M. W. Lu1,2, L. Van Houwelingen1, M. D. Neel1, A. M. Davidoff1, M. J. Krasin1, B. N. Rao1, I. Fernandez-Pineda1 1St. Jude Children’s Research Hospital,Surgery,Memphis, TN, USA 2University Of Tennessee Health Science Center,College Of Medicine,Memphis, TN, USA
Introduction:
Management of long bone metastasis from pediatric solid tumors and skeletal-related events (SREs) – including severe bone pain, immobility, and pathological/impending fracture – have not been widely described in children with cancer. We aimed to investigate the clinical presentation, SREs, management, and outcomes of pediatric solid tumor patients with long bone metastasis treated at our institution.
Methods:
Medical records of pediatric solid tumor patients with long bone metastasis treated at our institution between 2005 and 2015 were retrospectively reviewed. Variables analyzed included demographics, primary diagnosis, patterns of bony metastatic disease, management, and outcomes.
Results:
Ninety-nine patients (57 males, 42 females), median age at primary solid tumor diagnosis of 42 months (range, 1.5 – 247 months), were identified. Primary diagnoses included neuroblastoma (82), rhabdomyosarcoma (7), retinoblastoma (2), and other solid tumors (8). Seventy-five (76%) patients had both upper and lower extremity involvement; 22 (22%) had lesions limited to the lower extremities and 2 (2%) to the upper extremities. Eight (8%) patients had metastasis to a single long bone; 91 (92%) had metastasis to multiple long bones. Eighteen (18%) patients were diagnosed with long bone metastasis non-synchronous with their primary diagnosis with a median length of time to long bone metastasis diagnosis of 30.5 months (range, 3 – 60 months). Seventy-five (76%) patients presented with or experienced at least one SRE (67 patients had severe bone pain, 42 had immobility, and 14 had pathological fracture), of which 42 had more than one discrete SRE. Among patients with an SRE – 43 (57%) patients required only observation for their long bone metastasis; 27 (36%) patients required radiation, of which 21 were indicated for palliation; 12 (16%) patients required cast immobilization; and 4 (5%) patients required surgery: one had bony metastatic resection and 3 had prophylactic fixation for impending fracture. One patient had closed reduction of a pathological fracture. All 24 patients that did not experience an SRE required only observation.
Conclusion:
The most common pattern of long bone metastasis from pediatric solid tumors involves both upper and lower extremities with multiple bones affected. Neuroblastoma is the most common primary diagnosis. Most pediatric solid tumor patients with long bone metastasis are managed well with observation alone. Cast immobilization and palliative radiation are considered for patients who fail to improve with conservative management. Impending high-risk fracture is managed with prophylactic fixation; otherwise, surgery is rarely indicated. Although SREs are commonly seen among these patients, most are managed conservatively.