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

Untoward global effects of current guideline formulation of stereotactic radiotherapy for symptomatic brain metastases by international medical societies

The quality of evidence leading to new oncological treatments suffers shortcomings, as has recently been addressed for drug approvals. In this 'Personal view', we evaluate the unintended effects of adopting stereotactic radiosurgery as the standard of care for patients with limited number of symptomatic brain metastases and favourable prognostic factors in international guidelines in view of the limitations in the evidence of efficacy and effectiveness, with special focus on countries with relatively limited resources.

Management of patients with brain metastases from NSCLC without a genetic driver alteration: upfront radiotherapy or immunotherapy?

Lung cancer is the second most common cancer and the most common cause of cancer-related death in the United States. Brain metastases (BM) are detected in 21% of patients with lung cancer at the time of diagnosis and are the sole metastatic site in 35% of patients with stage IV disease. The best upfront therapy for non-small-cell lung cancer depends on both tumor programmed death 1 ligand-1 (PD-L1) expression and the presence or absence of a targetable genetic alteration in genes such as epidermal growth factor receptor and anaplastic lymphoma kinase. In the absence of a targetable genetic alteration, options include chemotherapy, immune checkpoint inhibitors (ICIs), and ICI combined with chemotherapy. Upfront local therapy followed by systemic therapy is the current standard of care for the management of BM, and may include whole brain radiotherapy, stereotactic radiosurgery (SRS), or craniotomy for surgical resection followed by consolidative SRS. This paradigm is effective in achieving local control, but it remains unclear if this approach is necessary for every patient. Prospective and retrospective data suggest that ICIs with or without chemotherapy can have activity against BM; however, appropriately selecting patients who are able to safely forgo local therapy and start an ICI-based treatment remains a challenge. To be considered for upfront ICI-based therapy, a patient should be free of neurologic symptoms, lesions should be small and not located in a critical region of the central nervous system, if corticosteroids are indicated the requirement should be low (prednisone 10 mg/d or less), and PD-L1 expression should be high. The decision to proceed with upfront ICI without local therapy to BM should be made in a multidisciplinary fashion and patients should undergo frequent surveillance imaging so that salvage local therapy can be administered when necessary. Prospective clinical trials are needed to validate this approach before it can be widely adopted.

Comparison of initial and sequential salvage brain-directed treatment in patients with 1-4 vs. 5-10 brain metastases from breast cancer (KROG 16-12)

PURPOSE

We aimed to compare the initial and salvage brain-directed treatment and overall survival (OS) between patients with 1-4 brain metastases (BMs) and those with 5-10 from breast cancer (BC). We also organized a decision tree to select the initial whole-brain radiotherapy (WBRT) for these patients.

METHODS

Between 2008 and 2014, 471 patients were diagnosed with 1-10 BMs. They were divided into two groups based on the number of BM: 1-4 BMs (n = 337) and 5-10 BMs (n = 134). Median follow-up duration was 14.0 months.

RESULTS

Stereotactic radiosurgery (SRS)/fractionated stereotactic radiotherapy (FSRT) was the most common treatment modality (n = 120, 36%) in the 1-4 BMs group. In contrast, 80% (n = 107) of patients with 5-10 BMs were treated with WBRT. The median OS of the entire cohort, 1-4 BMs, and 5-10 BMs was 18.0, 20.9, and 13.9 months, respectively. In the multivariate analysis, the number of BM and WBRT were not associated with OS, whereas triple-negative BC and extracranial metastasis decreased OS. Physicians determined the initial WBRT based on four variables in the following order: number and location of BM, primary tumor control, and performance status. Salvage brain-directed treatment (n = 184), mainly SRS/FSRT (n = 109, 59%), prolonged OS by a median of 14.3 months.

CONCLUSION

The initial brain-directed treatment differed notably according to the number of BM, which was chosen based on four clinical factors. In patients with ≤ 10 BMs, the number of BM and WBRT did not affect OS. The major salvage brain-directed treatment modality was SRS/FSRT and increased OS.

The Value of Radiotherapy for Advanced Non-Small Cell Lung Cancer With Oncogene Driver-Mutation

Due to the widespread use of tyrosine kinase inhibitors (TKIs), which have largely supplanted cytotoxic chemotherapy as the first-line therapeutic choice for patients with advanced non-small cell lung cancer (NSCLC) who have oncogene driver mutations, advanced NSCLC patients with oncogene driver mutations had much long median survival. However, TKIs’ long-term efficacy is harmed by resistance to them. TKIs proved to have a limited potential to permeate cerebrospinal fluid (CSF) as well. Only a small percentage of plasma levels could be found in CSF at usual doses. Therefore, TKIs monotherapy may have a limited efficacy in individuals with brain metastases. Radiation has been demonstrated to reduce TKIs resistance and disrupt the blood-brain barrier (BBB). Previous trials have shown that local irradiation for bone metastases might improve symptoms, in addition, continuous administration of TKIs combined with radiotherapy was linked with beneficial progression-free survival (PFS) and overall survival (OS) for oligometastasis or bone metastasis NSCLC with oncogene driver mutations. The above implied that radiotherapy combined with targeted therapy may have a synergistic impact in patients with advanced oncogene driver-mutated NSCLC. The objective of this article is to discuss the value of radiotherapy in the treatment of those specific individuals.

Local recurrence and cerebral progression-free survival after multiple sessions of stereotactic radiotherapy of brain metastases: a retrospective study of 184 patients : Statistical analysis

PURPOSE

Forty to sixty percent of patients treated with focal therapy for brain metastasis (BM) will have distant brain recurrence (C-LR), while 10-25% of patients will have local recurrence (LR) within 1 year after stereotactic radiotherapy (SRT). The purpose of this study was to analyze cerebral progression-free survival (C-PFS) and LR of BM among patients treated with repeated courses of radiotherapy in stereotactic conditions.

METHODS AND MATERIALS

We retrospectively reviewed data from 184 patients treated for 915 BMs with at least two courses of SRT without previous WBRT. Initial patient characteristics, patient characteristics at each SRT, brain metastasis velocity (BMV), delay between SRT, MRI response, LR and C‑LR were analyzed.

RESULTS

In all, 123 (66.9%), 39 (21.2%), and 22 (12%) patients received 2, 3, or 4 or more SRT sessions, respectively. Ninety percent of BMs were irradiated without prior surgery, and 10% were irradiated after neurosurgery. The MRI response at 3, 6, 12 and 24 months after SRT was stable regardless of the SRT session. At 6, 12 and 24 months, the rates of local control were 96.3, 90.1, and 85.8%, respectively. In multivariate analysis, P‑LR was statistically associated with kidney (HR = 0.08) and lung cancer (HR = 0.3), ECOG 1 (HR = 0.5), and high BMV grade (HR = 5.6). The median C‑PFS after SRT1, SRT2, SRT3 and SRT4 and more were 6.6, 5.1, 6.7, and 7.7 months, respectively. C‑PFS after SRT2 was significantly longer among patients in good general condition (HR = 0.39), patients with high KPS (HR = 0.91), patients with no extracerebral progression (HR = 1.8), and patients with a low BMV grade (low vs. high: HR = 3.8).

CONCLUSION

Objective MRI response rate after repeated SRT is stable from session to session. Patients who survive longer, such as patients with breast cancer or with low BMV grade, are at risk of local reirradiation. C‑PFS after SRT2 is better in patients in good general condition, without extracerebral progression and with low BMV grade.

Radiosurgery for brain oligometastases in lung cancer

INTRODUCTION Brain metastases are a common problem in oncology patients, especially in lung cancer. The usual treatment for cerebral oligometastases is whole brain radiation therapy. Given the persistent poor prognosis of this disease, other therapeutic alternatives such as stereotactic radiosurgery have been considered. However, there is no clarity regarding the effectiveness of its addition. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified 17 systematic reviews including seven studies overall, of which four were randomized trials. All trials assessed patients with brain oligometastases, but none of them included exclusively lung cancer population. We concluded that it is not possible to clearly establish whether radiosurgery decreases neurological functionality, cognitive impairment, mortality or serious adverse effects, as the certainty of the existing evidence has been assessed as very low.

The microenvironment of brain metastases from solid tumors

Brain metastasis (BrM) is an area of unmet medical need that poses unique therapeutic challenges and heralds a dismal prognosis. The intracranial tumor microenvironment (TME) presents several challenges, including the therapy-resistant blood-brain barrier, a unique immune milieu, distinct intercellular interactions, and specific metabolic conditions, that are responsible for treatment failures and poor clinical outcomes. There is a complex interplay between malignant cells that metastasize to the central nervous system (CNS) and the native TME. Cancer cells take advantage of vascular, neuronal, immune, and anatomical vulnerabilities to proliferate with mechanisms specific to the CNS. In this review, we discuss unique aspects of the TME in the context of brain metastases and pathways through which the TME may hold the key to the discovery of new and effective therapies for patients with BrM.

Anti-PD1 Therapy Plus Whole-Brain Radiation Therapy May Prolong PFS in Selected Non-Small Cell Lung Cancer Patients with Brain Metastases: A Retrospective Study

Background

Whole-brain radiotherapy (WBRT) remains an essential modality of treatment for brain metastases (BMs) derived from non-small cell lung cancer (NSCLC) patients and anti-PD-1 therapy has demonstrated intracranial responses in these patients. We aimed to evaluate if the combination of the two treatments could yield additive efficacy.

Methods

A retrospective review of our institution’s database was carried out to identify NSCLC patients with BMs who had been treated with anti-PD1 therapy and/or WBRT between 2015 and 2020. Patient characteristics, main outcomes, including progression-free survival (PFS) and overall survival (OS), and factors affecting these outcomes were analyzed. SPSS 24 was used for statistical analysis. Appropriate statistical tests were employed according to the type of data.

Results

Overall, 21 NSCLC BM patients were identified that had received WBRT. Of these, ten had been additionally treated with anti-PD1 therapy within 30 days of WBRT initiation. Median PFS was 3 (95% CI 0.8–5.1) months with WBRT alone versus 11 (95% CI 6.3–15.6) months with combined treatment. Risk of disease progression was 71% lower with the combined approach (HR 0.29, 95% CI 0.11–0.80; p=0.016). A trend toward improved OS was also observed with the combined approach (HR 0.33, 95% CI 0.08–1.12; p=0.107). Concurrent treatment (p=0.028) and male sex (p=0.052) were associated with improved PFS, while OS was associated only with age (p=0.02).

Conclusion

Concurrent WBRT and anti-PD1 therapy may delay progression and improve survival in BM patients with confirmed EGFR- and ALK-negative NSCLC histology. Prospective studies are warranted to validate and elucidate on the additive effect of the two modalities.

Laser interstitial thermal therapy for brain metastases

Laser interstitial thermal therapy (LITT) is a minimally invasive treatment for intracranial lesions entailing thermal ablation via a stereotactically placed laser probe. In metastatic disease, it has shown the most promise in the treatment of radiographically progressive lesions after initial stereotactic radiosurgery, whether due to recurrent metastatic disease or radiation necrosis. LITT has been demonstrated to provide clinical benefit in both cases, as discussed in the review below. With its minimal surgical footprint and short recovery period, LITT is further advantaged for patients who are otherwise high-risk surgical candidates or with lesions in difficult to access locations. Exploration of the current data on its use in metastatic disease will allow for a better understanding of the indications, benefits, and future directions of LITT for these patients.

Radiation Plus Anti-PD-1 Therapy for NSCLC Brain Metastases: A Retrospective Study

Background

Radiation therapy (RT) is the mainstay of brain metastases (BMs), and anti-PD-1 blockade has led to intracranial responses in non-small cell lung carcinoma (NSCLC) patients with BMs.

Objective

This study aimed to evaluate the efficacy and safety of adding anti-PD-1 blockade to RT in the management of NSCLC patients with BM in terms of survival outcome.

Materials and Methods

We retrospectively reviewed 70 NSCLC patients with BMs who were treated with whole brain radiation therapy (WBRT) between January 2016 and January 2021. Of the 70 patients, 29 additionally received anti-PD-1 therapy within 30 days of WBRT initiation. Baseline characteristics of the patients and efficacy outcomes such as progression-free survival (PFS) and overall survival (OS) were statistically compared using SPSS v26. Results were obtained using the Chi-square test/Fisher exact test, t-test, Kaplan-Meier, and Cox regression survival analyses.

Results

The median survival for the entire cohort was 24 months (95% CI, 19.5–28.5). The median survival times for WBRT alone and WBRT plus anti-PD-1 therapy cohorts were 20 months (95% CI, 11.6–28.3) and 27 months (95% CI, 19.5–28.5), respectively (p=0.035). There was no statistical difference in PFS for the treatment cohorts (median PFS for WBRT alone: 7 months vs. 12 months for WBRT plus anti-PD-1, p=0.247). In EGFR wild-type subgroup (n=31), both PFS (p=0.037) and OS (p=0.012) were significantly improved. Only the treatment group (WBRT plus anti-PD-1) was a significant predictor of OS on univariate and multivariate analyses (p=0.040). There were no significant differences in adverse events among the treatment groups.

Conclusions

NSCLC patients with BM receiving additional anti-PD-1 therapy may derive better OS than WBRT alone without any increase in adverse events. Prospective well-designed studies are warranted to validate and elucidate the additive effects of the two modalities in this group of patients.

Brain metastases in patients with oncogenic-driven non-small cell lung cancer: Pros and cons for early radiotherapy

Non-small cell lung cancer (NSCLC) with oncogenic driver mutations such as EGFR or ALK has a high predilection for brain metastases (BMs) compared to unselected patients. Historically, whole brain radiotherapy (WBRT) was adopted widely for patients with BM. More recently, stereotactic radiosurgery (SRS) has become a standard approach for patients with 1 - 4 metastatic brain lesions. However, data on overall survival benefit with WBRT/SRS compared to target agents are conflicting, with a significant compromise of loss of neurocognitive function. Newer target agents with improved CNS efficacy have challenged the use of early radiotherapy in NSCLC patients with oncogenic driver mutations. Optimal treatment approach and timing of radiotherapy remain unclear, especially under the various clinical contexts. The purpose of this review is to summarize the available data on the possible benefits and risks of early radiotherapy for oncogenic-driven NSCLC patients with brain metastases. Clinical decisions should consider both intracranial efficacy and patient quality of life, given that patients are surviving long enough to experience the long-term consequences of radiation therapy.

Survival After Stereotactic Radiosurgery (SRS) or Fractionated Stereotactic Radiotherapy (FSRT) for Cerebral Metastases in the Elderly

BACKGROUND/AIM

Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) have gained popularity especially for treating 1-3 cerebral metastases. Elderly patients benefit from treatment personalisation. A specific survival score was created to facilitate this approach.

PATIENTS AND METHODS

Ten characteristics were retrospectively analysed for survival in 104 elderly patients with 1-3 cerebral metastases receiving SRS or FSRT alone using a linear accelerator or Cyberknife®.

RESULTS

On multivariate analysis, better survival was significantly associated with KPS of 90-100 (p=0.049), single lesion (p=0.036), maximum cumulative diameter of all lesions <16 mm (p=0.026) and supratentorial involvement only (p=0.047). Three groups were formed with 12-14 points (n=22), 15-16 points (n=33) and 17-19 points (n=49) with 12-month survival rates of 7%, 34% and 58% (p<0.0001), respectively. Positive predictive values for predicting death ≤12 months and survival ≥12 months were 95% and 54%.

CONCLUSION

The new score showed very high accuracy in predicting death ≤12 months, but not in predicting survival ≥12 months.

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.

Bevacizumab Treatment of Radiation-Induced Brain Necrosis: A Systematic Review

Background

Radiation brain necrosis (RBN) is a serious complication in patients receiving radiotherapy for intracranial disease. Many studies have investigated the efficacy and safety of bevacizumab in patients with RBN. In the present study, we systematically reviewed the medical literature for studies reporting the efficacy and safety of bevacizumab, as well as for studies comparing bevacizumab with corticosteroids.

Materials and Methods

We searched PubMed, Cochrane library, EMBASE, and ClinicalTrials.gov from their inception through 1 March, 2020 for studies that evaluated the efficacy and safety of bevacizumab in patients with RBN. Two investigators independently performed the study selection, data extraction, and data synthesis.

Results

Overall, the present systematic review included 12 studies (eight retrospective, two prospective, and two randomized control trials [RCTs]) involving 236 patients with RBN treated who were treated with bevacizumab. The two RCTs also had control arms comprising patients with RBN who were treated with corticosteroids/placebo (n=57). Radiographic responses were recorded in 84.7% (200/236) of patients, and radiographic progression was observed in 15.3% (36/236). Clinical improvement was observed in 91% (n=127) of responding patients among seven studies (n=113). All 12 studies reported volume reduction on T1 gadolinium enhancement MRI (median: 50%, range: 26%–80%) and/or T2 FLAIR MRI images (median: 59%, range: 48%–74%). In total, 46 responding patients (34%) had recurrence. The two RCTs revealed significantly improved radiographic response in patients treated with bevacizumab (Levin et al.: p = 0.0013; Xu et al.: p < 0.001). Both also showed clinical improvement (Levin et al.: NA; Xu et al.: p = 0.039) and significant reduction in edema volume on both T1 gadolinium enhancement MRI (Levin et al.: p=0.0058; Xu et al.: p=0.027) and T2 FLAIR MRI (Levin et al.: p=0.0149; Xu et al.: p < 0.001). Neurocognitive improvement was significantly better after 2 months of treatment in patients receiving bevacizumab than in those given corticosteroids, as assessed by the MoCA scale (p = 0.028). The recurrence rate and side effects of the treatments showed no significant differences.

Conclusions

Patients with RBN respond to bevacizumab, which can improve clinical outcomes and cognitive function. Bevacizumab appears to be more efficacious than corticosteroid-based treatment. The safety profile was comparable to that of the corticosteroids.

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

Background

Radiotherapy is the mainstay of brain metastasis (BM) management. Radiation necrosis (RN) is a serious complication of radiotherapy. Bevacizumab (BV), an anti-vascular endothelial growth factor monoclonal antibody, has been increasingly used for RN treatment. We systematically reviewed the medical literature for studies reporting the efficacy and safety of bevacizumab for treatment of RN in BM patients.

Materials and methods

PubMed, Medline, EMBASE, and Cochrane library were searched with various search keywords such as “bevacizumab” OR “anti-VEGF monoclonal antibody” AND “radiation necrosis” OR “radiation-induced brain necrosis” OR “RN” OR “RBN” AND “Brain metastases” OR “BM” until 1st Aug 2020. Studies reporting the efficacy and safety of BV treatment for BM patients with RN were retrieved. Study selection and data extraction were carried out by independent investigators. Open Meta Analyst software was used as a random effects model for meta-analysis to obtain mean reduction rates.

Results

Two prospective, seven retrospective, and three case report studies involving 89 patients with RN treated with BV were included in this systematic review and meta-analysis. In total, 83 (93%) patients had a recorded radiographic response to BV therapy, and six (6.7%) had experienced progressive disease. Seven studies (n = 73) reported mean volume reductions on gadolinium-enhanced T1 (mean: 47.03%, +/− 24.4) and T2-weighted fluid-attenuated inversion recovery (FLAIR) MRI images (mean: 61.9%, +/− 23.3). Pooling together the T1 and T2 MRI reduction rates by random effects model revealed a mean of 48.58 (95% CI: 38.32–58.85) for T1 reduction rate and 62.017 (95% CI: 52.235–71.799) for T2W imaging studies. Eighty-five patients presented with neurological symptoms. After BV treatment, nine (10%) had stable symptoms, 39 (48%) had improved, and 34 (40%) patients had complete resolution of their symptoms. Individual patient data was available for 54 patients. Dexamethasone discontinuation or reduction in dosage was observed in 30 (97%) of 31 patients who had recorded dosage before and after BV treatment. Side effects were mild.

Conclusions

Bevacizumab presents a promising treatment strategy for patients with RN and brain metastatic disease. Radiographic response and clinical improvement was observed without any serious adverse events. Further class I evidence would be required to establish a bevacizumab recommendation in this group of patients.

Benefit of dosimetry distribution for patients with multiple brain metastases from non-small cell lung cancer by a Cyberknife stereotactic radiosurgery (SRS) system

BACKGROUND

In order to obtain a high dose conformal index of tumor and steep dose fall-off in healthy tissues for brain metastasis stereotactic radiosurgery (SRS), the aim of this study was to investigate SRS planning optimization by comparing one multiple-lesions plan (MLP) with multiple single-lesion plans (SLPs) for patients with multiple brain metastases using the Cyberknife (CK) system.

METHODS

Fifty non-small cell lung cancer (NSCLC) patients (28 males and 22 females) with 2-4 brain metastases, inter-tumour distances less than 3 cm, were retrospectively replanned with the original prescription dose (12-32 Gy) in the original fractions (1-3). Two different clinical CK SRS plans (SLPs and MLP) were generated for the same patients with the same collimator and prescription isodose line (62-68%) by the CK Multiplan System. Both SLPs and MLP were able to achieve > 95% PTV volume covered prescription dose and met the Timmerman 2011 organs at risk (brainstem, optic nerve and pituitary) constraints.

RESULTS

Compared with those in the SLPs, the maximum dose (D_max) and mean dose (D_mean) of brainstem in the MLP were reduced 0.22-3.13% (2.62%) and 2.71-12.56% (5.57%), respectively, all P < 0.05. Meanwhile, the volumes of the whole brain minus the tumors that received a single dose equivalent of 8-16 Gy (V8Gy-V16Gy) were effectively reduced in the MLP. The treatment time parameters, the total number of beams and monitor units, of the MLP were reduced by 3.31 and 1.47% (P < 0.05), respectively. Although there were a few differences in the conformity index (CI) and homogeneity index (HI) between the two treatment plans, the differences were not statistically significant (P = 2.94 and 1.08 > 0.05).

CONCLUSION

One multiple-lesions plan for brain metastases could achieve higher precision in the target and lower doses in healthy tissue while shortening the treatment time and improving the treatment efficiency over multiple single-lesion plans.

Pre-Treatment Seizures in Patients With 1-3 Cerebral Metastases Receiving Local Therapies Plus Whole-brain Radiotherapy

BACKGROUND/AIM

Seizures impair patients' quality of life. The prognostic role of pre-treatment seizures in patients with 1-3 cerebral metastases receiving local therapies plus whole-brain radiotherapy (WBRT) was investigated.

PATIENTS AND METHODS

In 249 patients, prevalence, risk factors and associations of pre-treatment seizures with survival were retrospectively evaluated. Age, gender, performance score, tumor type, number of lesions, extra-cerebral metastases, and time from tumor diagnosis to treatment of cerebral metastasis were analyzed for associations with seizures. These characteristics and pre-treatment seizures were also analyzed for associations with survival.

RESULTS

The prevalence of pre-treatment seizures was 24.1%. Trends for associations were found between seizures and gender or performance score. On multivariate analysis, age (p=0.008), performance score (p=0.004), tumor type (p<0.001) and extra-cerebral metastasis (p<0.001) were significantly associated with survival.

CONCLUSION

Seizures were comparably common prior to local therapies plus WBRT for cerebral metastases. No factor was found to be significantly associated with seizures, and seizures were not associated with survival.

Tumor Primary Site and Histology Subtypes Role in Radiotherapeutic Management of Brain Metastases

Randomized controlled trials have failed to report any survival advantage for WBRT combined with SRS in the management of brain metastases, despite the enhanced local and distant control in comparison to each treatment alone. Literature review have revealed important role of primary histology of the tumor when dealing with brain metastases. NSCLC responds better to combined approach even when there was only single brain metastasis present while breast cancer has registered better survival with SRS alone probably due to better response of primary tumor to advancement in surgical and chemotherapeutic agents. Furthermore, mutation status (EGFR/ALK) in lung cancer and receptor status (ER/PR/HER2) in breast cancer also exhibit diversity in their response to radiotherapy. Radioresistant tumors like renal cell carcinoma and melanoma brain metastases have achieved better results when treated with SRS alone. Secondly, single brain metastasis may benefit from local and distant brain control achieved with combined treatment. These diverse outcomes suggest a primary histology-based analysis of the radiotherapy regimens (WBRT, SRS, or their combination) would more ideally establish the role of radiotherapy in the management of brain metastases. Molecularly targeted therapeutic and immunotherapeutic agents have revealed synergism with radiation therapy particularly SRS in treating cancer patients with brain metastases. Clinical updates in this regard have also been reviewed.

Validation of recursive partitioning analysis, graded prognostic assessment and basic score for brain metastases as prognostic indices among patients with brain metastases treated with radiotherapy in Indonesia

Introduction:

Metastatic brain disease is still a major contributor to cancer treatment failure. Various treatments have improved in the recent decades, which allow for better control of brain metastatic lesions. Various prognostic scoring tools have been developed and used worldwide to stratify patients with brain metastases to determine who will benefit most from aggressive treatment. The three most commonly used prognostic scoring tools are recursive partitioning analysis (RPA), basic score for brain metastases (BSBM) and graded prognostic assessment (GPA). The aim of this study is to validate these scoring tools using an Indonesian cancer patient population.

Method:

A retrospective analysis of all patients presenting with brain metastases from January 2012 until December 2014, through using hospital medical records, was conducted. All patients receiving whole brain radiotherapy during this period were included in this study. A follow-up with a telephone call was carried out to determine the patient’s health and survival status. Uncontactable patients were excluded from the analysis. Survival analysis was carried out by stratifying patients based on the three prognostic scoring systems.

Result:

A total of 80 patients were eligible to be included in the study, with 18 excluded due to being uncontactable. The remaining 62 patients’ data were analysed and stratified with all three scoring systems. The RPA was found to confer better stratification than BSBM and GPA in our study population.

Conclusion:

GPA was non-prognostic in our study population and BSBM was less prognostic, especially in the middle group, class 1 and class 2. Those BSBM class 1 and class 2 did not provide good prognostic stratification in our study population, whereas RPA was proven to be the best in stratifying patients’ prognosis with brain metastases in our study population.

Significant reduction of oncologic pulmonary death by local control for pulmonary oligometastases treated with stereotactic body radiotherapy

BACKGROUND AND PURPOSE

The rate of oncologic pulmonary death after stereotactic body radiotherapy for pulmonary oligometastases has never been reported. The purpose of current study was to investigate the rate of freedom from oncologic pulmonary death (FOPD) and to analyze factors affecting for FOPD.

MATERIALS AND METHODS

The inclusion criteria for this retrospective study were that SBRT was performed between 2004 and 2015, the number of metastases was 5 or less, the primary lesion and extrathoracic metastases needed to be controlled before SBRT and a biological effective dose (BED₁₀) of 75 Gy or more was needed. The Kaplan-Meier estimator and the log-rank test were used to calculate and compare the stratified rates of FOPD. The Cox proportional hazards model was used for multivariate analyses (MVA). Primary disease death from a non-oncologic pulmonary cause was censored in model 1 and was excluded in model 2.

RESULTS

A total of 1172 patients with 1315 tumors were enrolled. During a median follow-up period of 24.5 months, oncologic pulmonary deaths accounted for 101 of 221 primary disease deaths. The 1-year, 3-year and 5-year FOPD rates in model 1 were 98.2%, 89.4% and 84.0%, respectively. MVA for FOPD revealed that local failure of the irradiated tumor, squamous cell carcinoma pathology, and chemotherapy after SBRT had significant relationships with lower FOPD rates in both model 1 and model 2.

CONCLUSIONS

Successful local control of pulmonary oligometastases by SBRT contributed to a higher FOPD rate.

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.

Turning "Cold" Into "Hot" Tumors-Opportunities and Challenges for Radio-Immunotherapy Against Primary and Metastatic Brain Cancers

The development of immunotherapies has revolutionized intervention strategies for a variety of primary cancers. Despite this promising progress, treatment options for primary brain cancer and brain metastasis remain limited and still largely depend on surgical resection, radio- and/or chemotherapy. The paucity in the successful development of immunotherapies for brain cancers can in part be attributed to the traditional view of the brain as an immunologically privileged site. The presence of the blood-brain barrier and the absence of lymphatic drainage were believed to restrict the entry of blood-borne immune and inflammatory cells into the central nervous system (CNS), leading to an exclusion of the brain from systemic immune surveillance. However, recent insight from pre-clinical and clinical studies on the immune landscape of brain cancers challenged this dogma. Recruitment of blood-borne immune cells into the CNS provides unprecedented opportunities for the development of tumor microenvironment (TME)-targeted or immunotherapies against primary and metastatic cancers. Moreover, it is increasingly recognized that in addition to genotoxic effects, ionizing radiation represents a critical modulator of tumor-associated inflammation and synergizes with immunotherapies in adjuvant settings. This review summarizes current knowledge on the cellular and molecular identity of tumor-associated immune cells in primary and metastatic brain cancers and discusses underlying mechanisms by which ionizing radiation modulates the immune response. Detailed mechanistic insight into the effects of radiation on the unique immune landscape of brain cancers is essential for the development of multimodality intervention strategies in which immune-modulatory effects of radiotherapy are exploited to sensitize brain cancers to immunotherapies by converting immunologically “cold” into “hot” environments.

VCAM-1-targeted MRI Enables Detection of Brain Micrometastases from Different Primary Tumors

PURPOSE

A major issue for the effective treatment of brain metastasis is the late stage of diagnosis with existing clinical tools. The aim of this study was to evaluate the potential of vascular cell adhesion molecule 1 (VCAM-1)-targeted MRI for early detection of brain micrometastases in mouse models across multiple primary tumor types.Experimental Design: Xenograft models of brain micrometastasis for human breast carcinoma (MDA231Br-GFP), lung adenocarcinoma (SEBTA-001), and melanoma (H1_DL2) were established via intracardiac injection in mice. Animals (n = 5-6/group) were injected intravenously with VCAM-1-targeted microparticles of iron oxide (VCAM-MPIO) and, subsequently, underwent T 2*-weighted MRI. Control groups of naïve mice injected with VCAM-MPIO and tumor-bearing mice injected with nontargeting IgG-MPIO were included.

RESULTS

All models showed disseminated micrometastases in the brain, together with endothelial VCAM-1 upregulation across the time course. T 2*-weighted MRI of all tumor-bearing mice injected with VCAM-MPIO showed significantly more signal hypointensities (P < 0.001; two-sided) than control cohorts, despite a lack of blood-brain barrier (BBB) impairment. Specific MPIO binding to VCAM-1-positive tumor-associated vessels was confirmed histologically. VCAM-1 expression was demonstrated in human brain metastasis samples, across all three primary tumor types.

CONCLUSIONS

VCAM-1-targeted MRI enables the detection of brain micrometastases from the three primary tumor types known to cause the majority of clinical cases. These findings represent an important step forward in the development of a broadly applicable and clinically relevant imaging technique for early diagnosis of brain metastasis, with significant implications for improved patient survival.

Stereotactic radiosurgery (SRS) alone versus whole brain radiotherapy plus SRS in patients with 1 to 4 brain metastases from non-small cell lung cancer stratified by the graded prognostic assessment: A meta-analysis (PRISMA) of randomized control trials

BACKGROUND

The present study aims to assess the therapeutic effect of whole brain radiotherapy (WBRT) for brain metastases from non-small cell lung cancer stratified by graded prognostic assessment (GPA) through meta-analysis.

METHODS

The Cochrane Library, PubMed, Ovid (Elsevier) were retrieved. The included randomized controlled trials (RCT) were evaluated, and the statistical analysis was performed using RevMan 5.3 software. Cochrane handbook was applied to evaluate the methodological quality. Statistical significance was considered as P < .05.

RESULTS

There were 2 randomized control trials identified eligible for the meta-analysis. Stereotactic radiosurgery (SRS)+WBRT did not significantly improved overall survival (OS) in 2 subgroups. (GPA <2: HR, 0.93; 95% confidence interval [CI], 0.61-1.40; P = .71), (GPA ≥2: HR, 1.28; 95% CI, 0.58-2.80; P = .54). The use of SRS+WBRT significantly extended brain tumor recurrence (BTR) free time in both subgroups (GPA <2: HR, 5.46; 95% CI: 2.09-14.22; P = .0005), (GPA ≥2: HR, 4.24; 95% CI: 2.24-8.04; P < .00001). The meta-analysis showed salvage therapy was more frequent among the SRS-alone in 2 subgroups (GPA <2: RR, 5.83; 95% CI: 1.47-23.06; P = .01), (GPA ≥2: RR, 2.53; 95% CI: 1.30-4.93; P = .006). The rate of grade 3 or 4 late radiation toxic effects was similar in 2 subgroups between SRS and SRS+WBRT CONCLUSIONS:: Because there are few studies to meet inclusion criteria, we cannot include more researches. The results of this analysis must be carefully interpreted in view of the unclear risk of bias in inclusion in the study. This meta-analysis of 2 randomized trails indicated that the combined treatment group did not show a survival benefit over SRS alone. However, SRS+WBRT improved BTR free time in the subgroup both GPA <2 and GPA ≥2 with the similar grade 3 or 4 late radiation toxicities.

Survival after whole brain radiotherapy for brain metastases from lung cancer and breast cancer is poor in 6325 Dutch patients treated between 2000 and 2014

BACKGROUND

Whole brain radiotherapy (WBRT) is considered standard of care for patients with multiple brain metastases or unfit for radical treatment modalities. Recent studies raised discussion about the expected survival after WBRT. Therefore, we analysed survival after WBRT for brain metastases 'in daily practice' in a large nationwide multicentre retrospective cohort.

METHODS

Between 2000 and 2014, 6325 patients had WBRT (20 Gy in 4 Gy fractions) for brain metastases from non-small cell lung cancer (NSCLC; 4363 patients) or breast cancer (BC; 1962 patients); patients were treated in 15 out of 21 Dutch radiotherapy centres. Survival was calculated by the Kaplan-Meier method from the first day of WBRT until death as recorded in local hospital data registration or the Dutch Municipal Personal Records Database.

FINDINGS

The median survival was 2.7 months for NSCLC and 3.7 months for BC patients (p < .001). For NSCLC patients aged <50, 50-60, 60-70 and >70 years, survival was 4.0, 3.0, 2.8 and 2.1 months, respectively (p < .001). For BC patients, survival was 4.5, 3.8, 3.2 and 2.9 months, respectively (p = .047). In multivariable analyses, higher age was related to poorer survival with hazard ratios (HR) for patients aged 50-60, 60-70 and >70 years being 1.05, 1.19 and 1.34, respectively. Primary BC (HR: 0.83) and female sex (HR: 0.85) were related to better survival (p < .001).

INTERPRETATION

The survival of patients after WBRT for brain metastases from NSCLC treated in Dutch 'common radiotherapy practice' is poor, in breast cancer and younger patients it is disappointingly little better. These results are in line with the results presented in the QUARTZ trial and we advocate a much more restrictive use of WBRT. In patients with a more favourable prognosis the optimal treatment strategy remains to be determined. Prospective randomized trials and individualized prognostic models are needed to identify these patients and to tailor treatment.