Interventions for the treatment of brain radionecrosis after radiotherapy or radiosurgery

Abstract

There is a lack of good certainty evidence to help quantify the risks and benefits of interventions for the treatment of brain radionecrosis after radiotherapy or radiosurgery. In an RCT of 14 patients, bevacizumab showed radiological response which was associated with minimal improvement in cognition or symptom severity. Although it was a randomised trial by design, the small sample size limits the quality of data. A trial of edaravone plus corticosteroids versus corticosteroids alone reported greater reduction in the surrounding oedema with combination treatment but no effect on the enhancing radionecrosis lesion. Due to the open-label design and wide confidence intervals in the results, the quality of this data was also low. There was no evidence to support any non-pharmacological interventions for the treatment of radionecrosis. Further prospective randomised studies of pharmacological and non-pharmacological interventions are needed to generate stronger evidence. Two ongoing RCTs, one evaluating bevacizumab and one evaluating hyperbaric oxygen therapy were identified.

Bevacizumab for radiation necrosis following radiotherapy of brain metastatic disease: a systematic review & meta-analysis

“…Targeted agents after SRS for the brain have also been continued and have prolonged survival outcomes for patients with BM [6,7,9,15,16]. Radiation therapy has long been associated with the development of radiation necrosis (RN) in patients with intracranial disease [17][18][19][20][21]. The rate of RN following radiotherapy or radiosurgery has been estimated at 10-15% [17][18][19][20][21].…”

“…Radiation therapy has long been associated with the development of radiation necrosis (RN) in patients with intracranial disease [17][18][19][20][21]. The rate of RN following radiotherapy or radiosurgery has been estimated at 10-15% [17][18][19][20][21]. RN is considered as a dose-limiting toxicity for SRS [20,21].…”

“…Corticosteroids have long been the mainstay of RN treatment. It inhibits the pro-inflammatory response that promotes radiation necrosis and provides symptomatic relief via edema reduction, but long-term use is associated with serious side effects [19]. Surgery has also been used for resectable progressive RN, which can relieve mass effects and it also provides an opportunity to study tissue samples for diagnosis.…”

“…Surgery has also been used for resectable progressive RN, which can relieve mass effects and it also provides an opportunity to study tissue samples for diagnosis. However, persistent edema may need close monitoring for weeks [19,24]. Another treatment strategy employed is hyperbaric oxygen therapy (HBOT) [25].…”

Hyperbaric Oxygen for Radiation Necrosis of the Brain

“…Patients who are asymptomatic can be observed, while those who are symptomatic are managed with corticosteroids, hyperbaric oxygen therapy (HBOT), bevacizumab, pentoxifylline, vitamin E, laser-induced thermal therapy and/or surgery. [6][7][8][9][10] A recent Cochrane systematic review showed paucity of data on the topic, and was only able to include three comparative studies that used bevacizumab, edaravone and vitamin E. 11 HBOT is a non-invasive treatment that may stabilise necrosis, promote tissue repair and expedite neurological recovery. 12,13 Small retrospective studies have demonstrated high rates of benefit with either rates of stability or improvement estimated at 70%-80% of treated patients.…”