PEDT-07 RECURRENT MEDULLOBLASTOMA 9 YEARS AFTER THE PRIMARY TUMOR

Medulloblastoma is one of the most common malignant brain tumors in children. Despite multi-disciplinary treatment for medulloblastoma, including surgery, chemotherapy, and radiation, which have resulted in significant improvement of the prognosis, about 30% of patients still experience recurrence. Most recurrences occur within the first 15 months from diagnosis and late relapse of the tumor is quite rare. We report a case of a 15-year-old female patient with recurrent medulloblastoma 9 years after the primary tumor. At the age of 6, this patient developed a posterior fossa tumor without metastasis and underwent near-total resection. The pathological diagnosis was medulloblastoma with focal desmoplasia. After the surgery, she received multi-agent chemotherapy and radiation therapy consisting of 18 Gy craniospinal irradiation and 51.2 Gy local irradiation. She was in complete remission for 9 years after the treatment. However, gait disturbance began to gradually appear, and magnetic resonance imaging (MRI) showed an intradural lesion in her thoracic spine. The lesion was biopsied, and the pathological findings confirmed the recurrence of medulloblastoma. Currently, we plan to administer local radiation therapy concomitantly with temozolomide to the patient. The case reminds us of the importance of long-term careful follow-up of patients with medulloblastoma. Further studies are warranted for the treatment of relapsed medulloblastomas due to the limited information available at present.