Multifocal medulloblastoma in an adult: a case report and review of the literature.

Background: Medulloblastoma (MB) is a highly aggressive tumor originating in the cerebellum, predominantly affecting children. Adult medulloblastoma is rare, leading to a lack of a standardized treatment protocol. Although multimodal strategies from pediatric MB have improved outcomes in adult patients, challenges persist, including early diagnosis difficulties, treatment toxicity, recurrence risks, targeted therapies, and controversies over chemotherapy timing and regimen.

Case description: We present a clinical case involving a 53-year-old male patient diagnosed with multifocal medulloblastoma, who presented with symptoms of dizziness. Cranial magnetic resonance imaging (MRI) revealed space-occupying lesions in the right cerebellar infratentorial region and the right temporal pole, which were initially suspected to be meningiomas. The patient subsequently underwent surgical resection of the subtentorial lesion, which was pathologically confirmed to be a medulloblastoma. Molecular classification through genetic testing classified it as the SHH subtype. Postoperatively, the patient received sequential radiotherapy and chemotherapy. After radiotherapy, the lesion in the temporal pole disappeared, and the patient recovered well. Disease-free survival of this patient was more than 2 years, during which the patient returned to the hospital for follow-up every three months. Currently, the patient is in good condition with no significant treatment sequelae or signs of recurrence.

Conclusion: Adult medulloblastoma is rare, and adult multifocal medulloblastoma is even rarer. The adult patient with multifocal medulloblastoma we report underwent surgery followed by sequential radiotherapy and chemotherapy, resulting in a favorable prognosis. This may suggest that postoperative radiotherapy combined with chemotherapy could be effective in controlling adult medulloblastoma.