Delayed evolution of an asymptomatic brainstem lesion into H3 K27-altered diffuse midline glioma in an adolescent

Key Points

• To describe a rare case of a brainstem lesion evolving into a H3 K27-altered diffuse midline glioma after a long period of stability.
• Case report detailing the history of the brainstem lesion over seven years.
• Imaging studies conducted to monitor the lesion's stability and changes before diagnosis.
• The brainstem lesion remained radiologically stable for seven years before rapid progression.
• Diagnosis of H3 K27-altered diffuse midline glioma was confirmed upon accelerated progression.