Drop metastases are metastases that spread caudally due to gravity. These are intradural extramedullary masses arising from intracranial masses[^1].
Epidemiology
Drop metastases occur in 5-30% of all children with a brain tumor, with medulloblastoma being the most common cause and accounting for about half of all drop metastases in children[^3]. Drop metastases occur in about 1% of all patients with glioblastoma[^1].
Tumor entities
Drop metastases can be caused by various intracranial tumors[^2]:
Location
Drop metastases occur most commonly in the lower thoracic spine as well as the lumbar spine[^1].
Symptoms
Drop metastases typically cause back pain and may be associated with corresponding neurologic deficits.