Second course of stereotactic radiosurgery for locally recurrent brain metastases: Safety and efficacy

Abstract

In the present study, we have evaluated the efficacy and toxicity of repeated brain metastases (BM) stereotactic radiosurgery (SRS2) following local failure of a prior radiosurgical procedure (SRS1). Between December 1996 and August 2015, 30 patients with 36 BM underwent SRS2 with a median dose of 18Gy. All BM were located outside critical structures. Following SRS2, local control at 6 months and one year were respectively 82.9% (IC 95%: 67.6–91.9) and 67.8% (IC 95%: 51–81). On multivariate analysis, planning target volume (PTV) < 3cc (HR: 0.19 (0.1–0.52)) and whole brain radiotherapy (WBRT) prior to SRS2 (HR: 0.25 (0.1–0.64)) were significantly associated with a better local control. One- and two-year overall survival rates after SRS2 were respectively 65.5% (IC 95%: 47.3–80%) and 27.6% (IC 95%: 14.7–45.7). Median overall survival following SRS2 was 14.2 months (range 1–106). Nineteen (63%) patients died from progressive systemic disease. Three (10%) patients died from out-field progressive brain disease and 8 (27%) in-field. Concerning toxicities, edema, radionecrosis, and hemorrhages were identified in 5 (12.8%), 4 (10.2%), and 5 (12.8%) patients respectively. No toxicity resulted in a neurological deficit. On univariate analysis, toxicities were significantly associated with PTV > 7cc (p = 0.02) and all patients had a WBRT before SRS2. A second course of SRS for locally recurrent brain metastases showed encouraging rates of local control. This treatment led to acceptable toxicities, especially for brain metastases smaller than 7cc, in our selected cohort of patients with BM located outside critical structures. Further studies are needed.

Coregistration of Magnetic Resonance and [18F] Fludeoxyglucose–Positron Emission Tomography Imaging for Stereotactic Radiation Therapy Planning: Case Report in a Previously Irradiated Brain Metastasis With Recurrent Tumor and Radiation Necrosis

“…13 With reported 12month progression rates of 27.2% for unoperated 6 and 40% for resected BMs 5 after SRS, repeat irradiation is anticipated to be an increasingly used salvage therapy in this setting. 14,15 Combined with a reported occurrence of RN after initial SRS of 16% at 12 months with a plateaus at nearly 40% by 40 months, 7 these observations indicate that delineating recurrent tumor from RN in previously treated BM patients will become a more common clinical scenario. This distinction is of particular importance for clinical decision-making given that recurrent tumor can be effectively treated by reirradiation as noted earlier, or in the case of radiation necrosis, by other modalities such as laser interstitial thermal therapy.…”

Second Re-irradiation of Brain Metastases: A Review of Studies Involving Stereotactic Radiosurgery

“…We identified and reviewed six retrospective clinical studies of sequential WBRT and two courses of SRT [14-19]. Balermpas et al reported on 31 patients with 32 recurrent brain metastases (31% each with breast and non-small cell lung cancer [NSCLC]) [14].…”

“…Moreau et al [19] have published the largest dataset of interest ( n = 24), extracted from their analysis of 30 patients with 36 lesions (50% lung cancer, not stratified by histology). None of the patients had a neurological deficit at the time of second SRS.…”

“…Summarized, the patient numbers ranged from five to 24. For the first scenario (two series of SRT and one WBRT), six studies were eligible [14-19]. The typical sequence of radiotherapy (RT) was WBRT first, followed by SRT (overall 52 patients), while 13 patients finished their RT sequence with WBRT.…”

Outcomes of Metastatic Brain Lesions Treated with Radioactive Cs-131 Seeds after Surgery: Experience from One Institution

“…Today, focused methods such as SRS are more attractive in patients with oligometastatic brain metastases while WBRT is reserved for patients with higher burdens of intracranial disease [ 7 ]. SRS significantly limits the exposure of healthy brain tissue while delivering high doses of therapeutic radiation within a short period of time [ 8 ]. However, WBRT and SRS are both hampered by known complications in treating brain lesions.…”