Assessment of the added value of intravenous gadolinium for knee osteosarcoma resection planning in pediatric and young adult patients.

BACKGROUND AND OBJECTIVES: To assess the impact of Gadolinium-enhanced magnetic resonance imaging (MRI) sequences on Preoperative imaging evaluation and surgical planning parameters for osteosarcoma (OS) of the knee in pediatric and young adult patients.

METHODS: Thirty MRI scans of patients with OS about the knee were reviewed by five orthopedic oncologists. Key preoperative parameters (neurovascular bundle involvement, intra-articular tumor extension, extent of intramedullary extension) and surgical plans were evaluated based on non-contrast versus Gd contrast enhanced sequences. Assessment agreement, inter-rater agreement, and intrarater agreement between pre and postcontrast images were evaluated via Kappa statistics.

RESULTS: Moderate agreement was seen between non and contrast-enhanced assessment of neurovascular involvement and intra-articular tumor extension. Intrarater reproducibility was substantial for neurovascular bundle involvement (precontrast Kappa: 0.63, postcontrast Kappa: 0.69). Intrarater reproducibility was also substantial for precontrast (Kappa: 0.70) and moderate for postcontrast (Kappa: 0.50) assessment of intra-articular tumor extension. Planned resection length and choice of surgical approach were similar between sequences. The addition of Gd-enhanced sequences improved the inter-rater agreement across collected parameters.

CONCLUSIONS: While some findings suggest that contrast enhanced sequences may not significantly alter the assessment of key preoperative planning parameters by orthopedic oncologists, they may help reduce variability among providers with differing experience levels.