ABSTRACT: Abstract BACKGROUND: Prognosis of patients with recurrent medulloblastoma and atypical teratoid rhabdoid tumor (ATRT) is dismal despite intensive therapy including high-dose chemotherapy with stem cell rescue. We report on 28 patients with recurrent medulloblastoma and ATRT treated with an alternative approach to conventional chemotherapy that targets neovascularisation by interfering with tumor angiogenesis at various levels. Patients and METHODS: From 11/2006 to 06/2016, 28 patients were diagnosed with recurrent embryonal tumors, 20 with a recurrent medulloblastoma (13 first, 7 multiple recurrences) and eight with recurrent ATRT (5 first, 3 multiple), three had germ line mutations. Treatment consisted of an antiangiogenic multidrug-regime including IV bevacizumab, oral thalidomide, celecoxib, fenofibrate, and etoposide alternating with cyclophosphamide, and augmented with intraventricular therapy (etoposide and liposomal cytarabine). Median age at start of antiangiogenic therapy was 10 (1–24) years for medulloblastoma and 1.5 (1–13) years for ATRT. Results: As of 11/2016, 12/20 patients with medulloblastoma are alive at a median of 25 (12–97) months after their last recurrence. 8/12 surviving patients are currently in CR for 97, 94, 93, 29, 27, 23, 19 and 18 months, five off therapy for 79, 62, 60, 22 and 18 months, three are in PR 23, 12 and 2 months after their last recurrence and one patient has stable disease 12 months after her last recurrence. 5-year-OS is 57.6?±?13.2%. One patient died of an accident in CR 23 months after initiation of antiangiogenic therapy and one patient with a very good PR died of a septicemia seven months after his last recurrence. Two patients had prior been treated with the same antiangiogenic approach and had recurred 67 and 40 months after their last recurrence while off therapy for 36 and 21 months and both patients are in remission again, one off therapy for 18 months. 3/8 patients with ATRT are alive. Follow-up since last recurrence is 72, 27 and 24 months and all patients are off therapy for 52, 14 and 13 months. One patient died of another cause without evidence of tumor at autopsy 54 months after recurrence and while off therapy for 46 months. One surviving patient with a germ line mutation and a fourth recurrence was prior treated with the same approach albeit without intrathecal therapy. He recurred 78 months after his last recurrence while off therapy for 36 months. He is again in CR and off therapy for 13 months. Therapy is primarily outpatient, was generally well tolerated, and toxicities were manageable. CONCLUSION: The proposed antiangiogenic regimen is currently being evaluated for medulloblastomas in an international phase II protocol (MEMMAT; ClinicalTrials.gov Identifier: NCT01356290). The same approach seems to be also efficacious in recurrent ATRTs and warrants further evaluation.
