LGG-03. Pediatric spinal deformities concomitant with spinal cord pilocytic astrocytoma

INTRODUCTION: Childhood spinal cord tumours may lead to spinal deformity. Rapid scoliosis progression, a left thoracic curve and early onset scoliosis are associated with an increased risk of intraspinal anomalies, therefore magnetic resonance imaging (MRI) should be performed. CASE PRESENTATION: A 1-year-old girl presented with progressive early onset scoliosis. MRI of the spine showed diffuse intramedullary lesion at vertebral level T5 – T11 and abnormal curvature of the thoracic spine to the right – 39-degree Cobb angle, after a few moths – 71-degree. Blood and cerebrospinal fluid examination ruled out a neuroinfection and autoimmune diseases. Histology revealed BRAF V600E-mutant pilocytic astrocytoma (PA) (IDH non-mutant), DNA methylation profiling – PA, MGMT promoter methylation – not detected, SNP-A karyotyping – normal. Treatment with weekly vinblastin was started due to non-operable tumour and progressive scoliosis. Spinal deformity was managed using serial casting with only mild correction of curvature. In the second case report, a 14-year-old boy either presented with progressive scoliosis. Spine x-ray showed abnormal curvature of the thoracic spine to the left - 89-degree Cobb angle and after a few years - 120-degree. MRI of the spine detected intramedullary tumour masses located at vertebral level T3-T5. Surgical resection revealed BRAF V600E-mutant PA (IDH, ATRX, TERT non-mutant), DNA methylation profiling – PA, MGMT promoter status – not methylated, SNP-A karyotyping – non-specific trisomy of chromosome 5. The patient was followed-up by routine spine MRI. However, after 8 months new spinal cord masses appeared. It was decided to correct scoliosis only after the total tumour removal. CONCLUSIONS: Intramedullary spinal tumours are overall rare in the pediatric population. Of these, PA accounts for the majority, however treatment remains challenging. BRAF V600E mutation has relatively high frequency in PA. This mutation identification opens more treatment options such as targeted therapy with BRAF V600E and MEK inhibitors for progressive disease.