Treatment of recurrent high-grade gliomas
Despite treatment, glioblastoma (GB) inevitably recurs, and there is often no clear standard of care to follow. This article reviews the treatment options for recurrent GB and anaplastic gliomas. The three FDA-approved treatments for recurrent GB are biodegradable carmustine-impregnated wafers; bevacizumab; and the NovoTTF-100A System, which delivers low-intensity, alternating electrical fields to the tumor bed. Treatment decisions must take into consideration prior therapies, the extent and location of recurrence, and the patient’s general medical condition, as well as the rapidity of tumor growth, extent of edema, mass effect, need for steroids, and symptoms. New treatment strategies are emerging based on the identification of prognostic and predictive markers and defining distinct molecular subtypes of GB.
ABOUT THE AUTHORS
Affiliations: Dr. Rosenfeld is Adjunct Professor of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA; Ms. Albright is a Certified Registerd Nurse Practitioner at the University of Pennsylvania School of Medicine; and Dr. Pruitt is Associate Professor of Neurology at the University of Pennsylvania School of Medicine.
Conflicts of interest: The authors have nothing to disclose.
FIGURE 1 Pseudoprogression after chemoradiation. MRI of a biopsy-proven grade III astrocytoma before treatment (left panel). Three weeks after completion of chemoradiation, there is an increase in the size of the cystic component and enhancement (middle panel), which could be interpreted as tumor progression. After 4 cycles of post-radiation temozolomide, the right panel shows a decrease in size and enhancement, supporting the earlier imaging changes as reflective of pseudoprogression. All images are T1 post gadolinium with a 1.5 Tesla magnet.
FIGURE 2 Imaging changes with bevacizumab. This 57-year-old woman presented with a second recurrence of glioblastoma 2 years after chemoradiation and 6 cycles of adjuvant temozolomide and 6 months after 8 cycles of low-dose temozolomide. The images show post-contrast T1-weighted sequences (A, C, E) and fluid-attenuated recovery (FLAIR) sequences (B, D, F). Baseline images (A, B) show a left frontal mass with enhancement, edema, and some mass effect. Eight months later, after 4 cycles of bevacizumab (dosed every 2 weeks with 3 doses per cycle), there is decreased periventricular enhancement and edema (C) and improved FLAIR signal (D) but enlargement of the enhancing left frontal mass, which would meet standard definitions of tumor progression. The patient was neurologically stable and remained on treatment. Nine months later, after 5 additional cycles, she remained neurologically stable (and was not receiving corticosteroids). At this time, the mass has continued to increase in size (note: there is also invasion of the frontal sinus; E), with increasing FLAIR abnormality, likely reflecting a progressive infiltrating nonenhancing tumor (F).
