Long-Term Follow-Up of a Child with EWSR1-BEND2 Fused Spinal Astroblastoma.

Introduction: Spinal astroblastoma is a rare highly malignant tumor that mainly affects children. We review the few cases described in the literature and highlight the challenges of managing this neoplasm by illustrating a case recently treated at our institutions. To our knowledge, this is the first published case of EWSR1-BEND2 fused spinal astroblastoma with long-term follow-up.

Case presentation: An 8-year-old girl was transferred from her home country to Switzerland for treatment of a recurrent intramedullary tumor of the cervical spine extending from C2-C7. The tumor was primarily diagnosed as an ependymoma of the spinal cord. Prior to her transfer to our department, the patient had undergone subtotal resection of the lesion, radiation therapy, multiple chemotherapy regimens, and biopsy of the recurrent tumor. Clinically, the patient presented with tetraparesis and had recently experienced worsening upper extremity weakness with complete loss of hand function. We performed a near total resection of the recurrent tumor. Ultra-fast Nanopore seq® based DNA methylome profiling allowed confirmation of the molecular diagnosis of a high-grade neuroepithelial tumor (HGNET-MN1) consistent with astroblastoma in less than 2 h, with subsequent molecular workup revealing a EWSR1-BEND2 fusion. After surgery, the patient gradually regained function in her hands. She was sent to a specialized pediatric rehabilitation center, and while the tumor was being followed radiologically with no adjuvant treatment planned, the patient presented with a relapse of the tumor in only 3 months. Given the acute worsening of radiating pain and sudden respiratory failure, a cervical decompression was performed. MRI of the cervical spine showed infiltration of the lower aspects of the brainstem. The patient was offered palliative comfort care.

Conclusion: Spinal astroblastoma is a rare and highly aggressive tumor affecting children and young adults with a high recurrence rate and thus far not well-defined prognosis. The molecular signature of astroblastoma needs to be further characterized to establish a treatment-relevant classification and to allow a better prognostication. Currently, gross-total resection combined with radiotherapy remains the mainstay of treatment for spinal astroblastoma.