Spontaneous remission of a “diffuse glioma” – A case report

•Some brain tumors can spontaneously disappear, but inflammatory processes can mimic a brain tumor and should be taken into consideration as differential diagnosis.•In doubt, additional imaging such as magnetic resonance spectroscopy and CSF examination should be performed before starting therapy with dexamethasone to rule out inflammatory processes.•Up-to-date imaging is necessary due to changes in tumor size in a short time.