Clinical and molecular characterization of a multi-institutional cohort of pediatric spinal cord low-grade gliomas.

BACKGROUND

The mitogen-activated protein kinases/extracelluar signal-regulated kinases pathway is involved in cell growth and proliferation, and mutations in have made it an oncogene of interest in pediatric cancer. Previous studies found that mutations as well as fusions are common in intracranial low-grade gliomas (LGGs). Fewer studies have tested for the presence of these genetic changes in spinal LGGs. The aim of this study was to better understand the prevalence of BRAF and other genetic aberrations in spinal LGG.

METHODS

We retrospectively analyzed 46 spinal gliomas from patients aged 1-25 years from Children's Hospital Colorado (CHCO) and The Hospital for Sick Children (SickKids). CHCO utilized a 67-gene panel that assessed and additionally screened for other possible genetic abnormalities of interest. At SickKids, was assessed by droplet digital polymerase chain reaction and immunohistochemistry. BRAF fusions were detected by fluorescence in situ hybridization, reverse transcription polymerase chain reaction, or NanoString platform. Data were correlated with clinical information.

RESULTS

Of 31 samples with complete fusion analysis, 13 (42%) harbored . All 13 (100%) patients with confirmed survived the entirety of the study period (median [interquartile range] follow-up time: 47 months [27-85 months]) and 15 (83.3%) fusion-negative patients survived (follow-up time: 37.5 months [19.8-69.5 months]). Other mutations of interest were also identified in this patient cohort including , , , , , and deletion.

CONCLUSION

was seen in higher frequency than or other genetic aberrations in pediatric spinal LGGs and experienced lower death rates compared to negative patients, although this was not statistically significant.