assertion retraction graph subject predicate object datatype annotation 1 0 graph DOID:8243 IAO:0000115 A central nervous system melanocytic neoplasm that is characterized as an extra-axial well-encapsulated malignant tumour with diffuse meningeal growth and dark coloration (due to high melanin contents). xsd:string "{""oio:hasDbXref"":[{""datatype"":""xsd:string"",""meta"":""owl:Axiom"",""object"":""url:https://neurosurgery.directory/2020/10/04/diffuse-leptomeningeal-melanocytosis/""}]}"