INTRODUCTIONLimb salvage in children with primary malignant bone tumours around the knee is challenging, with considerations such as shortening, bone and joint remodeling and high functional demands of active children. The ultimate aim for reconstruction is restoring a stable, painless and mobile joint. With improved survival rates from chemotherapy, reconstructive techniques should ideally last the child's lifespan. We adopted a biological approach by preserving the patients' native joint, with bony defects bridged by fibula grafts supplemented by autoclaved bone grafts infused with bone marrow. We conducted this retrospective review to determine if we were able to meet our objectives of reconstruction.

MATERIALS AND METHODSA retrospective review of children with osteogenic sarcoma involving the distal femur or proximal tibia treated at our institution was done. Patients aged 13 years and below at the time of surgery who had undergone a limb salvage procedure that preserved the knee joint were included.

RESULTSNine patients were identified, 3 males and 6 females. The average age was 10.0 years (range, 7 to 13 years) at the time of surgery. Seven had tumours involving the distal femur while 2 had tumours involving the proximal tibia. There were no cases of local recurrence. Four of the 9 patients died from metastatic disease, the 5 surviving patients have no evidence of disease, and the average follow-up for survivors was 13.2 years. The average active range of motion for the knee joint was 96° (range, 50° to 130°). The average Musculoskeletal Tumour Society (MSTS) score was 26.3 (range, 23 to 30).

CONCLUSIONWe have observed this technique of limb salvage offers satisfactory limb function with long-term follow-up.

Adolescent ; Bone Neoplasms ; surgery ; Child ; Female ; Femoral Neoplasms ; surgery ; Humans ; Knee Joint ; surgery ; Limb Salvage ; methods ; Male ; Osteosarcoma ; surgery ; Recovery of Function ; Retrospective Studies ; Tibia ; Time Factors ; Treatment Outcome

INTRODUCTIONMore than 80% of children with osteogenic sarcoma (OS) relapse and 35% to 40% of them die within the first 2 years after diagnosis due to relapse. We investigated the incidence, treatment modalities used and the outcome of patients with OS treated in Singapore.

MATERIALS AND METHODSPatients with OS treated in Department of Paediatrics KK Women's and Children's Hospital (KKH) and National University Hospital (NUH) between January 1994 and June 2011 were reviewed. Chemotherapy was as per the European Osteosarcoma Intergroup (EOI) and as per the Memorial Sloan-Kettering Cancer Centre's (MSKCC) T12 protocols. Overall and event-free (EFS) 5-year survivals were calculated using Kaplan-Meier analysis and Cox proportional hazards regression analysis.

RESULTSOf 66 patients with OS, 19 (29%) of them presented with metastatic OS. The median age of diagnosis was 12.1 years with 5-year overall survival of 61.7% (95% CI, 48.1 to 75.3). The 5-year overall survival for those with non-metastatic and metastatic OS was 73.1% (95% CI, 58.1 to 88.1) and 34.7% (95% CI, 8.7 to 60.7, P=0.007) respectively. The 5-year overall survival for those treated as per the MSKCC T12 and EOI was 72.4% (95% CI, 52.6 to 92.2) and 54.3% (95% CI, 36.3 to 72.3, P=0.087) respectively. After controlling for confounding factors, patients with non-metastatic OS had higher 5-year EFS (HR, 0.228, 95% CI, 0.096 to 0.541, P=0.001) and overall survival (HR, 0.294, 95% CI, 0.121 to 0.713, P=0.007) compared to those with metastatic OS. Non-metastatic OS patients treated as per EOI regimen had lower 5-year EFS (HR, 2.397, 95% CI, 1.012 to 6.678, P=0.047) compared to those treated per MSKCC T12 regimen.

CONCLUSIONMultidrug combination chemotherapy including high-dose methotrexate (HD-MTX) and a multidisciplinary team approach introduced in 2003 in Singapore is well tolerated and can be safely delivered. The survival benefit between the 2 regimens still needs to be explored.

Adolescent ; Bone Neoplasms ; drug therapy ; mortality ; Child ; Child, Preschool ; Female ; Humans ; Male ; Osteosarcoma ; drug therapy ; mortality ; Survival Rate ; Young Adult