Radiosurgery for brain metastases: is whole brain radiotherapy necessary?

Propensity score-matched analysis comparing hippocampus-avoidance whole-brain radiotherapy plus simultaneous integrated boost with hippocampus‑avoidance whole-brain radiotherapy alone for multiple brain metastases-a retrospective study in multiple institutions

BACKGROUND

The optimal treatment for multiple brain metastases has been recently controversially discussed.This study was aimed to explore the feasibility of Hippocampus-Avoidance Whole-Brain Radiotherapy plus a simultaneous integrated boost (HA-WBRT + SIB) in patients with multiple brain metastases and assess tumor control in comparison with Hippocampus-Avoidance Whole-Brain Radiotherapy (HA-WBRT) alone for brain metastases.

METHODS

In this study, 63 patients with multiple brain metastases (≥ 4 metastases) had undergone HA-WBRT + SIB between January 2016 and December 2020 in the observation group:HA-WBRT (30 Gy in 12 fractions, the maximum dose of the hippocampus ≤ 14 Gy) plus a simultaneous integrated boost (48 Gy in 12 fractions) for brain metastases.Overall Survival (OS), Median survival,intracranial control (IC = control within the entire brain), intracranial progression-free survival (iPFS) and adverse events were compared with the control group (a HA-WBRT retrospective cohort) by propensity score matching analysis.

RESULTS

After 1:1 propensity score matching,there were 56 patients in each group (the observation group, the control group). OS, median survival and iPFS were significantly longer in the observation group (18.4 vs. 10.9 months, P<0.001), (13.0 vs. 8.0 months, P<0.001), (13.9 vs.7.8 months, P<0.001). In comparison of 1-year-IC rates, the observation group also demonstrated higher than the control group (51.8% vs. 21.4%, P = 0.002), respectively. Seven hippocampal metastases were found in the control group (4/56,7.1%) and the observation group (3/56,5.4%) after HA-WBRT. The death rate of intracranial progression were 23.2% in the observation group and 37.5% in the control group.All adverse events were not significant difference between the two groups (P>0.05).

CONCLUSIONS

HA-WBRT + SIB resulted in better OS,median survival, IC, iPFS, an acceptable risk of radiation response, and a potential way of declining neurocognitive adverse events, which may be a better treatment for patients with multiple brain metastases.

Efficacy of Stereotactic Radiosurgery as Single or Combined Therapy for Brain Metastasis: A Systematic Review and Meta-Analysis

To determine the efficacy of stereotactic radiosurgery (SRS) in treating patients with brain metastases (BMs), a network meta-analysis (NMA) of randomized controlled trials (RCTs) and a direct comparison of cohort studies were performed. Relevant literature regarding the effectiveness of SRS alone and in combination with whole-brain radiotherapy (WBRT) and surgery was retrieved using systematic database searches up to April 2019. The patterns of overall survival (OS), one-year OS, progression-free survival (PFS), one-year local brain control (LBC), one-year distant brain control (DBC), neurological death (ND), and complication rate were analyzed. A total of 18 RCTs and 37 cohorts were included in the meta-analysis. Our data revealed that SRS carried a better OS than SRS+WBRT (p= 0.048) and WBRT (p= 0.041). Also, SRS+WBRT demonstrated a significantly improved PFS, LBC, and DBC compared to WBRT alone and SRS alone. Finally, SRS achieved the same LBC as high as surgery, but intracranial relapse occurred considerably more frequently in the absence of WBRT. However, there were not any significant differences in ND and toxicities between SRS and other groups. Therefore, SRS alone may be a better alternative since increased patient survival may outweigh the increased risk of brain tumor recurrence associated with it.

Outcomes of single brain metastasis treated with gamma knife stereotaxic radiosurgery(GKSR). Our experience on 103 cases

Background

Brain metastases (BM) occur in the natural course of malignant tumors in 18-40% of cases. Their management has changed considerably over the past decade thanks to the advent of Gamma knife Stereotactic Radiosurgery (GKSR).

Objective

We report our experience on Single Brain metastasis treated with (GKSR).

Methods

Patients treated by Gamma Knife stereotaxic radiosurgery (GKSR) in our institution between 2009 and 2021 for Single BM were recorded retrospectively.

Results

A total of 103 patients (n = 52; 50.5% females) were included, with a mean age of 56.33 ± 11.33. Breast (n = 39, 37.9%) and lung (n = 36, 35%) were the common original location for the primary tumors. GKSR alone without prior surgery, radiotherapy, or chemotherapy was achieved in 81.5% (n = 84). Thirteen patients (15.1%) progressed in BM volume while finding the appearance of de novo BM in 5 (5.8%) patients. The median percentage of tumor control after radiosurgery treatment was 70% (IQR: 65-78) and only 26.2% (n = 27) of patients had > 80% tumor control and stability over the median follow-up time of 5 (95% CI, 4-6) months. We found only two cases of radionecrosis (1.9%). The median survival time was 5.21 (IQR, 3-8) months. Retreatment, recursive partitioning analysis (RPA) class, and tumor stability influenced the overall survival of BM respectively (Hazard Ratio adjust (HRa)= 5.610,p = 0.045; HRa= 6.133,p = 0.031; HRa= 22.463, p = 0.036).

Conclusion

Stereotaxic Radiosurgery provides good results in terms of Overall survival with fewer neurocognitive disorders.RPA class and tumor control (stability) influenced the overall survival of single BM.

WBRT for brain metastases from non-small cell lung cancer: for whom and when?-Contemporary point of view

The incidence of brain metastases (BM) is estimated between 20% and 40% of patients with solid cancer. The most common cause of this failure is lung cancer, and in locally advanced non-small cell lung cancer (NSCLC) BM represent a common site of relapse in 30-55% cases. The basic criteria of therapeutic decision-making are based on the significant prognostic factors which are components of prognostic scores. The standard approach to treatment of BM from NSCLC include whole brain radiotherapy (WBRT) which is used as adjuvant modality after local therapy (surgery or stereotactic radiosurgery) or as primary treatment and it remains the primary modality of treatment for patients with multiple metastases. WBRT is also used in combination with systemic therapy. The aim of presented review of literature is trying to answer which patients with BM from NSCLC should receive WBRT and when it could be omitted. There were presented the aspects of application of WBRT in relation to (I) choice between WBRT or the best supportive care and (II) employment of WBRT in combination with local treatment modalities [surgical resection or stereotactic radio-surgery (SRS)] and/or with systemic therapy. According to data from literature we concluded that the most important factor that needs to be considered when assessing the suitability of a patient for WBRT is the patient's prognosis based on the Lung-molGPA score. WBRT should be applied in treatment of multiple BM from lung cancer in patients with favourable prognosis and in in patients with presence of EML4-ALK translocation before therapy with crizotinib. Whereas WBRT could be omitted in patients with poor prognosis and after primary SRS.

Brain Metastases from Uterine Cervical and Endometrial Cancer

Simple Summary

This review investigated the prevalence, clinical characteristics, clinical presentation, diagnosis, treatment, and prognosis of patients with brain metastases from uterine cervical carcinoma (CC) and uterine endometrial carcinoma (EC). The findings of this review indicate the factors that can facilitate better treatment selection and, consequently, better outcomes in patients with CC and EC.

Abstract

Reports on brain metastases (BMs) from uterine cervical carcinoma (CC) and uterine endometrial carcinoma (EC) have recently increased due to the development of massive databases and improvements in diagnostic procedures. This review separately investigates the prevalence, clinical characteristics, clinical presentation, diagnosis, treatment, and prognosis of BMs from CC and uterine endometrial carcinoma EC. For patients with CC, early-stage disease and poorly differentiated carcinoma lead to BMs, and elderly age, poor performance status, and multiple BMs are listed as poor prognostic factors. Advanced-stage disease and high-grade carcinoma are high-risk factors for BMs from EC, and multiple metastases and extracranial metastases, or unimodal therapies, are possibly factors indicating poor prognosis. There is no “most effective” therapy that has gained consensus for the treatment of BMs. Treatment decisions are based on clinical status, number of the metastases, tumor size, and metastases at distant organs. Surgical resection followed by adjuvant radiotherapy appears to be the best treatment approach to date. Stereotactic ablative radiation therapy has been increasingly associated with good outcomes in preserving cognitive functions. Despite treatment, patients died within 1 year after the BM diagnosis. BMs from uterine cancer remain quite rare, and the current evidence is limited; thus, further studies are needed.

A Phase II Multi-institutional Clinical Trial Assessing Fractionated Simultaneous In-Field Boost Radiotherapy for Brain Oligometastases

Purpose/Objective Published preclinical and phase I clinical trial data suggest that fractionated lesional radiotherapy with 60 Gy in 10 fractions can serve as an alternative approach to single fraction radiosurgical boost for brain oligometastases.  Methods and Materials A phase II clinical trial (NCT01543542) of a total of 60 Gy in 10 fractions of lesional (one to three) radiotherapy (given simultaneously with whole-brain helical tomotherapy with 30 Gy in 10 fractions) was conducted at five institutions. We hypothesized that fractionated radiotherapy would be considered unsuitable if the median overall survival (OS) was degraded by two months or if six-month intracranial control (ICC) and intracranial lesion (ILC) were inferior by 10% compared with the published RTOG 9508 results. Results A total of 87 patients were enrolled over a 4.5-year accrual period. Radiological lesion and extralesional central nervous system progression were documented in 15/87 (17%) and 11/87 (13%) patients, respectively. Median OS for all patients was 5.4 months. Six-month actuarial estimates of ICC and ILC were 78% and 89%, respectively. However, only the ILC estimate achieved statistical significance (p=0.02), demonstrating non-inferiority to the a priori historical controls (OS: p=0.09, ICC=0.31). Two patients developed suspected asymptomatic radionecrosis. Conclusions The phase II estimates of ILC were demonstrated to be non-inferior to the results of the RTOG 9508.

Selection of prescription isodose line for brain metastases treated with volumetric modulated arc radiotherapy

Purpose

To exploit the optimal prescription isodose line (IDL) for brain metastases treated with volumetric modulated arc radiotherapy (VMAT) as there is no consensus on the selection of IDL with VMAT.

Methods and materials

Eighteen patients with 20 brain tumors, who were treated with VMAT, were enrolled in this study. For each tumor of every patient, five plans were designed with IDL ranging from 50% to 90% in 10% increments. Different IDLs were obtained through adjusting the constraint parameters during planning optimization. Prescription dose (10 × 5 Gy) were identical for all plans, and the plans were compared in terms of gradient index (GI), conformity Index (CI), V26 Gy/V_PTV, and V32 Gy/V_PTV in normal brain tissue, which correlate to radiation necrosis.

Results

IDL with lowest GI has a median value of 60.0% (ranging from 50% to 80%). Except for one tumor with volume larger than 10 cc, the IDL with lowest GI varies from 50% to 70%, which depends on the shape of PTV, location, and whether the target volume is adjacent to crucial OAR. Moreover, there is no significant difference for CI with varying IDL plans. The average V26 Gy/V_PTV and V32 Gy/V_PTV in normal brain tissue 60% IDL plans are 27.3%, 31.7% lower than 90% IDL plans separately (P < 0.05). However, by further decreasing IDL from 60% to 50%, the average V26 Gy/V_PTV and V32 Gy/V_PTV may increase comparing with 60% IDL plans (P > 0.05). Furthermore, a lower IDL is found to result in higher mean dose to the target volume (P < 0.05).

Conclusions

Plans using VMAT with PTV smaller than 10 cc tend to be optimal with IDL around 60–70% for lower GI, smaller V26 Gy/V_PTV, V32 Gy/V_PTV in normal brain tissue, and higher mean dose in tumor comparing with high IDL plans which have potential benefit in reducing risk of radiation necrosis and increasing the local control. However, IDL lower than 60% is not recommended for the disadvantage of increasing V26 Gy/V_PTV and V32 Gy/V_PTV in normal brain tissue.

Stereotactic Radiosurgery to More Than 10 Brain Metastases: Evidence to Support the Role of Radiosurgery for Ideal Hippocampal Sparing in the Treatment of Multiple Brain Metastases

BACKGROUND

Brain metastases are a common occurrence, with literature supporting the treatment of a limited number of brain metastases with stereotactic radiosurgery (SRS), as opposed to whole brain radiotherapy (WBRT). Less well understood is the role of SRS in patients with ≥10 brain metastases.

METHODS

Patients treated with SRS to ≥10 brain metastases without concurrent WBRT between March 1999 and December 2016 were reviewed. Analysis was performed for overall survival, treated lesion freedom from progression (FFP), freedom from new metastases (FFNMs), and adverse radiation effect. Hippocampal volumes were retrospectively generated in patients treated with up-front SRS for evaluation of dose volume metrics.

RESULTS

A total of 143 patients were identified with 75 patients having up-front SRS and 68 patients being treated as salvage therapy after prior WBRT. The median number of lesions per patient was 13 (interquartile range [IQR], 11-17). Median total volume of treatment was 4.1 cm³ (IQR, 2.0-9.9 cm³). The median 12-month FFP for up-front and salvage treatment was 96.8% (95% confidence interval [CI], 95.5-98.1) and 83.6% (95% CI, 79.9-87.5), respectively (P < 0.001). Twelve-month FFNMs for up-front and salvage SRS was 18.8% (95% CI, 10.9-32.3) versus 19.2% (95% CI, 9.7-37.8), respectively (P = 0.90). The mean hippocampal dose was 150 cGy (IQR, 100-202 cGy).

CONCLUSIONS

Excellent rates of local control can be achieved when treating patients with >10 intracranial metastases either in the up-front or salvage setting. Hippocampal sparing is readily achievable with expected high rates of new metastatic lesions in treated patients.

Superior Prognostic Value of Cumulative Intracranial Tumor Volume Relative to Largest Intracranial Tumor Volume for Stereotactic Radiosurgery-Treated Brain Metastasis Patients

BACKGROUND

Two intracranial tumor volume variables have been shown to prognosticate survival of stereotactic-radiosurgery-treated brain metastasis patients: the largest intracranial tumor volume (LITV) and the cumulative intracranial tumor volume (CITV).

OBJECTIVE

To determine whether the prognostic value of the Scored Index for Radiosurgery (SIR) model can be improved by replacing one of its components-LITV-with CITV.

METHODS

We compared LITV and CITV in terms of their survival prognostication using a series of multivariable models that included known components of the SIR: age, Karnofsky Performance Score, status of extracranial disease, and the number of brain metastases. Models were compared using established statistical measures, including the net reclassification improvement (NRI > 0) and integrated discrimination improvement (IDI). The analysis was performed in 2 independent cohorts, each consisting of ∼3000 patients.

RESULTS

In both cohorts, CITV was shown to be independently predictive of patient survival. Replacement of LITV with CITV in the SIR model improved the model's ability to predict 1-yr survival. In the first cohort, the CITV model showed an NRI > 0 improvement of 0.2574 (95% confidence interval [CI] 0.1890-0.3257) and IDI of 0.0088 (95% CI 0.0057-0.0119) relative to the LITV model. In the second cohort, the CITV model showed a NRI > 0 of 0.2604 (95% CI 0.1796-0.3411) and IDI of 0.0051 (95% CI 0.0029-0.0073) relative to the LITV model.

CONCLUSION

After accounting for covariates within the SIR model, CITV offers superior prognostic value relative to LITV for stereotactic radiosurgery-treated brain metastasis patients.

Re-Irradiation of Brain Metastases and Metastatic Spinal Cord Compression: Clinical Practice Suggestions

The recent improvements of therapeutic approaches in oncology have allowed a certain number of patients with advanced disease to survive much longer than in the past. So, the number of cases with brain metastases and metastatic spinal cord compression has increased, as has the possibility of developing a recurrence in areas of the central nervous system already treated with radiotherapy.

Clinicians are reluctant to perform re-irradiation of the brain, because of the risk of severe side effects. The tolerance dose for the brain to a single course of radiotherapy is 50–60 Gy in 2 Gy daily fractions. New metastases appear in 22–73% of the cases after whole brain radiotherapy, but the percentage of re-irradiated patients is 3–10%. An accurate selection must be made before giving an indication to re-irradiation. Patients with Karnofsky performance status >70, age <65 years, controlled primary and no extracranial metastases are those with the best prognosis. The absence of extracranial disease was the most significant factor in conditioning survival, and maximum tumor diameter was the only variable associated with an increased risk of unacceptable acute and/or chronic neurotoxicity. Re-treatment of brain metastases can be done with whole brain radiotherapy, stereotactic radiosurgery or fractionated stereotactic radiotherapy. Most patients had no relevant radiation-induced toxicity after a second course of whole brain radiotherapy or stereotactic radiosurgery. There are few data on fractionated stereotactic radiotherapy in the re-irradiation of brain metastases.

In general, the incidence of an “in-field” recurrence of spinal metastasis varies from 2.5–11% of cases and can occur 2–40 months after the first radiotherapy cycle. Radiation-induced myelopathy can occur months or years (6 months-7 years) after radiotherapy, and the pathogenesis remains obscure. Higher radiotherapy doses, larger doses per fraction, and previous exposure to radiation could be associated with a higher probability of developing radiation-induced myelopathy. Experimental data indicate that also the total dose of the first and second radiotherapy, interval to re-treatment, length of the irradiated spinal cord, and age of the treated animals influence the risk of radiation-induced myelopathy. An α/β ratio of 1.9–3 Gy could be generally the reference value for fractionated radiotherapy. However, when fraction sizes are up to 5 Gy, the linear-quadratic equation become a less valid model. The early diagnosis of relapse is crucial in conditioning response to re-treatment.

Multi-Institutional Dosimetric Evaluation of Modern Day Stereotactic Radiosurgery (SRS) Treatment Options for Multiple Brain Metastases

Purpose/Objectives: There are several popular treatment options currently available for stereotactic radiosurgery (SRS) of multiple brain metastases: ⁶⁰Co sources and cone collimators around a spherical geometry (GammaKnife), multi-aperture dynamic conformal arcs on a linac (BrainLab Elements™ v1.5), and volumetric arc therapy on a linac (VMAT) calculated with either the conventional optimizer or with the Varian HyperArc™ solution. This study aimed to dosimetrically compare and evaluate the differences among these treatment options in terms of dose conformity to the tumor as well as dose sparing to the surrounding normal tissues. Methods and Materials: Sixteen patients and a total of 112 metastases were analyzed. Five plans were generated per patient: GammaKnife, Elements, HyperArc-VMAT, and two Manual-VMAT plans to evaluate different treatment planning styles. Manual-VMAT plans were generated by different institutions according to their own clinical planning standards. The following dosimetric parameters were extracted: RTOG and Paddick conformity indices, gradient index, total volume of brain receiving 12Gy, 6Gy, and 3Gy, and maximum doses to surrounding organs. The Wilcoxon signed rank test was applied to evaluate statistically significant differences (p < 0.05). Results: For targets ≤ 1 cm, GammaKnife, HyperArc-VMAT and both Manual-VMAT plans achieved comparable conformity indices, all superior to Elements. However, GammaKnife resulted in the lowest gradient indices at these target sizes. HyperArc-VMAT performed similarly to GammaKnife for V_12Gy parameters. For targets ≥ 1 cm, HyperArc-VMAT and Manual-VMAT plans resulted in superior conformity vs. GammaKnife and Elements. All SRS plans achieved clinically acceptable organs-at-risk dose constraints. Beam-on times were significantly longer for GammaKnife. Manual-VMAT_A and Elements resulted in shorter delivery times relative to Manual-VMAT_B and HyperArc-VMAT. Conclusion: The study revealed that Manual-VMAT and HyperArc-VMAT are capable of achieving similar low dose brain spillage and conformity as GammaKnife, while significantly minimizing beam-on time. For targets smaller than 1 cm in diameter, GammaKnife still resulted in superior gradient indices. The quality of the two sets of Manual-VMAT plans varied greatly based on planner and optimization constraint settings, whereas HyperArc-VMAT performed dosimetrically superior to the two Manual-VMAT plans.

Whole Brain Radiation Therapy Plus Stereotactic Radiosurgery in the Treatment of Brain Metastases Leading to Improved Survival in Patients With Favorable Prognostic Factors

Background: Significantly better local control is achieved with combination of whole brain radiotherapy and stereotactic radiosurgery in the treatment of multiple brain metastases. However, no survival benefit was reported from this advantage in local control. Objective: The objective of this study was to review the available evidence whether better local control achieved with whole brain radiotherapy plus stereotactic radiosurgery leads to any benefit in survival in patients with favorable prognostic factors. Methods and Materials: Electronic databases (PubMed, MEDLINE, and Cochrane Library) were searched until Oct 2018 to identify studies published in English that compared efficacy of whole brain radiotherapy plus stereotactic radiosurgery vs. whole brain radiotherapy alone or stereotactic radiosurgery alone in patients with brain metastases stratified on prognostic indices (Recursive Partitioning Analysis and Diagnosis-Specific Graded Prognostic Assessment). Primary outcome was survival. Results: Five studies (n = 2728) were identified, 3 secondary analyses of the previously published RCTs and 2 retrospective studies, meeting the inclusion criteria. whole brain radiotherapy plus stereotactic radiosurgery showed improved survival in brain metastatic cancer patients with better prognostic factors particularly when compared to whole brain radiotherapy only. Its survival advantage over stereotactic radiosurgery only was limited to non-small cell lung cancer primary tumor histology. Conclusions: Whole brain radiotherapy in combination with stereotactic radiosurgery may improve survival and could be recommended selectively in patients with favorable prognostic factors particularly in comparison to whole brain radiotherapy only.

Targeted therapy of brain metastases: latest evidence and clinical implications

Brain metastases (BM) occur in 20-40% of patients with cancer and 60-75% of patients with BM become symptomatic. Due to an aging population and advances in the treatment of primary cancers, patients are living longer and are more likely to experience complications from BM. The diagnosis of BM drastically worsens long-term survival rates, with multiple metastases being a poor prognostic factor. Until recently, the mainstay of treatment consisted of stereotactic radiosurgery (SRS), surgical resection, whole brain radiation therapy (WBRT), or a combination of these modalities. Systemic chemotherapy has been felt largely ineffective in the treatment of BM due to the presence of the blood-brain barrier (BBB), which includes efflux pumps on brain capillaries. Over the past decade however, researchers have identified therapeutic agents that are able to cross the BBB. These findings could make a multimodality treatment approach possible, consisting of surgery, radiation, immunotherapy, and targeted therapy, which could lead to better disease control in this patient population and prolong survival. In this review, we discuss present evidence on available targeted therapies and their role in the treatment of BM from primary tumors with the highest prevalence of central nervous system (CNS) involvement, specifically non-small cell lung cancer (NSCLC), breast cancer melanoma, and renal cell carcinoma.

Whole brain radiation therapy (WBRT) alone versus WBRT and radiosurgery for the treatment of brain metastases

BACKGROUND

Historically, whole brain radiation therapy (WBRT) has been the main treatment for brain metastases. Stereotactic radiosurgery (SRS) delivers high-dose focused radiation and is being increasingly utilized to treat brain metastases. The benefit of adding SRS to WBRT is unclear. This is an updated version of the original Cochrane Review published in Issue 9, 2012.

OBJECTIVES

To assess the efficacy of WBRT plus SRS versus WBRT alone in the treatment of adults with brain metastases.

SEARCH METHODS

For the original review, in 2009 we searched the following electronic databases: CENTRAL, MEDLINE, Embase, and CancerLit in order to identify trials for inclusion in this review. For the first update the searches were updated in May 2012.For this update, in May 2017 we searched CENTRAL, MEDLINE, and Embase in order to identify trials for inclusion in the review.

SELECTION CRITERIA

We restricted the review to randomized controlled trials (RCTs) that compared use of WBRT plus SRS versus WBRT alone for upfront treatment of adults with newly diagnosed metastases (single or multiple) in the brain resulting from any primary, extracranial cancer.

DATA COLLECTION AND ANALYSIS

We used the generic inverse variance method, random-effects model in Review Manager 5 for the meta-analysis.

MAIN RESULTS

We identified three studies and one abstract for inclusion but we could only include two studies, with a total of 358 participants in a meta-analysis. This found no difference in overall survival (OS) between the WBRT plus SRS and WBRT alone groups (hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.65 to 1.02; 2 studies, 358 participants; moderate-quality evidence). For participants with one brain metastasis median survival was significantly longer in the WBRT plus SRS group (6.5 months) versus WBRT group (4.9 months; P = 0.04). Participants in the WBRT plus SRS group had decreased local failure compared to participants who received WBRT alone (HR 0.27, 95% CI 0.14 to 0.52; 2 studies, 129 participants; moderate-quality evidence). Furthermore, we observed an improvement in performance status scores and decrease in steroid use in the WBRT plus SRS group (risk ratio (RR) 0.64 CI 0.42 to 0.97; 1 study, 118 participants; low-quality evidence). Unchanged or improved Karnofsky Performance Scale (KPS) at six months was seen in 43% of participants in the combined therapy group versus only 28% in the WBRT-alone group (RR 0.78 CI 0.61 to 1.00; P value = 0.05; 1 study, 118 participants; low-quality evidence). Overall, risk of bias in the included studies was unclear.

AUTHORS' CONCLUSIONS

Since the last version of this review we have identified one new study that met the inclusion criteria. However, due to a lack of data from this study we were not able to include it in a meta-analysis. Given the unclear risk of bias in the included studies, the results of this analysis have to be interpreted with caution. In our analysis of all included participants, SRS plus WBRT did not show a survival benefit over WBRT alone. However, performance status and local control were significantly better in the SRS plus WBRT group. Furthermore, significantly longer OS was reported in the combined treatment group for recursive partitioning analysis (RPA) Class I patients as well as patients with single metastasis. Most of our outcomes of interest were graded as moderate-quality evidence according to the GRADE criteria and the risk of bias in the majority of included studies was mostly unclear.

A Bayesian network meta-analysis of whole brain radiotherapy and stereotactic radiotherapy for brain metastasis

This study was conducted to compare the effects of whole brain radiotherapy (WBRT) and stereotactic radiotherapy (SRS) in treatment of brain metastasis.A systematical retrieval in PubMed and Embase databases was performed for relative literatures on the effects of WBRT and SRS in treatment of brain metastasis. A Bayesian network meta-analysis was performed by using the ADDIS software. The effect sizes included odds ratio (OR) and 95% confidence interval (CI). A random effects model was used for the pooled analysis for all the outcome measures, including 1-year distant control rate, 1-year local control rate, 1-year survival rate, and complication. The consistency was tested by using node-splitting analysis and inconsistency standard deviation. The convergence was estimated according to the Brooks-Gelman-Rubin method.A total of 12 literatures were included in this meta-analysis. WBRT + SRS showed higher 1-year distant control rate than SRS. WBRT + SRS was better for the 1-year local control rate than WBRT. SRS and WBRT + SRS had higher 1-year survival rate than the WBRT. In addition, there was no difference in complication among the three therapies.Comprehensively, WBRT + SRS might be the choice of treatment for brain metastasis.

Comparison of WBRT alone, SRS alone, and their combination in the treatment of one or more brain metastases: Review and meta-analysis

Whole brain radiotherapy has been a standard treatment of brain metastases. Stereotactic radiosurgery provides more focal and aggressive radiation and normal tissue sparing but worse local and distant control. This meta-analysis was performed to assess and compare the effectiveness of whole brain radiotherapy alone, stereotactic radiosurgery alone, and their combination in the treatment of brain metastases based on randomized controlled trial studies. Electronic databases (PubMed, MEDLINE, Embase, and Cochrane Library) were searched to identify randomized controlled trial studies that compared treatment outcome of whole brain radiotherapy and stereotactic radiosurgery. This meta-analysis was performed using the Review Manager (RevMan) software (version 5.2) that is provided by the Cochrane Collaboration. The data used were hazard ratios with 95% confidence intervals calculated for time-to-event data extracted from survival curves and local tumor control rate curves. Odds ratio with 95% confidence intervals were calculated for dichotomous data, while mean differences with 95% confidence intervals were calculated for continuous data. Fixed-effects or random-effects models were adopted according to heterogeneity. Five studies (n = 763) were included in this meta-analysis meeting the inclusion criteria. All the included studies were randomized controlled trials. The sample size ranged from 27 to 331. In total 202 (26%) patients with whole brain radiotherapy alone, 196 (26%) patients receiving stereotactic radiosurgery alone, and 365 (48%) patients were in whole brain radiotherapy plus stereotactic radiosurgery group. No significant survival benefit was observed for any treatment approach; hazard ratio was 1.19 (95% confidence interval: 0.96-1.43, p = 0.12) based on three randomized controlled trials for whole brain radiotherapy only compared to whole brain radiotherapy plus stereotactic radiosurgery and hazard ratio was 1.03 (95% confidence interval: 0.82-1.29, p = 0.81) for stereotactic radiosurgery only compared to combined approach. Local control was best achieved when whole brain radiotherapy was combined with stereotactic radiosurgery. Hazard ratio 2.05 (95% confidence interval: 1.36-3.09, p = 0.0006) and hazard ratio 1.84 (95% confidence interval: 1.26-2.70, p = 0.002) were obtained from comparing whole brain radiotherapy only and stereotactic radiosurgery only to whole brain radiotherapy + stereotactic radiosurgery, respectively. No difference in adverse events for treatment difference; odds ratio 1.16 (95% confidence interval: 0.77-1.76, p = 0.48) and odds ratio 0.92 (95% confidence interval: 0.59-1.42, p = 71) for whole brain radiotherapy + stereotactic radiosurgery versus whole brain radiotherapy only and whole brain radiotherapy + stereotactic radiosurgery versus stereotactic radiosurgery only, respectively. Adding stereotactic radiosurgery to whole brain radiotherapy provides better local control as compared to whole brain radiotherapy only and stereotactic radiosurgery only with no difference in radiation related toxicities.

A Single-Institution Analysis of 126 Patients Treated with Stereotactic Radiosurgery for Brain Metastases

Background

The objective of this study was to report our institutional experience with Gamma Knife^® Radiosurgery (GKRS) in the treatment of patients with brain metastases.

Methods

Retrospectively collected demographic and clinical data on 126 patients with intracranial metastases were reviewed. The patients in our study underwent GKRS at Vidant Medical Center between 2009 and 2014. Kaplan–Meier curves were used to compare survival based on clinical characteristics for univariate analysis, and a Cox proportional hazards model was used for multivariate analysis.

Results

The median age of the patient population was 62 years. Medicare patients constituted 51% of our patient cohort and Medicaid patients 15%. The most common tumor histologies were non-small cell lung cancer (50%), breast cancer (12.7%), and melanoma (11.9%). The median overall survival time for all patients was 5.8 months. Patients with breast cancer had the longest median survival time of 9.15 months, while patients with melanoma had the shortest median survival time of 2.86 months. On univariate analysis, the following factors were predictors for improved overall survival, ECOG score 0 or 1 vs. 2 or greater (17.0 vs. 1.8 months, p < 0.001), controlled extracranial disease vs. progressive extracranial disease (17.4 vs. 4.6 months, p = 0.0001), recursive partitioning analysis Stage I vs. II–III (18.2 vs. 6.2 months, p < 0.007), multiple GKRS treatments (p = 0.002), prior brain metastasectomy (p = 0.012), and prior chemotherapy (p = 0.021). Age, ethnicity, gender, previous external beam radiation therapy, number of brain metastases, and hemorrhagic vs. non-hemorrhagic tumors were not predictors of longer median survival time. Number of metastatic brain lesions of 1–3 vs. ≥4 (p = 0.051) and insurance status of Medicare/Medicaid vs. commercial insurance approached significance (13.7 vs. 6.8 months, p = 0.08). On multivariate analysis, ECOG performance status 0–1 (p < 0.001), multiple GKRS treatments (p = 0.003), and control of extracranial disease (p = 0.001) remained significant predictors of survival.

Conclusion

ECOG score, control of extracranial disease, and multiple GKRS treatments are predictors of longer median survival following GKRS in our patient population. GKRS is an effective treatment for brain metastases, but these factors may be considered in patient selection for GKRS.

Predictive factors of early distant brain failure after gamma knife radiosurgery alone in patients with brain metastases of non-small-cell lung cancer

The objective of this study was to elucidate the predictive factors for early distant brain failure in patients with brain metastases of non-small-cell lung cancer (NSCLC) who were treated with gamma knife radiosurgery (GKRS) without previous whole-brain radiotherapy (WBRT) or surgery. We retrospectively reviewed clinical and imaging data of 459 patients with brain metastases of NSCLC who underwent GKRS from June 2008 to December 2013. The primary end-point was early distant brain failure, defined as the detection of newly developed metastatic lesions on magnetic resonance imaging (MRI) 3 months after GKRS. Factors such as tumor pathology subtype, concurrent systemic chemotherapy, epidermal growth factor receptor (EGFR) mutation status, use of EGFR tyrosine kinase inhibitors (TKIs), systemic disease status, presence of a metastatic lesion only in delayed MRI, and volume and number of metastases were analyzed. There were no statistically significant differences with respect to pathologic subtype, concurrent systemic chemotherapy, EGFR mutation, and early distant brain failure. Patients treated with EGFR-TKIs (p = 0.004), with a stable systemic disease status (p = 0.028) and 3 or fewer brain lesions (p = 0.000) experienced a significantly lower incidence of early distant brain failure. This study suggests that GKRS alone could be considered for patients treated with EGFR-TKIs who have a stable systemic disease status and 3 or fewer brain lesions. WBRT should be considered for other patients.

Methods and results of locoregional treatment of brain metastases in patients with non-small cell lung cancer

This article presents methods and results of surgery and radiotherapy of brain metastases from non-small cell lung cancer (BMF-NSCLC). Patients with single BMF-NSCLC, with Karnofsky score ≥ 70 and controlled extracranial disease are the best candidates for surgery. Stereotactic radiosurgery (SRS) is recommended in patients with 1-3 BMF-NSCLC below 3-3.5 cm, with minor neurological symptoms, located in parts of the brain not accessible to surgery, with controlled extracranial disease. Whole brain radiotherapy (WBRT) following SRS reduces the risk of local relapse; in selected patients median survival reaches more than 10 months. Whole brain radiotherapy alone is a treatment in patients with multiple metastases, poor performance status, uncontrolled extracranial disease, disqualified from surgery or SRS with median survival 3 to 6 months. There is no doubt that there are patients with BMF-NSCLC who should receive only the best supportive care. There is a debate in the literature on how to select these patients.

Recursive Partitioning Analysis of Prognostic Factors for Patients with Four or More Intracranial Metastases Treated with Radiosurgery

The purpose of this study was to devise a new recursive partitioning analysis (RPA) of patients with four or more intracranial metastases treated with a single radiosurgery procedure to identify a class of patients with extended survival. 205 patients underwent Gamma Knife radiosurgery for four or more intracranial metastases (median = 5, range 4–18) during one session. The median total treatment volume was 6.8 cc (range 0.6–51.0 cc). Radiosurgery was used as sole management (17% of patients), or in combination with WB-RT (46%), or after failure of WB-RT (38%). The median marginal radiosurgery dose was 16 Gy (range 12–20 Gy). RPA assessed the effects of age, Karnofsky >70, extracranial disease, visceral metastases, number of metastases, total treatment volume, history of breast and melanoma primaries on survival. The median overall survival after radiosurgery for all patients was 8 months. RPA identified a favorable subgroup of 78 patients (43% of the series) with a total treatment volume <7 cc and < 7 brain metastases (Class 1), with a median survival of 13 months. This subgroup's survival was significantly better (p <0.00005) than the remaining patients (Class 2) (n=111) with a median survival of 6 months. In conclusion, RPA of multiple brain metastasis patients identified 2 distinct cohorts of patients. Class 1 patients have a total treatment volume <7 cc and < 7 metastases (4–6) with favorable survival after Radiosurgery and Class 2 patients have a total treatment volume ≥ 7 cc and/or ≥ 7 metastases and have a significantly poorer survival.

Normal Brain Sparing With Increasing Number of Beams and Isocenters in Volumetric-Modulated Arc Beam Radiosurgery of Multiple Brain Metastases

Recent studies have reported about the application of volumetric-modulated arc radiotherapy in the treatment of multiple brain metastases. One of the key concerns for these radiosurgical treatments lies in the integral dose within the normal brain tissue, as it has been shown to increase with increasing number of brain tumors treated. In this study, we investigate the potential to improve normal brain tissue sparing specific to volumetric-modulated arc radiotherapy by increasing the number of isocenters and arc beams. Adopting a multi-institutional benchmark study protocol of planning multiple brain metastases via a radiosurgical apparatus, a flattening filter-free TrueBeam RapidArc delivery system (Varian Oncology, Palo Alto, California) was used for a volumetric-modulated arc radiotherapy treatment planning study, where treatment plans for target combinations of N = 1, 3, 6, 9, and 12 targets were developed with increasing numbers of isocenters and arc beams. The treatment plans for each target combination were compared dosimetrically among each other and against the reference Gamma Knife treatment plan from the original benchmark study. We observed that as the number of isocenters or arc beams increased, the normal brain isodose volumes such as 12- to 4-Gy on average decreased by up to 15% for all the studied cases. However, when the best volumetric-modulated arc radiotherapy normal brain isodose volumes were compared against the corresponding reference Gamma Knife values, volumetric-modulated arc radiotherapy remained 100% to 200% higher than those of Gamma Knife for all target combinations. The study results, particularly for the solitary (N = 1) metastases case, directly challenged the general notion of dose equivalence among current radiosurgical modalities. In conclusion, multiple isocenter and multiple arc beam delivery solutions are capable of decreasing normal brain irradiation exposure for volumetric-modulated arc radiotherapy. However, there is further technological development in need for volumetric-modulated arc radiotherapy before similar dosimetric treatment plans could be achievable when compared to Gamma Knife radiosurgery.

Tumor progression in patients receiving adjuvant whole-brain radiotherapy vs localized radiotherapy after surgical resection of brain metastases

BACKGROUND

Surgery followed by adjuvant radiotherapy is a well-established treatment paradigm for brain metastases.

OBJECTIVE

To examine the effect of postsurgical whole-brain radiotherapy (WBRT) or localized radiotherapy (LRT), including stereotactic radiosurgery and intraoperative radiotherapy, on the rate of recurrence both local and distal to the resection site in the treatment of brain metastases.

METHODS

We retrospectively identified patients who underwent surgery for brain metastasis at the Cleveland Clinic between 2004 and 2012. Institutional review board-approved chart review was conducted, and patients who had radiation before surgery, who had nonmetastatic lesions, or who lacked postadjuvant imaging were excluded.

RESULTS

The final analysis included 212 patients. One hundred fifty-six patients received WBRT, 37 received stereotactic radiosurgery only, and 19 received intraoperative radiotherapy. One hundred forty-six patients were deceased, of whom 60 (41%) died with no evidence of recurrence. Competing risks methodology was used to test the association between adjuvant modality and progression. Multivariable analysis revealed no significant difference in the rate of recurrence at the resection site (hazard ratio [HR] 1.46, P = .26) or of unresected, radiotherapy-treated lesions (HR 1.70, P = .41) for LRT vs WBRT. Patients treated with LRT had an increased hazard of the development of new lesions (HR 2.41, P < .001) and leptomeningeal disease (HR 2.45, P = .04). Median survival was 16.5 months and was not significantly different between groups.

CONCLUSION

LRT as adjuvant treatment to surgical resection of brain metastases is associated with an increased rate of development of new distant metastases and leptomeningeal disease compared with WBRT, but not with recurrence at the resection site or of unresected lesions treated with radiation.

Characteristics and treatments of large cystic brain metastasis: radiosurgery and stereotactic aspiration

Brain metastasis represents one of the most common causes of intracranial tumors in adults, and the incidence of brain metastasis continues to rise due to the increasing survival of cancer patients. Yet, the development of cystic brain metastasis remains a relatively rare occurrence. In this review, we describe the characteristics of cystic brain metastasis and evaluate the combined use of stereotactic aspiration and radiosurgery in treating large cystic brain metastasis. The results of several studies show that stereotactic radiosurgery produces comparable local tumor control and survival rates as other surgery protocols. When the size of the tumor interferes with radiosurgery, stereotactic aspiration of the metastasis should be considered to reduce the target volume as well as decreasing the chance of radiation induced necrosis and providing symptomatic relief from mass effect. The combined use of stereotactic aspiration and radiosurgery has strong implications in improving patient outcomes.

Cost-effectiveness of stereotactic radiosurgery with and without whole-brain radiotherapy for the treatment of newly diagnosed brain metastases

Object

Stereotactic radiosurgery (SRS) alone is increasingly used in patients with newly diagnosed brain metastases. Stereotactic radiosurgery used together with whole-brain radiotherapy (WBRT) reduces intracranial failure rates, but this combination also causes greater neurocognitive toxicity and does not improve survival. Critics of SRS alone contend that deferring WBRT results in an increased need for salvage therapy and in higher costs. The authors compared the cost-effectiveness of treatment with SRS alone, SRS and WBRT (SRS+WBRT), and surgery followed by SRS (S+SRS) at the authors' institution.

Methods

The authors retrospectively reviewed the medical records of 289 patients in whom brain metastases were newly diagnosed and who were treated between May 2001 and December 2007. Overall survival curves were plotted using the Kaplan-Meier method. Multivariate proportional hazards analysis (MVA) was used to identify factors associated with overall survival. Survival data were complete for 96.2% of patients, and comprehensive data on the resource use for imaging, hospitalizations, and salvage therapies were available from the medical records. Treatment costs included the cost of initial and all salvage therapies for brain metastases, hospitalizations, management of complications, and imaging. They were computed on the basis of the 2007 Medicare fee schedule from a payer perspective. Average treatment cost and average cost per month of median survival were compared. Sensitivity analysis was performed to examine the impact of variations in key cost variables.

Results

No significant differences in overall survival were observed among patients treated with SRS alone, SRS+WBRT, or S+SRS with respective median survival of 9.8, 7.4, and 10.6 months. The MVA detected a significant association of overall survival with female sex, Karnofsky Performance Scale (KPS) score, primary tumor control, absence of extracranial metastases, and number of brain metastases. Salvage therapy was required in 43% of SRS-alone and 26% of SRS+WBRT patients (p < 0.009). Despite an increased need for salvage therapy, the average cost per month of median survival was $2412 per month for SRS alone, $3220 per month for SRS+WBRT, and $4360 per month for S+SRS (p < 0.03). Compared with SRS+WBRT, SRS alone had an average incremental cost savings of $110 per patient. Sensitivity analysis confirmed that the average treatment cost of SRS alone remained less than or was comparable to SRS+WBRT over a wide range of costs and treatment efficacies.

Conclusions

Despite an increased need for salvage therapy, patients with newly diagnosed brain metastases treated with SRS alone have similar overall survival and receive more cost-effective care than those treated with SRS+WBRT. Compared with SRS+WBRT, initial management with SRS alone does not result in a higher average cost.

Whole brain radiotherapy combined with stereotactic radiotherapy versus stereotactic radiotherapy alone for brain metastases: a meta-analysis

AIM

This study was to evaluate the effect of whole brain radiation (WBRT) combined with stereotactic radiotherapy (SRS) versus stereotactic radiotherapy alone for patients with brain metastases using a meta- analysis.

MATERIALS AND METHODS

We searched PubMed, EMBASE, Cochrane Library from their inception up to October 2013. Randomized controlled trials involving whole brain radiation combined with stereotactic radiotherapy versus stereotactic radiotherapy alone for brain metastases were included. Statistical analyses were performed using RevMan5.2 software.

RESULTS

Four randomized controlled trials including 903 patients were included. The meta-analysis showed statistically significant lowering of the local recurrence rate (OR=0.29, 95%CI: 0.17~0.49), new brain metastasis rate (OR=0.45, 95%CI: 0.28~0.71) and symptomatic late neurologic radiation toxicity rate (OR=3.92, 95%CI: 1.37~11.20) in the combined group. No statistically significant difference existed in the 1-year survival rate (OR=0.78, 95%CI: 0.60~1.03).

CONCLUSIONS

The results indicate that whole brain radiotherapy combined with stereotactic radiotherapy has advantages in local recurrence and new brain metastasis rates, but stereotactic radiotherapy alone is associated with better neurological function. However, as the samples included were not large, more high-quality, large-sample size studies are necessary for confirmation.

Stereotactic radiosurgery (SRS) for brain metastases: a systematic review

In many patients with brain metastases, the primary therapeutic aim is symptom palliation and maintenance of neurologic function, but in a subgroup, long-term survival is possible. Local control in the brain, and absent or controlled extracranial sites of disease are prerequisites for favorable survival. Stereotactic radiosurgery (SRS) is a focal, highly precise treatment option with a long track record. Its clinical development and implementation by several pioneering institutions eventually rendered possible cooperative group randomized trials. A systematic review of those studies and other landmark studies was undertaken. Most clinicians are aware of the potential benefits of SRS such as a short treatment time, a high probability of treated-lesion control and, when adhering to typical dose/volume recommendations, a low normal tissue complication probability. However, SRS as sole first-line treatment carries a risk of failure in non-treated brain regions, which has resulted in controversy around when to add whole-brain radiotherapy (WBRT). SRS might also be prescribed as salvage treatment in patients relapsing despite previous SRS and/or WBRT. An optimal balance between intracranial control and side effects requires continued research efforts.

Decision analysis of stereotactic radiation surgery versus stereotactic radiation surgery and whole-brain radiation therapy for 1 to 3 brain metastases

PURPOSE

Although whole-brain radiation therapy (WBRT) is effective for controlling intracranial disease, it is also associated with neurocognitive side effects. It is unclear whether a theoretically improved quality of life after stereotactic radiation surgery (SRS) alone relative to that after SRS with adjuvant WBRT would justify the omission of WBRT, given the higher risk of intracranial failure. This study compares SRS alone with SRS and WBRT, to evaluate the theoretical benefits of intracranial tumor control with adjuvant WBRT against its possible side effects, using quality-adjusted life expectancy (QALE) as a primary endpoint.

METHODS AND MATERIALS

A Markov decision analysis model was used to compare QALE in a cohort of patients with 1 to 3 brain metastases and Karnofsky performance status of at least 70. Patients were treated with SRS alone or with SRS immediately followed by WBRT. Patients treated with SRS alone underwent surveillance magnetic resonance imaging and received salvage WBRT if they developed intracranial relapse. All patients whose cancer relapsed after WBRT underwent simulation as dying of intracranial progression. Model parameters were estimated from published literature.

RESULTS

Treatment with SRS yielded 6.2 quality-adjusted life months (QALMs). The addition of initial WBRT reduced QALE by 1.2 QALMs. On one-way sensitivity analysis, the model was sensitive only to a single parameter, the utility associated with the state of no evidence of disease after SRS alone. At values greater than 0.51, SRS alone was preferred.

CONCLUSIONS

In general, SRS alone is suggested to have improved quality of life in patients with 1 to 3 brain metastases compared to SRS and immediate WBRT. Our results suggest that immediate treatment with WBRT after SRS can be reserved for patients who would have a poor performance status regardless of treatment. These findings are stable under a wide range of assumptions.

It Is Time to Reevaluate the Management of Patients With Brain Metastases

There are many elements to the science that drives the clinical care of patients with brain metastases. Although part of an understanding that continues to evolve, a number of key historical misconceptions remain that commonly drive physicians' and researchers' attitudes and approaches. By understanding how these relate to current practice, we can better comprehend our available science to provide both better research and care. These past misconceptions include: Misconception 1: Once a primary cancer spreads to the brain, the histology of that primary tumor does not have much impact on response to chemotherapy, sensitivity to radiation, risk of further brain relapse, development of additional metastatic lesions, or survival. All tumor primary histologies are the same once they spread to the brain. They are the same in terms of the number of tumors, radiosensitivity, chemoresponsiveness, risk of further brain relapse, and survival. Misconception 2: The number of brain metastases matters. This number matters in terms of subsequent brain relapse, survival, and cognitive dysfunction; the precise number of metastases can also be used as a limit in determining which patients might be eligible for a particular treatment option. Misconception 3: Cancer in the brain is always a diffuse problem due to the presence of micrometastases. Misconception 4: Whole-brain radiation therapy invariably causes disabling cognitive dysfunction if a patient lives long enough. Misconception 5: Most brain metastases are symptomatic. Thus, it is not worth screening patients for brain metastases, especially because the impact on survival is minimal. The conduct and findings of past clinical research have led to conceptions that affect clinical care yet appear limiting.

Current approaches to the treatment of metastatic brain tumours

Metastatic tumours involving the brain overshadow primary brain neoplasms in frequency and are an important complication in the overall management of many cancers. Importantly, advances are being made in understanding the molecular biology underlying the initial development and eventual proliferation of brain metastases. Surgery and radiation remain the cornerstones of the therapy for symptomatic lesions; however, image-based guidance is improving surgical technique to maximize the preservation of normal tissue, while more sophisticated approaches to radiation therapy are being used to minimize the long-standing concerns over the toxicity of whole-brain radiation protocols used in the past. Furthermore, the burgeoning knowledge of tumour biology has facilitated the entry of systemically administered therapies into the clinic. Responses to these targeted interventions have ranged from substantial toxicity with no control of disease to periods of useful tumour control with no decrement in performance status of the treated individual. This experience enables recognition of the limits of targeted therapy, but has also informed methods to optimize this approach. This Review focuses on the clinically relevant molecular biology of brain metastases, and summarizes the current applications of these data to imaging, surgery, radiation therapy, cytotoxic chemotherapy and targeted therapy.

Survival outcomes after whole brain radiation therapy and/or stereotactic radiosurgery for cancer patients with metastatic brain tumors in Korea: a systematic review

AIM

To compare survival outcomes after whole brain radiation therapy (WBRT), stereotactic radiosurgery (SRS), and WBRT plus SRS combination therapy in Korea, by performing a quantitative systematic review.

MATERIALS AND METHODS

We searched 10 electronic databases for reports on Korean patients treated with WBRT or SRS for brain metastases published prior to July 2010. Independent reviewers screened all articles and extracted the data. When a Kaplan-Meier survival curve was available, median survival time and standard errors were calculated. Summary estimates for the outcomes in each study were calculated using the inverse variance random-effects method.

RESULTS

Among a total of 2,761 studies, 20 studies with Korean patients (n=1,053) were identified. A combination of 12 studies (n=566) with WBRT outcomes showed a median survival time of 6.0 months (95%CI: 5.9-6.2), an overall survival rate of 5.6% (95%CI: 1-24), and a 6-month survival rate of 46.5% (95%CI: 37.2-56.1). For nine studies (n=412) on SRS, the median survival was 7.9 months (95%CI: 5.1-10.8), and the 6-month survival rate was 63.1% (95%CI: 49.8-74.8). In six studies (n=75) using WBRT plus SRS, the median survival was 10.7 months (95%CI: 4.7-16.6), and the overall and 6-month survival rates were 16.8% (95%CI: 6.2-38.2) and 85.7% (95%CI: 28.3-96.9), respectively.

CONCLUSIONS

WBRT plus SRS showed better 1-year survival outcome than of WBRT alone for Korean patients with metastatic brain tumors. However, the results of this analysis have to be interpreted cautiously, because the risk factors of patients were not adjusted in the included studies.

Brain metastases of breast cancer

Brain metastases of breast cancer remain a difficult problem for clinical management. Their incidence appears to be increasing, which is likely due to longer survival times for advanced breast cancer patients as well as additional and improved tools for detection. Molecular features of tumors associated with this syndrome are not yet understood. In general, survival may be improving for brain metastases due to better local control in the CNS, as well as improvements in systemic disease management. Selected patients with brain metastases are able to undergo surgical resection, which has been associated with extended disease control in some patients. However, whole-brain radiation has been the mainstay for treatment for most patients. Stereotactic radiosurgery is playing an increasing role in the primary treatment of brain metastases, as well as for salvage after whole-brain radiation. Recent series have reported median survivals of 13 months or longer with stereotactic radiosurgery. Further improvements in radiation-based approaches may come from ongoing studies of radiosensitizing agents. The ability of systemic treatments to impact brain metastases has been debated, and specific treatment regimens have yet to be defined. New approaches include chemotherapy combinations, biologic therapies and novel drug-delivery strategies.

Stereotactic radiosurgery with and without whole-brain radiotherapy for newly diagnosed brain metastases

Brain metastases develop in 20-40% of cancer patients and can cause significant morbidity. In selected patients with one to three lesions, stereotactic radiosurgery may be used to improve local control. However, it is unclear whether whole-brain radiotherapy is necessary for all patients who are candidates for stereotactic radiosurgery. While whole-brain radiotherapy may improve the locoregional control of brain metastases, it may cause long-term side effects and may not improve overall survival in some patients. Its benefits should be evaluated in the context of risks of neurocognitive deterioration, either from whole-brain radiotherapy or from uncontrolled brain metastases, and the possible need for salvage treatments with the omission of initial whole-brain radiotherapy. For certain radioresistant brain metastases, the benefit of whole-brain radiotherapy to patients who have stereotactic radiosurgery is uncertain.

The role of whole-brain radiation therapy after stereotactic radiation surgery for brain metastases

The benefit of whole-brain radiation therapy (WBRT) following stereotactic radiation surgery (SRS) for brain metastases is controversial. We conducted a systematic analysis of published literature to explore the outcome of brain metastases treated with SRS and WBRT versus SRS alone using PubMed and MEDLINE. Outcomes including survival, control, salvage therapy, and other quality of life measures were reported. Three randomized controlled trials involving 389 patients with 1 to 4 brain metastases were selected. In 2 of these trials (n = 190), the mean 1-year survival was 33.2% for SRS + WBRT and 38.7% for SRS alone (P = .5233); 1-year local control was 89% for SRS + WBRT and 71% for SRS alone (P < .001). Mean crude distant recurrence rate for SRS + WBRT was 36.6% and 54% for SRS alone (P < .001). Patients without WBRT were over 3 times more likely to require salvage therapy (P < .001). The addition of WBRT was associated with a decreased health-related quality of life assessment, mini mental status exam, and Hopkins Verbal Learning Test (P < .05). Five retrospective studies (n = 1122) were also included in a separate analysis and yielded findings that supported results from the randomized trials. Our systematic analysis demonstrates that adjuvant WBRT following SRS for the treatment of oligometastases in the brain is more effective at controlling local and distant recurrence than SRS alone, but there is no apparent benefit for survival or symptomology. The proven cognitive decline and neurotoxicity present with WBRT should be weighed against the benefit of local control. Prognosis of brain metastasis is poor regardless of current treatment and further exploration for alternative adjuvant treatment for SRS is warranted.

Challenges relating to solid tumour brain metastases in clinical trials, part 1: patient population, response, and progression. A report from the RANO group

Therapeutic outcomes for patients with brain metastases need to improve. A critical review of trials specifically addressing brain metastases shows key issues that could prevent acceptance of results by regulatory agencies, including enrolment of heterogeneous groups of patients and varying definitions of clinical endpoints. Considerations specific to disease, modality, and treatment are not consistently addressed. Additionally, the schedule of CNS imaging and consequences of detection of new or progressive brain metastases in trials mainly exploring the extra-CNS activity of systemic drugs are highly variable. The Response Assessment in Neuro-Oncology (RANO) working group is an independent, international, collaborative effort to improve the design of trials in patients with brain tumours. In this two-part series, we review the state of clinical trials of brain metastases and suggest a consensus recommendation for the development of criteria for future clinical trials.

Clinical outcome in gamma knife radiosurgery for metastatic brain tumors from the primary breast cancer : prognostic factors in local treatment failure and survival

Objective

Brain metastases in primary breast cancer patients are considerable sources of morbidity and mortality. Gamma knife radiosurgery (GKRS) has gained popularity as an up-front therapy in treating such metastases over traditional radiation therapy due to better neurocognitive function preservation. The aim of this study was to clarify the prognostic factors for local tumor control and survival in radiosurgery for brain metastases from primary breast cancer.

Methods

From March 2001 to May 2011, 124 women with metastatic brain lesions originating from a primary breast cancer underwent GKRS at a tertiary medical center in Seoul, Korea. All patients had radiosurgery as a primary treatment or salvage therapy. We retrospectively reviewed their clinical outcomes and radiological responses. The end point of this study was the date of patient's death or the last follow-up examination.

Results

In total, 106 patients (268 lesions) were available for follow-up imaging. The median follow-up time was 7.5 months. The mean treated tumor volume at the time of GKRS was 6273 mm³ (range, 4.5-27745 mm³) and the median dose delivered to the tumor margin was 22 Gy (range, 20-25 Gy). Local recurrence was assessed in 86 patients (216 lesions) and found to have occurred in 36 patients (83 lesions, 38.6%) with a median time of 6 months (range, 4-16 months). A treated tumor volume >5000 mm³ was significantly correlated with poor local tumor control through a multivariate analysis (hazard risk=7.091, p=0.01). Overall survival was 79.9%, 48.3%, and 15.3% at 6, 12, and 24 months, respectively. The median overall survival was 11 months after GKRS (range, 6 days-113 months). Multivariate analysis showed that the pre-GKRS Karnofsky performance status, leptomeningeal seeding prior to initial GKRS, and multiple metastatic lesions were significant prognostic factors for reduced overall survival (hazard risk=1.94, p=0.001, hazard risk=7.13, p<0.001, and hazard risk=1.46, p=0.046, respectively).

Conclusion

GKRS has shown to be an effective and safe treatment modality for treating brain metastases of primary breast cancer. Most metastatic brain lesions initially respond to GKRS, though, many patients have further CNS progression in subsequent periods. Patients with poor Karnofsky performance status and multiple metastatic lesions are at risk of CNS progression and poor survival, and a more frequent and strict surveillance protocol is suggested in such high-risk groups.

The role of stereotactic radiosurgery for multiple brain metastases in stable systemic disease: a review of the literature

BACKGROUND

Cancer patients with brain metastases display a median survival of only 1 to 2 months if left untreated. Although whole-brain radiation therapy (WBRT) has lengthened median patient survival, the long-term neurotoxic effects of WBRT have become a deterrent to its use in the context of stable systemic disease. Therefore, it is important to identify patients who might benefit from stereotactic radiosurgery (SRS) in order to delay or avoid WBRT. Here we present a review of the literature to elucidate the role of SRS in patients with multiple brain metastases.

METHODS

MEDLINE search for English-language articles from 1998 to 2012 describing survival or neurocognitive functioning of patients with multiple brain metastases treated with SRS, WBRT, or a combination.

RESULTS

SRS monotherapy yields an equivalent survival with low risk of long-term neurotoxicity, but higher rate of recurrence, compared to WBRT or combined radiotherapy. Patients with ≤4 brain metastases or KPS ≥ 80 are expected to survive significantly longer than the onset time of prominent WBRT-induced neurocognitive decline.

CONCLUSIONS

SRS, administered alone or adjuvant to surgical resection of symptomatic metastases, is preferred for patients with ≤4 brain metastases or KPS ≥ 80 to delay or avoid WBRT. WBRT can then be employed in the event of recurrence. WBRT with or without resection is preferred for patients with ≥5 brain metastases and KPS < 80, due to these patients' shorter survival and increased recurrence risk. SRS boost treatments can then be used in the event of poor tumor response or progression.

Stereotactic radiosurgery in the treatment of brain metastases: the current evidence

Chemotherapy has made substantial progress in the therapy of systemic cancer, but the pharmacological efficacy is insufficient in the treatment of brain metastases. Fractionated whole brain radiotherapy (WBRT) has been a standard treatment of brain metastases, but provides limited local tumor control and often unsatisfactory clinical results. Stereotactic radiosurgery using Gamma Knife, Linac or Cyberknife has overcome several of these limitations, which has influenced recent treatment recommendations. This present review summarizes the current literature of single session radiosurgery concerning survival and quality of life, specific responses, tumor volumes and numbers, about potential treatment combinations and radioresistant metastases. Gamma Knife and Linac based radiosurgery provide consistent results with a reproducible local tumor control in both single and multiple brain metastases. Ideally minimum doses of ≥18Gy are applied. Reported local control rates were 90-94% for breast cancer metastases and 81-98% for brain metastases of lung cancer. Local tumor control rates after radiosurgery of otherwise radioresistant brain metastases were 73-90% for melanoma and 83-96% for renal cell cancer. Currently, there is a tendency to treat a larger number of brain metastases in a single radiosurgical session, since numerous studies document high local tumor control after radiosurgical treatment of >3 brain metastases. New remote brain metastases are reported in 33-42% after WBRT and in 39-52% after radiosurgery, but while WBRT is generally applied only once, radiosurgery can be used repeatedly for remote recurrences or new metastases after WBRT. Larger metastases (>8-10cc) should be removed surgically, but for smaller metastases Gamma Knife radiosurgery appears to be equally effective as surgical tumor resection (level I evidence). Radiosurgery avoids the impairments in cognition and quality of life that can be a consequence of WBRT (level I evidence). High local efficacy, preservation of cerebral functions, short hospitalization and the option to continue a systemic chemotherapy are factors in favor of a minimally invasive approach with stereotactic radiosurgery.

Preliminary results of linac-based radiosurgery in arteriovenous malformations and cerebral tumours in the Oncology Centre in Bydgoszcz

Aim of the study

Efficacy of stereotactic radiosurgery (SRS) in the treatment in cerebral AVM's, mennigiomas, metastases, acoustic neuromas and recurrent anaplastic gliomas is well documented. The object of this work was the analysis of the results of the treatment of AVM and selected cerebral lesions with linear accelerator-based stereotactic radiosurgery.

Material and methods

The lesions included: 12 AVMs, 2 cavernomas, 27 meningiomas, 16 metastases, 5 acoustic neuromas, 16 gliomas in 78 patients. A mean radiation dose of 16Gy was delivered to the tumour or AVM margin and 12Gy to the tumours located in a ponto-cerebellar angle. Follow-up was 18 months.

Results

Control of tumour growth or AVM was achieved in all cases after 6 months and radiological regression was observed in 20 cases after 12 months. The best results were noted in AVM's, meningiomas and neuromas.There were no new permanent deficits nor complications after radiosurgery requiring medicamentation.

Conclusions

Organization of SRS in Oncological Center in Bydgoszcz involving close co-operation of radiotherapist, neurosurgeon and physicist in the process of qualification and treatment planning is based on the best global standards. Preliminary results of treatment are consistent with the literature data. A longer follow-up is required to determine the long term efficacy and the toxicity of this treatment in our institution.

Population-based outcomes of boost versus salvage radiosurgery for brain metastases after whole brain radiotherapy

PURPOSE

We conducted a retrospective population-based study to examine the survival outcomes in patients with brain metastases treated with salvage stereotactic radiosurgery (SRS), compared to boost SRS, after previous whole brain radiotherapy (WBRT).

METHODS AND MATERIALS

From January 2000 to June 2011, 191 patients treated with WBRT and SRS for brain metastases in British Columbia were studied. Patients were divided into a boost cohort and a salvage cohort. The criteria used to determine eligibility for SRS were: 1-3 metastases, ≤4cm size, Karnofsky performance status ≥ 70, and control of extracranial disease.

RESULTS

Diagnosis by primary site was 84 lung, 47 breast, 15 melanoma, 12 renal, 9 colorectal, and 24 other. There were 113 patients (59%) in the boost cohort and 78 patients (41%) in the salvage cohort. The median overall survival from WBRT for the whole population was 17.7months: 12.1 months for the boost cohort and 22.7 months for the salvage cohort. There was no difference in median survival after SRS for the boost and salvage cohorts (11.2 vs. 11.2 months, p=0.78).

CONCLUSIONS

In selected patients with brain metastases treated with WBRT, survival following salvage SRS is as good as survival after WBRT + boost SRS.