Martin Voss1, Kea Franz2, Joachim P Steinbach3, Emmanouil Fokas4, Marie-Thérèse Forster2, Katharina Filipski5, Elke Hattingen6, Marlies Wagner6, Stella Breuer6. 1. Dr. Senckenberg Institute of Neurooncology, University Hospital Frankfurt, Goethe University, Schleusenweg 2-16, 60528, Frankfurt am Main, Germany. martin.voss@kgu.de. 2. Departement of Neurosurgery, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany. 3. Dr. Senckenberg Institute of Neurooncology, University Hospital Frankfurt, Goethe University, Schleusenweg 2-16, 60528, Frankfurt am Main, Germany. 4. Department of Radiotherapy and Oncology, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany. 5. Institut of Neurology (Edinger-Institute), University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany. 6. Departement of Neuroradiology, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany.
Abstract
INTRODUCTION: Magnet resonance imaging (MRI) of gliomas is assessed by Response Assessment in Neuro-Oncology Criteria (RANO), which define new contrast-enhancing lesions as a sign for tumor recurrence. Pseudoprogression after radiotherapy may mimic tumor progression in MRI but is usually limited to the first months after irradiation. We noted a late onset pattern of new contrast-enhancing spots (NCES) appearing years after radiotherapy. METHODS: We prospectively collected 23 glioma patients with 26 NCES (three patients had two separate NCES events) between 2014 and 2016 in our weekly tumor board without further selection by diagnosis, molecular markers or pretreatment. RESULTS: Retrospective analysis revealed a homogeneous collective of young patients (median age of 49 years at NCES) with mainly IDH-mutated glioma (61%). Initial histology showed 26% glioblastoma, 52% grade III and 22% grade II glioma. NCES occurred at late follow-up with a median of 52 months after tumor diagnosis and 30 months after the last radiotherapy. The majority of NCES regressed spontaneously within a median of 10 months (n = 11) or remained stable without further therapy with a median follow-up of 26 months (n = 7). Only 4 NCES developed MRI morphologically into tumor recurrence. Two NCES were resected without any histopathological proof of tumor recurrence, and in 2 other cases NCES were defined as ischemic stroke or radionecrosis. CONCLUSION: We hypothesize that the late onset phenomenon of NCES predominantly represents a form of radiation-induced vasculopathy that is different from early pseudoprogression and should be considered especially in younger patients with IDH-mutated glioma before initiation of new therapy.
INTRODUCTION: Magnet resonance imaging (MRI) of gliomas is assessed by Response Assessment in Neuro-Oncology Criteria (RANO), which define new contrast-enhancing lesions as a sign for tumor recurrence. Pseudoprogression after radiotherapy may mimic tumor progression in MRI but is usually limited to the first months after irradiation. We noted a late onset pattern of new contrast-enhancing spots (NCES) appearing years after radiotherapy. METHODS: We prospectively collected 23 gliomapatients with 26 NCES (three patients had two separate NCES events) between 2014 and 2016 in our weekly tumor board without further selection by diagnosis, molecular markers or pretreatment. RESULTS: Retrospective analysis revealed a homogeneous collective of young patients (median age of 49 years at NCES) with mainly IDH-mutated glioma (61%). Initial histology showed 26% glioblastoma, 52% grade III and 22% grade II glioma. NCES occurred at late follow-up with a median of 52 months after tumor diagnosis and 30 months after the last radiotherapy. The majority of NCES regressed spontaneously within a median of 10 months (n = 11) or remained stable without further therapy with a median follow-up of 26 months (n = 7). Only 4 NCES developed MRI morphologically into tumor recurrence. Two NCES were resected without any histopathological proof of tumor recurrence, and in 2 other cases NCES were defined as ischemic stroke or radionecrosis. CONCLUSION: We hypothesize that the late onset phenomenon of NCES predominantly represents a form of radiation-induced vasculopathy that is different from early pseudoprogression and should be considered especially in younger patients with IDH-mutated glioma before initiation of new therapy.