Sandy Mong1, Ben M. Ellingson, Timothy F. Cloughesy2, Kim J. Hyun3, Albert Lai2, Phioanh Leia Nghiemphu2, Leili Mirsadraei4, William H. Yong4, Whitney B. Pope3
1Radiology , UCLA, Los Angeles, CA, United States; 2Neurology, UCLA; 3Radiology, UCLA; 4Pathology, UCLA
The aim of this study was to characterize the evolution and prognostic significance of persistent diffusion restriction abnormalities in patients with malignant glioma treated with bevacizumab. These patients demonstrated greater time to progression, time to survival from initiation of bevacizumab treatment and overall survival compared to matched controls. Advanced imaging correlated these diffusion signal abnormalities with hypoperfusion and decreased activity on PET scans. Histopathological examination of a resection specimen confirmed necrosis in one patient. Thus, the presence of diffusion restricted lesions in patients with malignant glioma appears to reflect treatment effect rather than hypercellular tumor in a majority of cases.