Long-term survival (>13 years) in a child with recurrent diffuse pontine gliosarcoma: a case report

Pediatric gliosarcoma (GS) is a rare variant of glioblastoma multiforme. The authors describe the case of an unusual pontine location of GS in a 9-year-old boy who was initially diagnosed with low-grade astrocytoma (LGA) that was successfully controlled for 4 years. Subsequently, his brain tumor transformed into a GS. Prior treatment of his LGA included subtotal tumor resection 3 times, standard radiation therapy, and Gamma Knife procedure twice. His LGA was also treated with a standard chemotherapy regimen of carboplatin and vincristine, and his GS with subtotal resection, high-dose cyclophosphamide, and thiotepa with stem cell rescue and temozolomide. Unfortunately, he developed disseminated disease with multiple lesions and leptomeningeal involvement including a tumor occupying 80% of the pons. Upon presentation at our clinic, he had rapidly progressing disease. He received treatment with antineoplastons (ANP) A10 and AS2-1 for 6 years and 10 months under special exception to our phase II protocol BT-22. During his treatment with ANP his tumor stabilized, then decreased, and, ultimately, did not show any metabolic activity. The patient's response was evaluated by magnetic resonance imaging and positron emission tomography scans. His pathology diagnosis was confirmed by external neuropathologists, and his response to the treatment was determined by central radiology review. He experienced the following treatment-related, reversible toxicities with ANP: fatigue, xerostomia and urinary frequency (grade 1), diarrhea, incontinence and urine color change (grade 2), and grade 4 hypernatremia. His condition continued to improve after treatment with ANP and, currently, he complains only of residual neurological deficit from his previous surgery. He achieved a complete response, and his overall and progression-free survival is in excess of 13 years. This report indicates that it is possible to obtain long-term survival of a child with a highly aggressive recurrent GS with diffuse pontine involvement with a currently available investigational treatment.