Stereotactic reirradiation for local failure of brain metastases following previous radiosurgery: Systematic review and meta-analysis

Abstract

Introduction: Local failure (LF) following stereotactic radiosurgery (SRS) of brain metastases (BM) may be treated with a second course of SRS (SRS2), though this procedure may increase the risk of symptomatic radionecrosis (RN). Methods: A literature search was conducted according to PRISMA to identify studies reporting LF, overall survival (OS) and RN rates following SRS2. Meta-analysis was performed to identify predictors of RN. Results: Analysis included 11 studies (335 patients,389 metastases). Pooled 1-year LF was 24 %(CI95 % 19-30 %): heterogeneity was acceptable (I2 = 21.4 %). Median pooled OS was 14 months (Confidence Interval 95 %, CI95 % 8.8-22.0 months). Cumulative crude RN rate was 13 % (95 %CI 8 %-19 %), with acceptable heterogeneity (I2 = 40.3 %). Subgroup analysis showed higher RN incidence in studies with median patient age ≥59 years (13 % [95 %CI 8 %-19 %] vs 7 %[95 %CI 3 %-12 %], p = 0.004) and lower incidence following prior Whole Brain Radiotherapy (WBRT, 19 %[95 %CI 13 %-25 %] vs 7%[95 %CI 3 %-13 %], p = 0.004). Conclusions: SRS2 is an effective strategy for in-site recurrence of BM previously treated with SRS.

Tumor Control Probability After Radiosurgery of Brain Metastases With and Without Retreatment

“…There is a balance between tumor coverage and normal tissue toxicity, and the dose prescribed for 2 nd SRS is variable [4,6,10,11,24]. At our institution, the dose prescribed for the tumor was essentially the same during retreatment.…”

“…While SRS has been considered an optimal treatment strategy for limited recurrent BM lesions [2,4], there is no consensus treatment recommendations [2] and the prescribed treatment dose for the 2 nd SRS is variable in published studies [4,6,10,11,24]. In this study, we modeled the TCP for 46 recurrent and 349 non-retreatment BM lesions to predict the relation between local control and dose delivered to the tumor volume.…”

“…Whole-brain radiation therapy (WBRT) as a sole modality is limited in achieving durable local control, and patients are challenged by significant toxicities such as a decline in cognitive function. Radiosurgery for recurrent BMs is considered a potentially useful strategy [3,4]. In a recent systematic review on recurrent BMs, a second/repeat SRS treatment was an effective strategy for local recurrence of BMs after initial SRS, with similar results to surgical series in terms of local control and overall survival [5].…”

Local Consolidative Therapy for Oligometastatic Non-Small Cell Lung Cancer

“…Furthermore, a few predictive nomograms have also been developed in the context of oligometastatic NSCLC. One nomogram model found that KPS, primary tumor histology, primary tumor control, size of the largest metastasis, and the number of metastases (1 vs. >1) were significant prognostic factors for OS after SBRT [ 62 ]. A smaller, more recent study showed that the solitary site of metastasis, targetable mutations, intracranial disease, and metachronous oligometastases were all predictive of larger PFS benefits after LAT [ 63 ].…”

Contribution of spectroscopic magnetic resonance imaging to target volume delineation in Gamma Knife Radiosurgery: Myth or reality?

“…Recently, we described the development of the first software allowing the integration of metabolic cartography based on multivoxel spectroscopic MRI in the radiosurgical planning for Leksell Gamma Knife Radiosurgery. The few existing meta-analysis could not lead to gold standard volume delineation techniques despite objective advance in imaging assessment [8,9]. Prospective studies using multimodal imaging data will help to overcome this insufficiency for target delineation in radiosurgery.…”