Central Nervous System Metastases from Pediatric Solid Tumors: A Single-Institution Study

Central nervous system (CNS) metastases from pediatric solid tumors are rare but represent a devastating complication. This study aims to provide insight into this rare clinical presentation with a retrospective analysis of pediatric patients with solid tumors and CNS metastases treated at our institution over the past 21 years. Out of 386 pediatric patients with solid tumors, 19 (4.9%) developed CNS metastases, and 17 patients with consent for research were included in further analyses. The most common tumor types were sarcomas, followed by neuroblastomas. CNS metastases were rarely diagnosed at initial presentation (17.6%) and more common at time of disease progression/recurrence, often with multifocal localization (68.8%). In patients with bone sarcomas, the most common pattern of CNS involvement was contiguous spread from bone metastases (71.4%), whereas neuroblastoma patients showed a higher proportion of distant intraparenchymal metastases. Survival after diagnosis of CNS metastases was poor, with a median of 9 months (range 0-85 months). Patients with sarcomas appeared to benefit from therapies directed to CNS metastases, including radiotherapy and repeated surgery, with a 2-year overall survival of 66.7% (95% confidence interval: 5.4%-94.5%) for soft tissue sarcomas and a 2-year overall survival of 57.1% (95% confidence interval: 17.2%-83.7%) for bone sarcomas. For rare tumor types, such as BCL6 corepressor internal tandem duplication sarcomas, CNS metastases may be treatable and underrecognized, and incorporating routine CNS imaging in follow-up could be beneficial. Though data are scarce, our findings suggest that whenever feasible, tumor debulking or stereotactic biopsy should be considered for local treatment and/or molecular profiling in pediatric patients with CNS metastases.