Medical Care

Probably the most important factor in providing good care is the clinician's confidence of diagnosis. Exposing a patient with radiation necrosis to unwarranted antineoplastic treatment is not desirable.

A conservative option in treating a patient with radiation necrosis is observation. This may be appropriate for a patient found to have an asymptomatic necrotic mass on follow-up MRI. If the patient is asymptomatic and definitive diagnosis of radiation necrosis or recurrent glioma does not make a difference in clinical management, the patient should be monitored clinically and with serial MRI scans.

For patients with signs and symptoms of mass effect, increased intracranial pressure, or neurologic disability, consider other treatment options. Consider surgical evaluation, steroids, anticoagulation, or hyperbaric oxygen therapy separately or in combination.^{[37, 38, 39]}

A study of 14 patients with radiographic or biopsy proof of central nervous system radiation necrosis and progressive neurologic symptoms or signs responded to bevacizumab with decreases in T(2)-weighted fluid-attenuated inversion recovery and T(1)-weighted gadolinium-enhanced volumes and a decrease in endothelial transfer constant. This trial provided class I evidence of the efficacy of bevacizumab as a treatment for CNS radiation necrosis.^[40]

In another study of the efficacy of bevacizumab, researchers reviewed 14 lesions in 11 patients treated with bevacizumab for brain RN secondary to SRS for their brain metastases. The mean percentage decrease in RN volume seen on T1 post-Gadolinium and fluid-attenuated inversion recovery (FLAIR) MRI at first follow-up, at a mean of 26 days (range, 15-43 days), was 64.4% and 64.3%, respectively.^[41]

Hyperbaric oxygen promotes perfusion and angiogenesis.

Oxygen is delivered at 2-3 atm for 20-30 sessions. Each session lasts approximately 90-120 minutes.
Hyperbaric oxygen therapy is expensive, time-consuming, and not readily available at most medical centers.
Efficacy is not well documented.
Small case studies exist, but many of these patients also were receiving concomitant steroid therapy. These clinical series showed resolution of a lesion on MRI.^[37]
Hyperbaric oxygen can be provided in conjunction with anticoagulation.

Surgical Care

In addition to providing potential histologic diagnosis, surgery has other therapeutic benefits. Surgical debulking of the lesion can relieve increased intracranial pressure and improve disability. Patients with obstructive hydrocephalus may require a shunting procedure. Surgery, however, is associated with a high risk of complications or neurologic deficit and should be reserved for symptomatic patients in whom medical therapy fails.

Laser interstitial thermal therapy

Laser interstitial thermal therapy (LITT) can be used in cases where medical management has failed, and surgical treatment is either contraindicated due to high surgical risks or the lesion is in a surgically inaccessible location. In these cases, LITT can help control the perilesional edema and potentially reduce the dose of steroids required. LITT can help obtain a simultaneous biopsy, particularly in asymptomatic patients with serial imaging showing a progression. A few anecdotal pieces of evidence suggest that the LITT can completely resolve the radiation necrosis, improve overall survival, and have a better long-term reduction of lesional volume.^{[42, 43, 44]}

Medication

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Media Gallery

MRI of a patient with symptoms of gait unsteadiness 1 year after being diagnosed with a posterior fossa primitive neuroectodermal tumor (PNET). Treatment during the 1-year interval prior to this MRI consisted of surgical resection, craniospinal radiation of 2340 cGy, boost dose given to the posterior fossa for a total of 5500 cGy, chemotherapy (vincristine, cis-platinum, and cyclohexylchloroethylnitrosurea [CCNU]), and dexamethasone therapy.
Positron emission tomography with [18F]-labeled fluorodeoxyglucose (PET-FDG) performed following the MRI of a patient with symptoms of gait unsteadiness 1 year after being diagnosed with a posterior fossa primitive neuroectodermal tumor (PNET). Treatment during the 1-year interval prior to these studies consisted of surgical resection, craniospinal radiation of 2340 cGy, boost dose given to the posterior fossa for a total of 5500 cGy, chemotherapy (vincristine, cis-platinum, and cyclohexylchloroethylnitrosurea [CCNU]), and dexamethasone therapy. PET-FDG demonstrates hypometabolism consistent with probable radiation necrosis. Four years later, the patient is stable and without evidence of tumor progression.
T1-weighted contrast imaging shows left frontoparietal enhancing mass lesion with significant perilesional edema and midline shift. Peripheral wavy frond-like enhancement is typical of radiation necrosis.
T1-weighted contrast imaging after the corticosteroid administration showing a significant reduction in enhancement, swelling, and mass effect with reversal of midline shift.

of 4

Author

Gaurav Gupta, MD, FAANS, FACS Associate Professor of Neurosurgery, System Co-Director, Cerebrovascular and Endovascular Neurosurgery, Fellowship Director, Endovascular Neurosurgery Fellowship (Site), Department of Surgery, Division of Neurosurgery, Rutgers RWJ Barnabas Healthcare, Rutgers Robert Wood Johnson Medical School

Gaurav Gupta, MD, FAANS, FACS is a member of the following medical societies: American Academy of Neurology, American Association for the Advancement of Science, American Association of Neurological Surgeons, American College of Surgeons, American Heart Association, American Medical Association, Congress of Neurological Surgeons, Facial Pain Association, Society for Neuroscience, Society of NeuroInterventional Surgery

Disclosure: Nothing to disclose.

Coauthor(s)

Fareed R Jumah, MBBS Postdoctoral Research Fellow, Department of Neurosurgery, RWJ University Hospital, Rutgers Robert Wood Johnson Medical School

Disclosure: Nothing to disclose.

Bharath Raju, MBBS, MCh Postdoctoral Research Fellow, Department of Neurosurgery, RWJ University Hospital, Rutgers Robert Wood Johnson Medical School

Bharath Raju, MBBS, MCh is a member of the following medical societies: AOSpine, Bangalore Neurological Society, European Association of Neurosurgical Societies, Neurological Society of India, Neurotrauma Society of India

Disclosure: Nothing to disclose.

Sudipta Roychowdhury, MD Clinical Associate Professor of Radiology, Department of Radiology, Rutgers Robert Wood Johnson Medical School; Attending Radiologist/Neuroradiologist, University Radiology Group, PC

Sudipta Roychowdhury, MD is a member of the following medical societies: American College of Radiology, American Medical Association, American Society of Neuroradiology, Medical Society of New Jersey, Radiological Society of New Jersey, Radiological Society of North America, Society of NeuroInterventional Surgery

Disclosure: Nothing to disclose.

Anil Nanda, MD, MPH, FACS Professor and Chairman, Department of Neurosurgery, Rutgers University Robert Wood Johnson Medical School and Rutgers New Jersey Medical School; Peter W Carmel, MD, Endowed Chair of Neurological Surgery, Senior Vice President of Neurosurgical Services, RWJBarnabas Health

Anil Nanda, MD, MPH, FACS is a member of the following medical societies: American Academy of Neurological Surgery, American Association of Neurological Surgeons, American Medical Association, Brain Attack Coalition, Congress of Neurological Surgeons, John C McDonald Surgical Society, Louisiana Neurosurgical Society, Louisiana State Medical Society, North American Skull Base Society, Shreveport Medical Society, Society of Neurological Surgeons, Society of University Neurosurgeons, Southern Neurosurgical Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Jorge C Kattah, MD Head, Associate Program Director, Professor, Department of Neurology, University of Illinois College of Medicine at Peoria

Jorge C Kattah, MD is a member of the following medical societies: American Academy of Neurology, American Neurological Association, New York Academy of Sciences

Disclosure: Nothing to disclose.

Chief Editor

Stephen L Nelson, Jr, MD, PhD, FAACPDM, FAAN, FAAP, FANA Professor of Pediatrics, Neurology, Neurosurgery, and Psychiatry, Medical Director, Tulane Center for Autism and Related Disorders, Tulane University School of Medicine; Pediatric Neurologist and Epileptologist, Ochsner Hospital for Children; Professor of Neurology, Louisiana State University School of Medicine

Stephen L Nelson, Jr, MD, PhD, FAACPDM, FAAN, FAAP, FANA is a member of the following medical societies: American Academy for Cerebral Palsy and Developmental Medicine, American Academy of Neurology, American Academy of Pediatrics, American Epilepsy Society, American Medical Association, American Neurological Association, The Society of Federal Health Professionals (AMSUS), Child Neurology Society, Southern Pediatric Neurology Society

Disclosure: Nothing to disclose.

Additional Contributors

Michael J Schneck, MD, MBA Vice Chair and Professor, Departments of Neurology and Neurosurgery, Loyola University, Chicago Stritch School of Medicine; Associate Director, Stroke Program, Director, Neurology Intensive Care Program, Medical Director, Neurosciences ICU, Loyola University Medical Center

Michael J Schneck, MD, MBA is a member of the following medical societies: American Academy of Neurology, American Society of Neuroimaging, Neurocritical Care Society, Stroke Council of the American Heart Association

Disclosure: Nothing to disclose.

Frederick M Vincent, Sr, MD Clinical Professor, Department of Neurology and Ophthalmology, Michigan State University Colleges of Human and Osteopathic Medicine

Frederick M Vincent, Sr, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American College of Forensic Examiners Institute, American College of Legal Medicine, American College of Physicians

Disclosure: Nothing to disclose.

Anna Janss, MD, PhD Associate Professor of Pediatric Neuro-oncology, Emory University School of Medicine; Consulting Neuro-oncologist, Children's Healthcare of Atlanta

Anna Janss, MD, PhD is a member of the following medical societies: American Academy of Neurology, American Association for Cancer Research, American Medical Association, International Association for the Study of Pain, Pennsylvania Medical Society, Society for Neuroscience, Children's Oncology Group, Society for Neuro-Oncology

Disclosure: Nothing to disclose.

Acknowledgements

The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous author Robert Wilson, MD to the development and writing of this article.