MEDB-10. Comparing pediatric medulloblastoma with and without spinal metastasis

AIM: To compare pediatric medulloblastoma with and without spinal metastasis METHODOLOGY: Pediatric medulloblastoma cases from 1999 to 2021 were retrospectively reviewed in this Institutional Review Board approved study. Imaging reports, presence of spinal drop metastases at diagnosis, degree of tumor excision, treatment given and survival status were captured. RESULTS: Brain and spine imaging at diagnosis was available in 54 medulloblastoma patients with no drop metastasis and in 7 with drop metastasis. Largest tumor dimension at presentation is 4.54 ± 0.94 cm with those with drop metastasis, similar to the 4.43 ± 0.94 cm in those without drop metastasis (p = 0.79). For the 54 medulloblastomas with no drop metastasis, 44 (81%) were completely excised, 9 (17%) partially excised and there was no follow up for 1. For the 7 medulloblastomas with drop metastasis, 3 (43%) of the primary tumours were completely excised, 3 (43%) partially excised and there was no follow up for 1. Post operative chemo/radiotherapy was given to 48 of the 54 with no drop metastasis, not given for 1 with no information available for 5. Chemo/radiotherapy was given to 6 of the 7 with drop metastasis with no information available for 1. At 1 year follow up of the 54 with no spinal drop metastasis at diagnosis , 42 remain tumour free, 3 have tumour, 4 are deceased and 5 are lost to follow up. At 1 year follow up of the 7 with drop metastasis, 2 are free of tumour, 2 have tumour and 3 are lost to follow up. Higher percentage of medulloblastomas without drop metastasis are completely excised (p<0.01). No significant difference between postoperative chemotherapy/radiation rates between groups CONCLUSION: Most medulloblastomas do not have spinal drop metastasis at diagnosis and complete excision is more frequently in those without drop metastasis.