma (local disease)

Imaging Studies

Plain X-rays (First-Line):

Benign Features:

• Well-defined borders, sclerotic rim
• Geographic bone destruction (single large lytic area)
• No soft tissue mass
• Slow growth on serial films

Malignant Features:

• Ill-defined borders, wide zone of transition
• Moth-eaten (multiple small holes) or permeative (diffuse infiltration) bone destruction
• Aggressive periosteal reaction: Codman triangle (periosteum lifted off bone), sunburst pattern (radiating ossification), onion-skin (layered periosteal response)
• Soft tissue mass extending beyond bone

MRI (Gold Standard for Local Staging):

• Tumor Extent: Size, compartment involvement (intra- vs extra-compartmental)
• Neurovascular Relationship: Can tumor be resected without sacrificing major artery/nerve?
• Skip Lesions: Satellite tumor deposits in same bone—changes prognosis, requires longer resection
• Joint Involvement: Intra-articular extension necessitates joint resection
• Marrow Edema: Reactive edema vs true tumor infiltration (helps plan margins)

CT Chest (Mandatory for Malignant Tumors):

• Detect lung metastases (most common metastatic site for bone sarcomas)
• Present in 10-20% osteosarcoma at diagnosis
• Prognosis: Localized disease 70% 5-year survival; metastatic disease 20-30%

Bone Scan or PET-CT:

• Whole-body screening for multifocal lesions (metastatic disease, Ewing sarcoma, multiple myeloma)
• Skip lesions in same bone
• Synchronous primary tumors (rare)

CT Chest/Abdomen/Pelvis (If Metastatic Suspected):

• Identify primary tumor if bone metastasis (breast, lung, prostate, kidney, thyroid)
• Stage metastatic disease burden

Biopsy & Histopathology

Biopsy Principles (Critical—Improper Biopsy Compromises Limb Salvage):

Who Performs Biopsy: Orthopaedic oncologist who will perform definitive surgery. Biopsy tract must be planned for excision with tumor—improper tract placement can contaminate tissue planes, converting limb-salvage case to amputation.

Biopsy Technique:

• Core Needle Biopsy (Preferred): 11-14 gauge Tru-Cut needle; 3-5 cores; 80-90% diagnostic accuracy; minimal contamination
• Open Incisional Biopsy: If needle biopsy non-diagnostic; small longitudinal incision (not transverse—compromises resection); frozen section confirms adequate tissue; meticulous hemostasis (hematoma spreads tumor cells)

Pathology Evaluation:

• Histology: Cell type (osteoblastic, chondroblastic, fibroblastic, small round blue cell)
• Grade: Low-grade (well-differentiated, <5 mitoses/10 HPF, <10% necrosis) vs high-grade (poorly differentiated, >10 mitoses, >50% necrosis)
• Immunohistochemistry: CD99 for Ewing, S100 for chondrosarcoma, AE1/AE3 for metastatic carcinoma
• Genetic Testing: EWSR1 fusion (Ewing sarcoma), MDM2 amplification (dedifferentiated liposarcoma), IDH1/2 mutations (chondrosarcoma)

Multidisciplinary Tumor Board

Team Members: Orthopaedic oncologist, medical oncologist, radiation oncologist, radiologist, pathologist, physiotherapist, psychologist

Discussion Points:

• Diagnosis Confirmation: Radiology-pathology correlation (diagnosis must fit imaging pattern)
• Staging: AJCC TNM staging, Enneking surgical staging (intra/extra-compartmental, grade, metastases)
• Treatment Plan: Neoadjuvant chemotherapy? Surgical margins feasible (wide vs marginal vs amputation)? Reconstruction option (endoprosthesis, allograft, rotationplasty)?
• Adjuvant Therapy: Chemotherapy protocol, radiation for positive margins or Ewing sarcoma

Treatment Pathways

Benign Bone Tumors

Observation (Selected Cases)

Indications: Asymptomatic small lesions (enchondroma <3 cm, small osteochondroma)

Surveillance: X-rays every 6-12 months for 2 years, then annually. Growth or pain prompts intervention.

Intralesional Curettage + Bone Grafting

Procedure:

1. Cortical window created with saw/osteotome
2. Curettage (scrape tumor from cavity with curettes)
3. High-speed burr extends curettage 5mm beyond visible tumor (mechanical adjuvant)
4. Chemical adjuvants: Phenol, hydrogen peroxide, liquid nitrogen, or argon beam coagulation (kill microscopic residual tumor cells)
5. Pack cavity with cancellous autograft (iliac crest), allograft, or bone substitute (calcium phosphate, calcium sulfate)
6. Alternatively, fill with PMMA cement (immediate stability, no graft harvest morbidity)

Outcomes: 95% cure for enchondroma, osteoblastoma, aneurysmal bone cyst. Giant cell tumor 10-20% recurrence (more aggressive)—denosumab (RANKL inhibitor) reduces recurrence in some protocols.

Marginal Excision

Osteochondroma: Excise entire lesion including cartilage cap and overlying periosteal sleeve (recurrence if cap remnants left). Indicated if symptomatic (pain, neurovascular compression, cosmetic) or rapidly enlarging (malignant transformation <1%).

Malignant Bone Tumors (Primary)

Neoadjuvant Chemotherapy

Osteosarcoma & Ewing Sarcoma (Chemosensitive):

• MAP Protocol (Osteosarcoma): Methotrexate (high-dose with leucovorin rescue), Doxorubicin (Adriamycin), Cisplatin (Platinol). 8-10 weeks pre-surgery.
• VDC/IE Protocol (Ewing): Vincristine, Doxorubicin, Cyclophosphamide alternating with Ifosfamide, Etoposide. 12 weeks pre-surgery.

Benefits:

• Treats micrometastases early
• Shrinks tumor—easier resection, lower positive margin rate
• Assesses chemosensitivity—tumor necrosis >90% ("good response") predicts better survival

Timing: Surgery at Week 10-12 for osteosarcoma; Week 12 for Ewing. Delays >2 weeks after chemo completion increase recurrence risk.

Wide Resection

Enneking Margins:

• Wide: Remove tumor + entire reactive zone + cuff of normal tissue (2-3 cm margin). En-bloc resection (tumor never exposed). Goal for high-grade sarcomas.
• Marginal: Dissection through reactive zone—higher local recurrence but preserves more tissue. Acceptable for low-grade tumors or if wide margin sacrifices major neurovascular structure.
• Intralesional: Tumor violated/piecemeal removal—NOT acceptable for malignant tumors (except palliative debulking for metastases).

Procedure:

1. Biopsy tract excised with specimen
2. Osteotomy planes planned 2-3 cm beyond tumor on MRI (intramedullary involvement extends beyond visible tumor—undershoot margins = recurrence)
3. Soft tissue dissection maintaining envelope around tumor (extraperiosteal for bone tumors)
4. Neurovascular structures preserved if not encased; sacrifice and reconstruct (vein graft, nerve graft) if necessary
5. Frozen section confirms negative margins intra-operatively

Reconstruction follows immediately (see below).

Limb Salvage Reconstruction

Endoprosthetic Reconstruction (Modular Mega-Prosthesis):

• Custom or modular implants replace resected bone + joint
• Distal femur, proximal tibia, proximal humerus most common
• Tumor prostheses: Rotating hinge knee (greater constraint than standard TKR), cemented long stems for diaphyseal fixation, compressive osseointegration surface promotes bone ingrowth
• Growing prostheses for children: MUTARS (externally lengthened via magnet every 6 months without surgery) or Stanmore (require surgery for lengthening)

Advantages: Immediate stability, early weight-bearing, shorter rehab (3-6 months). Disadvantages: Infection 5-10%, aseptic loosening 20% at 10 years, polyethylene wear, not biological (no bone stock regeneration).

Allograft Reconstruction:

• Osteoarticular allograft (includes joint surface) or intercalary allograft (diaphyseal segment only)
• Attached with plate or intramedullary nail
• Allows ligament, tendon reattachment to graft—better soft tissue envelope than smooth prosthesis
• Biologic—remodels over years, preserves bone stock for future revisions

Advantages: Biologic solution, better soft tissue attachment, no implant wear. Disadvantages: Union time 6-12 months (protected weight-bearing), fracture risk 15-20%, infection 5%, disease transmission (rare with modern screening).

Rotationplasty (Van Nes Procedure):

• Distal femur osteosarcoma in children/adolescents
• Remove tumor + knee + proximal tibia; rotate tibia 180°; anastomose vessels/nerves; attach tibia to femur (ankle becomes "neo-knee")
• Prosthetic below-knee limb fits over rotated foot
• Ankle dorsiflexion = prosthetic knee flexion; ankle plantarflexion = knee extension

Advantages: Superior function vs above-knee amputation (90% return to sports), biological reconstruction, grows with child. Disadvantages: Cosmetically challenging (foot points backward), psychological acceptance, not suitable if tibial nerve involved by tumor.

Vascularized Fibula Graft:

• Free fibula flap (fibular artery, vein harvest with bone) for large intercalary defects
• Advantages: Vascularized bone heals faster, hypertrophies over time, biological
• Disadvantages: Technically demanding (microvascular anastomosis), donor site morbidity, stress fracture risk first 1-2 years

Amputation (10% Cases)

Indications:

• Neurovascular involvement precluding resection (femoral artery/sciatic nerve encasement)
• Pathological fracture with extensive soft tissue contamination
• Infection after prior limb-salvage attempt
• Non-functional limb post-resection (e.g., foot/ankle tumor requiring below-knee amputation vs limb salvage leaving flail ankle—amputation provides better function)
• Patient preference

Level:

• Above-knee amputation (AKA): If tumor proximal tibia, distal femur
• Below-knee amputation (BKA): If tumor ankle/hindfoot; preserves knee—much better function
• Hemipelvectomy: Pelvic sarcomas not amenable to internal hemipelvectomy (resection + reconstruction)

Prosthetic Rehabilitation: Modern prosthetics (microprocessor knees, energy-storing feet) provide good function—can walk, stairs, drive. Psychological support critical.

Adjuvant Chemotherapy

Osteosarcoma: Continue MAP post-surgery for total 9-12 months. If poor response to neoadjuvant chemo (tumor necrosis <90%), consider alternative agents (ifosfamide, etoposide) but outcomes worse.

Ewing Sarcoma: Continue VDC/IE for total 12 months (48-54 weeks). Radiation therapy 50-55 Gy to tumor bed if positive margins or initially unresectable tumor (neoadjuvant chemo shrinks, then surgery).

Chondrosarcoma: Chemoresistant—surgery only. No role for chemo unless dedifferentiated chondrosarcoma (high-grade component).

Metastatic Bone Disease (Palliative Management)

Goals: Pain relief, prevent pathological fracture, maintain mobility, prolong survival (in selected patients).

Radiation Therapy: 8 Gy single fraction or 20-30 Gy fractionated. Pain relief in 70-80% within 2-4 weeks. Does NOT restore bone strength—fracture risk persists if >50% cortical destruction.

Prophylactic Fixation: If impending fracture (>50% cortical destruction, >2.5 cm lytic lesion in weight-bearing bone, persistent pain despite radiation). Intramedullary nail or plate fixation + PMMA cement augmentation. Fix BEFORE fracture occurs—easier surgery, faster recovery than after fracture.

Vertebroplasty/Kyphoplasty: Cement injection into collapsed vertebra (compression fracture from metastases). Immediate pain relief in 70-80%. Risk: Cement leak into spinal canal (rare, serious).

Bisphosphonates/Denosumab: Reduce skeletal-related events (fractures, spinal cord compression, hypercalcemia). Monthly IV zoledronic acid or SC denosumab. Start at time of bone metastases diagnosis.

Systemic Therapy: Hormone therapy (prostate, breast), targeted therapy (renal cell), immunotherapy—treat underlying cancer. Bone metastases can remain stable years with effective systemic therapy.

Technology & Innovation

3D-Printed Custom Implants

Patient-Specific Implants: CT scan → 3D model → design custom titanium implant matching exact anatomy.

Applications: Pelvis (complex 3D anatomy not amenable to standard prostheses), scapula, spine, mandible.

Benefits:

• Perfect anatomical fit—better stability, lower dislocation rate
• Reduced operative time (2 hours less vs intra-op contouring)
• Porous surfaces (lattice structures) promote osseointegration

Challenges: 6-8 week manufacturing delay, cost (₹5-8 lakh vs ₹2-3 lakh standard implant), cannot adjust intra-operatively if tumor size misjudged.

Computer Navigation for Margin Control

How It Works: Intra-operative CT + infrared tracking guides osteotomy saws in real-time. Surgeon visualizes resection plane on 3D model—ensures planned 2 cm margin achieved throughout.

Benefits:

• Reduces positive margin rate from 15-20% to <5%
• Preserves maximum bone stock (important for reconstruction, future revisions)
• Especially useful pelvic tumors (complex 3D anatomy)

Intraoperative Radiation Therapy (IORT)

Single-Dose Radiation to Tumor Bed: After tumor resection, radiation oncologist delivers 10-15 Gy directly to high-risk margins (e.g., sacral tumors where wide margin impossible without nerve sacrifice).

Benefits: Reduces local recurrence from 30-40% to 10-15% in marginally resected tumors. Spares surrounding healthy tissue (vs external beam radiation field).

Preventing Complications

Avoid "Whoops" Surgery

Never Excise Suspected Malignant Lesion Without Staging: Unplanned excision ("whoops" surgery) performed without oncologic principles spreads tumor cells throughout surgical field. Complicates definitive resection—may convert limb-salvage case to amputation. Local recurrence 2-3x higher.

Proper Pathway: X-ray → referral to bone tumor center → staging (MRI, chest CT) → biopsy → multidisciplinary board → neoadjuvant chemo (if applicable) → definitive resection by oncologic surgeon.

Pathological Fracture Prevention

Impending Fracture Criteria: >50% cortical destruction, >2.5 cm lytic lesion, persistent pain despite treatment.

Prophylactic Fixation: Nail or plate + cement BEFORE fracture occurs. Post-fracture surgery more difficult (contaminated hematoma), higher complication rate, longer recovery.

Infection in Endoprostheses

Risk: 5-10% prosthetic joint infection post-tumor resection (higher than primary joint replacement due to soft tissue compromise, chemotherapy-induced immunosuppression, longer operative time).

Prevention: Antibiotic-loaded cement, meticulous soft tissue reconstruction (muscle flaps cover implant), prophylactic antibiotics.

Treatment: Early infection (<4 weeks): Washout, implant retention. Late infection: 2-stage revision (remove prosthesis, antibiotic spacer, reimplant) or amputation if recurrent.

Why Ajuda for Bone Tumor Surgery?

Take the First Step

Bone tumors require urgent expert evaluation—weeks matter for diagnosis and staging. If you have persistent bone pain, unexplained mass, pathological fracture, or abnormal X-ray, call 9010550550 immediately for expedited consultation.

Early diagnosis and treatment at a specialized bone tumor center dramatically improves outcomes. Our multidisciplinary team guides you through every step—biopsy, chemotherapy, surgery, reconstruction, rehabilitation, and surveillance.

Trust Ajuda's musculoskeletal oncology program for expert bone tumor care and limb preservation.