Response assessment criteria for brain metastases: proposal from the RANO group

Consensus recommendations on standardized magnetic resonance imaging protocols for multicenter canine brain tumor clinical trials

The National Cancer Institute Comparative Brain Tumor Consortium, Patient Outcomes Working Group, propose a consensus document in support of standardized magnetic resonance imaging protocols for canine brain tumor clinical trials. The intent of this manuscript is to address the widely acknowledged need to ensure canine brain tumor imaging protocols are relevant and have sufficient equivalency to translate to human studies such that: (1) multi-institutional studies can be performed with minimal inter-institutional variation, and (2) imaging protocols are consistent with human consensus recommendations to permit reliable translation of imaging data to human clinical trials. Consensus recommendations include pre- and postcontrast three-dimensional T1-weighted images, T2-weighted turbo spin echo in all three planes, T2*-weighted gradient recalled echo, T2-weighted fluid attenuated inversion recovery, and diffusion weighted imaging/diffusion tensor imaging in transverse plane; field of view of ≤150 mm; slice thickness of ≤2 mm, matrix ≥ 256 for two-dimensional images, and 150 or 256 for three-dimensional images.

Evaluation of Stereotactic Radiotherapy of the Resection Cavity After Surgery of Brain Metastases Compared to Postoperative Whole-Brain Radiotherapy (ESTRON)—A Single-Center Prospective Randomized Trial

BACKGROUND

Neurosurgical resection is recommended for symptomatic brain metastases, in oligometastatic patients or for histology acquisition. Without adjuvant radiotherapy, roughly two-thirds of the patients relapse at the resection site within 24 mo, while the risk of new metastases in the untreated brain is around 50%. Adjuvant whole-brain radiotherapy (WBRT) can reduce the risk of both scenarios of recurrence significantly, although the associated neurocognitive toxicity is substantial, while stereotactic radiotherapy (SRT) improves local control at comparably low toxicity.

OBJECTIVE

To compare locoregional control and treatment-associated toxicity for postoperative SRT and WBRT after the resection of 1 brain metastasis in a single-center prospective randomized study.

METHODS

Fifty patients will be randomized to receive either hypofractionated SRT of the resection cavity and single- or multisession SRT of all unresected brain metastases (up to 10 lesions) or WBRT. Patients will be followed-up regularly and the primary endpoint of neurological progression-free survival will be assessed by magnetic resonance imaging (MRI). Quality of life and neurocognition will be assessed in 3-mo intervals using standardized tests and EORTC questionnaires.

EXPECTED OUTCOMES

We expect to show that postoperative SRT of the resection cavity and further unresected brain metastases is a valid means of improving locoregional control over observation at less neurocognitive toxicity than caused by WBRT.

DISCUSSION

The present study is the first to compare locoregional control as well as neurocognitive toxicity for postoperative SRT and WBRT in patients with up to 10 metastases, while utilizing a highly sensitive and standardized MRI protocol for treatment planning and follow-up.

Outcomes of stereotactic radiosurgery of brain metastases from neuroendocrine tumors

Background

Stereotactic radiosurgery (SRS) is an established treatment for brain metastases, yet little is known about SRS for neuroendocrine tumors given their unique natural history.

Objective

To determine outcomes and toxicity from SRS in patients with brain metastases arising from neuroendocrine tumors.

Methods

Thirty-three patients with brain metastases from neuroendocrine tumors who underwent SRS were retrospectively reviewed. Median age was 61 years and median Karnofsky performance status was 80. Primary sites were lung (87.9%), cervix (6.1%), esophagus (3%), and prostate (3%). Ten patients (30.3%) received upfront SRS, 7 of whom had neuroendocrine tumors other than small cell lung carcinoma. Kaplan-Meier survival and Cox regression analyses were performed to determine prognostic factors for survival.

Results

With median follow-up after SRS of 5.3 months, local and distant brain recurrence developed in 5 patients (16.7%) and 20 patients (66.7%), respectively. Median overall survival (OS) after SRS was 6.9 months. Patients with progressive disease per Response Assessment in Neuro-Oncology-Brain Metastases (RANO-BM) criteria at 4 to 6 weeks after SRS had shorter median time to developing recurrence at a distant site in the brain and shorter OS than patients without progressive disease: 1.4 months and 3.3 months vs 11.4 months and 12 months, respectively (both P < .001). Toxicity was more likely in lesions of small cell histology than in lesions of other neuroendocrine tumor histology, 15.7% vs 3.3% (P = .021). No cases of grade 3 to 5 necrosis occurred.

Conclusions

SRS is an effective treatment option for patients with brain metastases from neuroendocrine tumors with excellent local control despite slightly higher toxicity rates than expected. Progressive disease at 4 to 6 weeks after SRS portends a poor prognosis.

Targeted Therapy and Immunotherapy Response Assessment with F-18 Fluorothymidine Positron-Emission Tomography/Magnetic Resonance Imaging in Melanoma Brain Metastasis: A Pilot Study

INTRODUCTION

This pilot study aimed at exploring the utility of the proliferation tracer F-18 fluorothymidine (FLT) and positron-emission tomography (PET)/magnetic resonance imaging (MRI) (FLT-PET/MRI) for early treatment monitoring in patients with melanoma brain metastasis (MBM) who undergo targeted therapy or immunotherapy.

MATERIAL AND METHODS

Patients with newly diagnosed MBM underwent baseline and follow-up FLT-PET/MRI scans at 3-4 weeks of targeted therapy or immunotherapy. Up to six measurable brain lesions ≥1.0 cm per subject, as identified on T1-weighted post-gadolinium images, were included for quantitative analyses. The maximum SUV of each lesion was divided by the mean SUV of the pons to obtain the SUV ratio (SUVR).

RESULTS

Five enrolled subjects underwent the baseline FLT-PET/MRI study in which the MBM showed a median size of 1.7 cm (range 1.0-2.9) and increased metabolic activity with SUVR of 9.9 (range 3.2-18.4). However, only two subjects (cases #1 and #2) returned for a follow-up scan. At baseline, a total of 22 lesions were analyzed in all five subjects, which showed a median size of 1.7 cm (range 1.0-2.9) and median SUVR of 9.9 (range 3.2-18.4). At follow-up, case #1 was a 55-year-old man who received targeted BRAF inhibitor and MEK inhibitor therapy with dabrafenib and trametinib. Fused PET/MRI data of six measured lesions demonstrated a significant reduction in MBM proliferative activity (median -68%; range -38 to -77%) and size (median -23%; range -4 to -55%) at three weeks of therapy. Nevertheless, the subject eventually progressed and died 13 months after therapy initiation. Case #2 was a 36-year-old man who received immunotherapy with nivolumab and ipilimumab. The five measured MBM lesions showed a mixed response at both proliferative and morphologic imaging at 1-month follow-up. Some lesions demonstrated interval decrease while others interval increase in proliferative activity with a median -44% (range -77 to +68%). On MRI, the size change was +7% (range -64 to +50%). The therapy was switched to dabrafenib and trametinib, which led to a partial response. The patient is still alive 16 months following therapy initiation.

CONCLUSION

The five cases presented show the potential benefit of hybrid FLT-PET/MRI for the diagnosis of MBM and treatment monitoring of targeted therapy and immunotherapy. However, further studies are required to assess their complementary role in distinguishing true progression from pseudoprogression.

A randomised trial to compare cognitive outcome after gamma knife radiosurgery versus whole brain radiation therapy in patients with multiple brain metastases: research protocol CAR-study B

BACKGROUND

Gamma Knife radiosurgery (GKRS) is increasingly applied in patients with multiple brain metastases and is expected to have less adverse effects in cognitive functioning than whole brain radiation therapy (WBRT). Effective treatment with the least negative cognitive side effects is increasingly becoming important, as more patients with brain metastases live longer due to more and better systemic treatment options. There are no published randomized trials yet directly comparing GKRS to WBRT in patients with multiple brain metastases that include objective neuropsychological testing.

METHODS

CAR-Study B is a prospective randomised trial comparing cognitive outcome after GKRS or WBRT in adult patients with 11-20 newly diagnosed brain metastases on a contrast-enhanced MRI-scan, KPS ≥70 and life expectancy of at least 3 months. Randomisation by the method of minimization, is stratified by the cumulative tumour volume in the brain, systemic treatment, KPS, histology, baseline cognitive functioning and age. The primary endpoint is the between-group difference in the percentage of patients with significant memory decline at 3 months. Secondary endpoints include overall survival, local control, development of new brain metastases, cognitive functioning over time, quality of life, depression, anxiety and fatigue. Cognitive functioning is assessed by a standardised neuropsychological test battery. Assessments (cognitive testing, questionnaires and MRI-scans) are scheduled at baseline and at 3, 6, 9, 12 and 15 months after treatment.

DISCUSSION

Knowledge gained from this trial may be used to inform individual patients with BM more precisely about the cognitive effects they can expect from treatment, and to assist both doctors and patients in making (shared) individual treatment decisions. This trial is currently recruiting. Target accrual: 23 patients at 3-months follow-up in both groups.

TRIAL REGISTRATION

The Netherlands Trials Register number NTR5463. ClinicalTrials.gov registration number NCT02953717 , first received October 27, 2016, 8 patients were enrolled in this study on 31 July 2017.

5-ALA fluorescence of cerebral metastases and its impact for the local-in-brain progression

Aim of the present study was to analyze the oncological impact of 5-ALA fluorescence of cerebral metastases. A retrospective analysis was performed for 84 patients who underwent 5-ALA fluorescence-guided surgery of a cerebral metastasis. Dichotomized fluorescence behavior was correlated to the histopathological subtype and primary site of the metastases, the degree of surgical resection on an early postoperative MRI within 72 hours after surgery, the local in-brain-progression rate and the overall survival. 34/84 metastases (40.5%) showed either strong or faint and 50 metastases (59.5%) no 5-ALA derived fluorescence. Neither the primary site of the cerebral metastases nor their subtype correlated with fluorescence behavior. The dichotomized 5-ALA fluorescence (yes vs. no) had no statistical influence on the degree of surgical resection. Local in-brain progression within or at the border of the resection cavity was observed in 26 patients (30.9%). A significant correlation between 5-ALA fluorescence and local in-brain-progression rate was observed and patients with 5-ALA-negative metastases had a significant higher risk of local recurrence compared to patients with 5-ALA positive metastases. After exclusion of the 20 patients without any form of adjuvant radiation therapy, there was a trend towards a relation of the 5-ALA behavior on the local recurrence rate and the time to local recurrence, although results did not reach significance anymore. Absence of 5-ALA-induced fluorescence may be a risk factor for local in-brain-progression but did not influence the mean overall survival. Therefore, the dichotomized 5-ALA fluorescence pattern might be an indicator for a more aggressive tumor.

Quantitative analysis in peritumoral volumes of brain metastases treated with stereotactic radiotherapy

PURPOSE

The purpose of this study was to verify changes in diffusion tensor imaging (DTI) factors in patients with brain metastases treated with stereotactic radiotherapy (SRT). We also investigated the impact of SRT on peritumoral volumes though the use of DTI.

METHODS

A total of 28 patients with brain metastases who had undergone SRT between March 2014 and December 2015 were enrolled. Magnetic resonance imaging with DTI factors, such as fractional anisotropy (FA) and apparent diffusion tensor (ADC) value, was performed 1 day before the procedure and 3 months after the procedure. DTI data from tumor lesions, edema volumes, and the volumes that received 12Gy were measured.

RESULTS

Tumor volume (P=0.001) and ADC values in the volumes that received 12Gy (P=0.018) and the edema volumes (P=0.003) significantly decreased after the procedure. Decreases in tumor volume were only correlated with decreases in edema volumes (P<0.001). Decreases in edema volumes were correlated with increases in FA values and decreases in ADC values of the volumes that received 12Gy [P=0.019 (FA)/0.002 (ADC)] and the edema volumes [P=0.011 (FA)/0.002 (ADC)].

CONCLUSIONS

It was possible to quantify changes in peritumoral volumes in patients with brain metastases after SRT by using DTI. ADC values of peritumoral volumes decreased significantly after SRT. Therefore, it was confirmed through DTI that performing SRT on tumor lesions has a positive effect on the structure and function of peritumoral volumes.

Drug Resistance in HER2-Positive Breast Cancer Brain Metastases: Blame the Barrier or the Brain?

The brain is the most common site of first metastasis for patients with HER2-positive breast cancer treated with HER2-targeting drugs. However, the development of effective therapies for breast cancer brain metastases (BCBM) is limited by an incomplete understanding of the mechanisms governing drug sensitivity in the central nervous system. Pharmacodynamic data from patients and in vivo models suggest that inadequate drug penetration across the "blood-tumor" barrier is not the whole story. Using HER2-positive BCBMs as a case study, we highlight recent data from orthotopic brain metastasis models that implicate brain-specific drug resistance mechanisms in BCBMs and suggest a translational research paradigm to guide drug development for treatment of BCBMs. Clin Cancer Res; 24(8); 1795-804. ©2018 AACR.

Identifying candidates for gamma knife radiosurgery among elderly patients with brain metastases

We investigated the outcomes of gamma knife radiosurgery (GKRS) for elderly patients (≥ 65 years) with brain metastases, and identified survival-associated factors. We retrospectively analyzed data from 115 patients treated with GKRS for 1-15 brain metastases. The median patient age was 72 years; most primary tumors were pulmonary (n = 83). The mean lesion volume was 2.1 ± 4.8 mL. A mean dose of 19.3 Gy was delivered to the mean 63.9% isodose line. The median overall survival (OS) was 5.3 months (95% confidence interval [CI] 3.5-7.1). During follow-up (median, 5.1 months), 91 patients died of primary cancer progression while 1 died of unknown causes. The 6- and 12-month local control rates were 94.9 and 88.1%, respectively. On multivariate analysis, female sex (p = 0.005, hazard ratio [HR] 0.533, 95% CI 0.343-0.827) and a controlled primary tumor (p < 0.001, HR 0.328, 95% CI 0.180-0.596) were significantly favorable prognostic factors. Of non-small cell lung cancer patients with EGFR mutations, 76.5% were women (p = 0.005). The median OS of EGFR-mutant and EGFR-wildtype patients were 19.1 and 4.7 months, respectively (p = 0.080). Brain metastases < 3 mL showed better local control rates after GKRS (p = 0.005). GKRS produces favorable outcomes in women with brain metastases who are ≥ 65 years and have controlled primary tumors. Such patients are therefore suitable candidates for GKRS.

Brain metastases: neuroimaging

Magnetic resonance imaging (MRI) is the cornerstone for evaluating patients with brain masses such as primary and metastatic tumors. Important challenges in effectively detecting and diagnosing brain metastases and in accurately characterizing their subsequent response to treatment remain. These difficulties include discriminating metastases from potential mimics such as primary brain tumors and infection, detecting small metastases, and differentiating treatment response from tumor recurrence and progression. Optimal patient management could be benefited by improved and well-validated prognostic and predictive imaging markers, as well as early response markers to identify successful treatment prior to changes in tumor size. To address these fundamental needs, newer MRI techniques including diffusion and perfusion imaging, MR spectroscopy, and positron emission tomography (PET) tracers beyond traditionally used 18-fluorodeoxyglucose are the subject of extensive ongoing investigations, with several promising avenues of added value already identified. These newer techniques provide a wealth of physiologic and metabolic information that may supplement standard MR evaluation, by providing the ability to monitor and characterize cellularity, angiogenesis, perfusion, pH, hypoxia, metabolite concentrations, and other critical features of malignancy. This chapter reviews standard and advanced imaging of brain metastases provided by computed tomography, MRI, and amino acid PET, focusing on potential biomarkers that can serve as problem-solving tools in the clinical management of patients with brain metastases.

PET and SPECT imaging of melanoma: the state of the art

Melanoma represents the most aggressive form of skin cancer, and its incidence continues to rise worldwide. 18F-FDG PET imaging has transformed diagnostic nuclear medicine and has become an essential component in the management of melanoma, but still has its drawbacks. With the rapid growth in the field of nuclear medicine and molecular imaging, a variety of promising probes that enable early diagnosis and detection of melanoma have been developed. The substantial preclinical success of melanin- and peptide-based probes has recently resulted in the translation of several radiotracers to clinical settings for noninvasive imaging and treatment of melanoma in humans. In this review, we focus on the latest developments in radiolabeled molecular imaging probes for melanoma in preclinical and clinical settings, and discuss the challenges and opportunities for future development.

An Update on the Approach to the Imaging of Brain Tumors

PURPOSE OF REVIEW

Neuroimaging plays a critical role in diagnosis of brain tumors and in assessment of response to therapy. However, challenges remain, including accurately and reproducibly assessing response to therapy, defining endpoints for neuro-oncology trials, providing prognostic information, and differentiating progressive disease from post-therapeutic changes particularly in the setting of antiangiogenic and other novel therapies.

RECENT FINDINGS

Recent advances in the imaging of brain tumors include application of advanced MRI imaging techniques to assess tumor response to therapy and analysis of imaging features correlating to molecular markers, grade, and prognosis. This review aims to summarize recent advances in imaging as applied to current diagnostic and therapeutic neuro-oncologic challenges.

Impact of CyberKnife Radiosurgery on Median Overall Survival of Various Parameters in Patients with 1-12 Brain Metastases

Introduction

This study’s objective is to assess various patient, tumor and imaging characteristics and to compare median overall survival (OS) of 150 patients with 1-12 brain metastases post-CyberKnife radiosurgery (CKRS) (Accuray, Sunnyvale, California) alone.

Methods

Charts of 150 patients, from 2009-2014, treated with only CKRS for brain metastases were reviewed retrospectively for patient, tumor, and imaging characteristics. Parameters included demographics, Eastern Cooperative Oncology Group (ECOG) performance scores, number and control of extracranial disease (ECD) sites, cause of death (COD), histology, tumor volume (TV), and post-CKRS whole brain radiotherapy (WBRT). The imaging characteristics assessed were time of complete response (CR), partial response (PR), stable imaging or local failure (LF), and distal brain failure (DBF). The primary tumor Ki-67s of the breast carcinoma brain metastasis patients, who had the longest median OS of any group, were recorded when available.

Results

The predominant age group for the 150-patient cohort was the younger 17-65 years of age category, which was represented by 94 (62.7%). The 150-patient group had slightly more males, 79 (52.7%). The majority of 111 (74%) patients had an ECOG score of 1, 39 (26%) had 1 ECD site and uncontrolled ECD occurred in 112 (74.7%). The main COD was ECD in 106 (70.7%). The prevalent tumor histology was non-small cell lung carcinoma (88 of 150, 58.7%). The most common TV was 0-0.5 ccs (48 of 150, 32%). The majority of 125 (83.3%) patients did not undergo post-CKRS WBRT. Imaging outcomes were local control (LC) (CR, PR, or stable imaging) in 119 (79.3%), of whom 38 (25.3%) had CR, 56 (37.3%) PR and 25 (16.7%) stable imaging; LF was the outcome in 31 (20.7%) and DBF occured in 83 (55.3%). The median OS was 13 months. Patients 17-65 years of age had a median OS of 13 months, while those 66-88 years, had 12 months. Females versus males had median OS of 15 versus 12 months. The most prolonged median OS of 21.5 months occurred in those with an ECOG score of 0. Patients with two ECD sites had a median OS of 14.5 months, while those with controlled ECD, 20.5 months. Patients with breast cancer brain metastases had the longest median OS of 23 months. The median OS for each of three (0-0.5 ccs, 0.6-1.5 ccs, 1.6-4.0 ccs) of four CKRS TV quartiles was 13 months and for those with 4.1-28.5 ccs, 10 months. Median OS for patients with versus without post-CKRS WBRT was 23 versus 12 months. The longest median OS of 18.5 months for post-CKRS imaging outcomes was in patients with CR; those with LF had a median OS of 11.5 months. Of nine patients with breast carcinoma brain metastases with available Ki-67s from primary tumor resections, the Ki-67 values were ≥ 34% for four patients with CR, PR and stable imaging outcomes, and < 34% for five patients with LF.

Conclusions

An ECOG score of 0, ECD control, breast carcinoma brain metastasis histology. undergoing WBRT post-CKRS and CR imaging outcomes, each resulted in a longer median OS. The Ki-67 proliferation indices from primary breast carcinoma resection correlated well with the brain imaging outcomes in a small preliminary study in the present study's breast carcinoma patients with brain metastases.

T-Cell Densities in Brain Metastases Are Associated with Patient Survival Times and Diffusion Tensor MRI Changes

Brain metastases are common and are usually detected by MRI. Diffusion tensor imaging (DTI) is a derivative MRI technique that can detect disruption of white matter tracts in the brain. We have matched preoperative DTI with image-guided sampling of the brain-tumor interface in 26 patients during resection of a brain metastasis and assessed mean diffusivity and fractional anisotropy (FA). The tissue samples were analyzed for vascularity, inflammatory cell infiltration, growth pattern, and tumor expression of proteins associated with growth or local invasion such as Ki67, S100A4, and MMP2, 9, and 13. A lower FA in the peritumoral region indicated more white matter tract disruption and independently predicted longer overall survival times (HR for death = 0.21; 95% confidence interval, 0.06-0.82; P = 0.024). Of all the biological markers studied, only increased density of CD3⁺ lymphocytes in the same region correlated with decreased FA (Mann-Whitney U, P = 0.037) as well as confounding completely the effect of FA on multivariate survival analyses. We conclude that the T-cell response to brain metastases is not a surrogate of local tumor invasion, primary cancer type, or aggressive phenotype and is associated with patient survival time regardless of these biological factors. Furthermore, it can be assayed by DTI, potentially offering a quick, noninvasive, clinically available method to detect an active immune microenvironment and, in principle, to measure susceptibility to immunotherapy.Significance: These findings show that white matter tract integrity is degraded in areas where T-cell infiltration is highest, providing a noninvasive method to identify immunologically active microenvironments in secondary brain tumors. Cancer Res; 78(3); 610-6. ©2017 AACR.

Breast Cancer in the Central Nervous System: Multidisciplinary Considerations and Management

Breast cancer is the second most common primary tumor associated with central nervous system (CNS) metastases. Patients with metastatic HER2-positive or triple-negative (estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, HER2-negative) breast cancer are at the highest risk of developing parenchymal brain metastases. Leptomeningeal disease is less frequent but is distributed across breast cancer subtypes, including lobular breast cancer. Initial treatment strategies can include surgery, radiation, intravenous or intrathecal chemotherapy, and/or targeted approaches. In this article, we review the epidemiology of breast cancer brain metastases, differences in clinical behavior and natural history by tumor subtype, and important considerations in the multidisciplinary treatment of these patients. We will highlight new findings that impact current standards of care, clinical controversies, and notable investigational approaches in clinical testing.

Modernizing Clinical Trial Eligibility Criteria: Recommendations of the American Society of Clinical Oncology-Friends of Cancer Research Brain Metastases Working Group

Purpose Broadening trial eligibility to improve accrual and access and to better reflect intended-to-treat populations has been recognized as a priority. Historically, patients with brain metastases have been understudied, because of restrictive eligibility across all phases of clinical trials. Methods In 2016, after a literature search and series of teleconferences, a multistakeholder workshop was convened. Our working group focused on developing consensus recommendations regarding the inclusion of patients with brain metastases in clinical trials, as part of a broader effort that encompassed minimum age, HIV status, and organ dysfunction. The working group attempted to balance the needs of protecting patient safety, facilitating access to investigational therapies, and ensuring trial integrity. On the basis of input at the workshop, guidelines were further refined and finalized. Results The working group identified three key populations: those with treated/stable brain metastases, defined as patients who have received prior therapy for their brain metastases and whose CNS disease is radiographically stable at study entry; those with active brain metastases, defined as new and/or progressive brain metastases at the time of study entry; and those with leptomeningeal disease. In most circumstances, the working group encourages the inclusion of patients with treated/stable brain metastases in clinical trials. A framework of key considerations for patients with active brain metastases was developed. For patients with leptomeningeal disease, inclusion of a separate cohort in both early-phase and later-phase trials is recommended, if CNS activity is anticipated and when relevant to the specific disease type. Conclusion Expanding eligibility to be more inclusive of patients with brain metastasis is justified in many cases and may speed the development of effective therapies in this area of high clinical need.

Increasing time to postoperative stereotactic radiation therapy for patients with resected brain metastases: investigating clinical outcomes and identifying predictors associated with time to initiation

We sought to determine the impact of time to initiation (TTI) of post-operative radiosurgery on clinical outcomes for patients with resected brain metastases and to identify predictors associated with TTI. All patients with resected brain metastases treated with postoperative SRS or fractionated stereotactic radiation therapy (fSRT) from 2012 to 2016 at a single institution were reviewed. TTI was defined as the interval from resection to first day of radiosurgery. Receiver operating characteristic (ROC) curves were used to identify an optimal threshold for TTI with respect to local failure (LF). Survival outcomes were estimated using the Kaplan-Meier method and analyzed using the log-rank test and Cox proportional hazards models. Logistic regression models were used to identify factors associated with ROC-determined TTI covariates. A total of 79 resected lesions from 73 patients were evaluated. An ROC curve of LF and TTI identified an optimal threshold for TTI of 30.5 days, with an area under the curve of 0.637. TTI > 30 days was associated with an increased hazard of LF (HR 4.525, CI 1.239-16.527) but was not significantly associated with survival (HR 1.002, CI 0.547-1.823) or distant brain failure (DBF, HR 1.943, CI 0.989-3.816). Fifteen patients (20.5%) required post-operative inpatient rehabilitation. Post-operative rehabilitation was associated with TTI > 30 days (OR 1.48, CI 1.142-1.922). In our study of resected brain metastases, longer time to initiation of post-operative radiosurgery was associated with increased local failure. Ideally, post-op SRS should be initiated within 30 days of resection if feasible.

Reviewing RECIST in the Era of Prolonged and Targeted Therapy

Accurate assessment of disease response is the foundation of therapeutic trails, which is why the Response Evaluation Criteria in Solid Tumors (RECIST) serve as an international standard that investigators can utilize when examining patient outcomes. Nine years after the initial RECIST criteria were released, an update, RECIST 1.1, was published to improve on the initial criteria and address technologic advancements in imaging. Since then, advancements in both standard clinical and trial practices, combined with improvements in our understanding of cancer biology, have resulted in the identification of a number of limitations of the current RECIST 1.1, either in lack of clear guidance with regard to its best application or in potential benefit of capturing imaging-related data beyond standard categorical response details. As several of these situations reflect the consequences of prolonged control of metastatic disease by using targeted therapies, thoracic oncology has generated many of the key scenarios requiring elucidation and/or improvements. This article specifically examines current controversies in the interpretation and/or optimal utilization of RECIST 1.1, focusing on examples from thoracic oncology, and makes proposals, where possible, on how best to address these issues. These situations include addressing central nervous system versus extra-central nervous system response and progression, depth of response, oligoprogression versus polyprogression, continuation of systemic therapy after use of a local ablative therapy, and the impact of fluctuations in measurements bridging partial response and stable disease categories during prolonged therapy.

Impact of CyberKnife Radiosurgery on Overall Survival and Various Parameters of Patients with 1-3 versus ≥ 4 Brain Metastases

Introduction

This study’s objective is to compare the overall survivals (OSs) and various parameters of patients with 1-3 versus ≥ 4 brain metastases post-CyberKnife radiosurgery (CKRS) (Accuray, Sunnyvale, California) alone.

Methods

Charts of 150 patients, from 2009-2014, treated with only CKRS for brain metastases were reviewed retrospectively for overall survival (OS) and patient, tumor, and imaging characteristics. Parameters included demographics, Eastern Cooperative Oncology Group (ECOG) performance scores, number and control of extracranial disease (ECD) sites, cause of death (COD), histology, tumor volume (TV), and post-CKRS whole brain radiotherapy (WBRT). The imaging characteristics assessed were time of complete response (CR), partial response (PR), stable imaging or local failure (LF), and distal brain failure (DBF). Patients and their data were divided into those with 1-3 (group 1) versus ≥ 4 brain metastases (group 2). For each CR and LF patient, absolute neutrophil count (ANC), absolute lymphocyte count (ALC)), and ANC/ALC ratio (NLR) were obtained, when available, at the time of CKRS.

Results

Both group 1 and group 2 had a median OS of 13 months. The patient median age for the 115 group 1 patients versus the 35 group 2 patients was 62 versus 56 years. Group 1 had slightly more males and group 2, females. The predominant ECOG score for each group was 1 and the number of ECD sites was one and two, respectively. Uncontrolled ECD occurred in the majority of both group 1 and group 2 patients. The main COD was ECD in both groups. The prevalent tumor histology for groups 1 and 2 was non-small cell lung carcinoma. Median TVs were 1.08 cc versus 1.42 cc for groups 1 and 2, respectively. The majority of patients in both groups did not undergo post-CKRS WBRT. Imaging outcomes were LC (CR, PR, or stable imaging) in 93 (80.9%) and 26 (74.3%) group 1 and 2 patients, of whom 32 (27.8%) and six (17.1%) had CR; 38 (33.0%) and 18 (51.4%), PR and 23 (20.0%) and two (5.7%), stable imaging; LF was the outcome in 22 (19.1%) and nine (25.7%) patients, and DBF occurred in 62 (53.9%) and 21 (60.0%), respectively. Uni- and multivariable analyses showed the independent parameters of a lower ECOG score, a greater number of ECD sites and uncontrolled ECD were significantly associated with greater mortality risk with and without accounting for other covariates. At CKRS, 19 group 1 and 2 CR patients had a mean ANC of 5.88 K/µL and a mean ALC of 1.31 K/µL and 13 (68%) of 19 had NLRs ≤ five, while 11 with LFs had a mean ANC of 5.22 K/µL and a mean ALC of 0.93 K/µL and seven (64%) had NLRs > five. An NLR ≤ five and high ALC was associated with a CR and an NLR > five and a low ALC with an LF.

Conclusions

Median OS post-CKRS was 13 months for both patients with 1-3 brain metastases and with ≥ 4. This is the only study in the literature to evaluate OS in patients with 1-3 and ≥ 4 brain metastases who were treated with CKRS alone. For groups 1 and 2 patients combined, 119 (79.3%) had LC and 38 (25.3%) had CR. The ANC, ALC, and NLR values are likely predictive of CR and LF outcomes

Melanoma brain metastases treated with stereotactic radiosurgery and concurrent pembrolizumab display marked regression; efficacy and safety of combined treatment

Background

Brain metastases are common in patients with metastatic melanoma. With increasing numbers of melanoma patients on anti-PD-1 therapy, we sought to evaluate the safety and initial response of brain metastases treated with concurrent pembrolizumab and radiation therapy.

Methods

From an institutional database, we retrospectively identified patients with melanoma brain metastases treated with radiation therapy (RT) who received concurrent pembrolizumab. Concurrent treatment was defined as RT during pembrolizumab administration period and up to 4 months after most recent pembrolizumab treatment. Response was categorized by change in maximum diameter on first scheduled follow-up MRI. Lesion and patient specific outcomes including response, lesion control, brain control and overall survival were recorded and descriptively compared to contemporary treatments with RT and concurrent ipilimumab or RT without immunotherapy.

Results

From January 2014 through December 2015, we identified 21 patients who received concurrent radiation therapy and pembrolizumab for brain metastases or resection cavities that had at least one scheduled follow-up MRI. Eleven underwent stereotactic radiosurgery (SRS), 7 received hypofractionated radiation and 3 had whole brain treatment (WBRT). All treatments were well tolerated with no observed Grade 4 or 5 toxicities; Grade 3 edema and confusion occurred in 1 patient treated with WBRT after prior SRS. For metastases treated with SRS, at first scheduled follow-up MRI (median 57 days post SRS), 70% (16/23) exhibited complete (CR, n = 8) or partial response (PR, n = 8). The intracranial response rates (CR/PR) for patients treated with SRS and concurrent ipilimumab and SRS without concurrent immunotherapy was 32% and 22%, respectively.

Conclusions

Concurrent pembrolizumab with brain RT appears safe in patients with metastatic melanoma, and SRS in particular is effective in markedly reducing the size of brain metastases at the time of first follow-up MRI. These results compare favorably to SRS in combination with ipilimumab and SRS without concurrent immunotherapy.

Dynamic O-(2-18F-fluoroethyl)-L-tyrosine positron emission tomography differentiates brain metastasis recurrence from radiation injury after radiotherapy

Background

The aim of this study was to investigate the potential of dynamic O-(2-[18F]fluoroethyl)-L-tyrosine (18F-FET) PET for differentiating local recurrent brain metastasis from radiation injury after radiotherapy since contrast-enhanced MRI often remains inconclusive.

Methods

Sixty-two patients (mean age, 55 ± 11 y) with single or multiple contrast-enhancing brain lesions (n = 76) on MRI after radiotherapy of brain metastases (predominantly stereotactic radiosurgery) were investigated with dynamic 18F-FET PET. Maximum and mean tumor-to-brain ratios (TBRmax, TBRmean) of 18F-FET uptake were determined (20-40 min postinjection) as well as tracer uptake kinetics (ie, time-to-peak and slope of time-activity curves). Diagnoses were confirmed histologically (34%; 26 lesions in 25 patients) or by clinical follow-up (66%; 50 lesions in 37 patients). Diagnostic accuracies of PET parameters for the correct identification of recurrent brain metastasis were evaluated by receiver-operating-characteristic analyses or the chi-square test.

Results

TBRs were significantly higher in recurrent metastases (n = 36) than in radiation injuries (n = 40) (TBRmax 3.3 ± 1.0 vs 2.2 ± 0.4, P < .001; TBRmean 2.2 ± 0.4 vs 1.7 ± 0.3, P < .001). The highest accuracy (88%) for diagnosing local recurrent metastasis could be obtained with TBRs in combination with the slope of time-activity curves (P < .001).

Conclusions

The results of this study confirm previous preliminary observations that the combined evaluation of the TBRs of 18F-FET uptake and the slope of time-activity curves can differentiate local brain metastasis recurrence from radiation-induced changes with high accuracy. 18F-FET PET may thus contribute significantly to the management of patients with brain metastases.

Early imaging radioresponsiveness of melanoma brain metastases as a predictor of patient prognosis

OBJECTIVE The aim of this study was to analyze the early radiological response of melanoma brain metastases to single high-dose irradiation and to reveal possible correlations between tumor radioresponsiveness and patient clinical outcomes. METHODS The authors performed a retrospective analysis of the medical data for all patients with melanoma brain metastases who had undergone Gamma Knife radiosurgery (GKRS) and follow-up MRI examinations with standard protocols at regular 2- to 3-month intervals. Volumetric measurements of the metastases on pretreatment and initial posttreatment images were performed to assess the rate of early radiological response. Patients were divided into 2 groups according to the rate of response, and overall survival, local control, and the appearance of new metastases in the brain were compared in these groups using the long-rank test. Univariate and multivariate analyses were performed to identify predictors of clinical outcomes. RESULTS After retrospective analysis of 298 melanoma brain metastases in 78 patients, the authors determined that early radiological responses of these metastases to GKRS differ considerably and can be divided into 2 distinct groups. One group of tumors underwent rapid shrinkage after radiosurgery, whereas the other showed minor fluctuations in size (rapid- and slow-response groups, respectively). Median survival for patients with a slow response was 15.2 months compared with 6.3 months for those with a rapid response (p < 0.0001). In the multivariate analysis, improved overall survival was associated with a slow response to radiosurgery (p < 0.0001), stable systemic disease (p = 0.001), and a higher Karnofsky Performance Scale score (p = 0.001). Stratification by Recursive Partitioning Analysis, score index for radiosurgery, and diagnosis-specific Graded Prognostic Assessment classes further confirmed the difference in overall survival for patients with a slow versus rapid radiation response. Local recurrence was observed in 11% of patients with a rapid response and in 6% of patients with a slow response, at a median of more than 8 months after radiosurgery. New brain metastases were diagnosed in 67% of patients with a slow response at a median of 8.6 months after radiosurgery and in 82% of patients with a rapid response at a considerably earlier median time of 2.7 months. In the multivariate analysis, a longer time to the development of new brain metastases was associated with a slow response (p = 0.012), stable systemic disease (p = 0.034), and a single brain metastasis (p = 0.030). CONCLUSIONS Melanoma brain metastases show different early radioresponsiveness to radiosurgery. Rapid shrinkage of brain metastases is associated with poor patient prognosis, which may indicate more aggressive biological behavior of this tumor phenotype.

First follow-up radiographic response is one of the predictors of local tumor progression and radiation necrosis after stereotactic radiosurgery for brain metastases

Local progression (LP) and radiation necrosis (RN) occur in >20% of cases following stereotactic radiosurgery (SRS) for brain metastases (BM). Expected outcomes following SRS for BM include tumor control/shrinkage, local progression and radiation necrosis. 1427 patients with 4283 BM lesions were treated using SRS at Cleveland Clinic from 2000 to 2012. Clinical, imaging and radiosurgery data were collected from the database. Local tumor progression and RN were the primary end points and correlated with patient and tumor‐related variables. 5.7% of lesions developed radiographic RN and 3.6% showed local progression at 6 months. Absence of new extracranial metastasis (P < 0.001), response to SRS at first follow‐up scan (local progression versus stable size (P < 0.001), partial resolution versus complete resolution at first follow up [P = 0.009]), prior SRS to the same lesion (P < 0.001), IDL% (≤55; P < 0.001), maximum tumor diameter (>0.9 cm; P < 0.001) and MD/PD gradient index (≤1.8, P < 0.001) were independent predictors of high risk of local tumor progression. Absence of systemic metastases (P = 0.029), good neurological function at 1st follow‐up (P ≤ 0.001), no prior SRS to other lesion (P = 0.024), low conformity index (≤1.9) (P = 0.009), large maximum target diameter (>0.9 cm) (P = 0.003) and response to SRS (tumor progression vs. stable size following SRS [P < 0.001]) were independent predictors of high risk of radiographic RN. Complete tumor response at first follow‐up, maximum tumor diameter <0.9 cm, tumor volume <2.4 cc and no prior SRS to the index lesion are good prognostic factors with reduced risk of LP following SRS. Complete tumor response to SRS, poor neurological function at first follow‐up, prior SRS to other lesions and high conformity index are favorable factors for not developing RN. Stable or partial response at first follow‐up after SRS have same impact on local progression and RN compared to those with complete resolution or progression.

Tumor-Treating Fields: A Fourth Modality in Cancer Treatment

Despite major advances in therapy, cancer continues to be a leading cause of mortality. In addition, toxicities of traditional therapies pose a significant challenge to tolerability and adherence. TTFields, a noninvasive anticancer treatment modality, utilizes alternating electric fields at specific frequencies and intensities to selectively disrupt mitosis in cancerous cells. TTFields target proteins crucial to the cell cycle, leading to mitotic arrest and apoptosis. TTFields also facilitate an antitumor immune response. Clinical trials of TTFields have proven safe and efficacious in patients with glioblastoma multiforme (GBM), and are FDA approved for use in newly diagnosed and recurrent GBM. Trials in other localized solid tumors are ongoing. Clin Cancer Res; 24(2); 266-75. ©2017 AACR.

The Treatment of Melanoma Brain Metastases

Melanoma is the malignancy with the highest rate of dissemination to the central nervous system once it metastasizes. Until recently, the prognosis of patients with melanoma brain metastases (MBM) was poor. In recent years, however, the prognosis has improved due to high-resolution imaging that facilitates early detection of small asymptomatic brain metastases and early intervention with local modalities such as stereotactic radiosurgery. More recently, a number of systemic therapies have been approved by the Food and Drug Administration for metastatic melanoma, resulting in improved survival for many MBM patients. Registration trials for these newer therapies excluded patients with untreated brain metastases, and a number of studies specifically tailored to this population of patients have been conducted or are underway. Herein, we review contemporary locoregional and systemic therapies and describe the unique challenges posed by treatment of brain metastases, such as radionecrosis, cerebral edema, and pseudoprogression. Since the number of systemic and combined modality clinical trials has increased, we expect that the treatment landscape for patients with melanoma brain metastasis will change dramatically. In addition to ongoing clinical trials, which show great promise, we conclude that our understanding of intracranial metastasis remains quite limited. In addition to inter-disciplinary, multi-modality studies, bench-side work to better understand the process of cerebrotropism is needed to fuel more drug development and further improve outcomes.

Response Assessment in Neuro-Oncology Clinical Trials

Development of novel therapies for CNS tumors requires reliable assessment of response and progression. This requirement has been particularly challenging in neuro-oncology for which contrast enhancement serves as an imperfect surrogate for tumor volume and is influenced by agents that affect vascular permeability, such as antiangiogenic therapies. In addition, most tumors have a nonenhancing component that can be difficult to accurately quantify. To improve the response assessment in neuro-oncology and to standardize the criteria that are used for different CNS tumors, the Response Assessment in Neuro-Oncology (RANO) working group was established. This multidisciplinary international working group consists of neuro-oncologists, medical oncologists, neuroradiologists, neurosurgeons, radiation oncologists, neuropsychologists, and experts in clinical outcomes assessments, working in collaboration with government and industry to enhance the interpretation of clinical trials. The RANO working group was originally created to update response criteria for high- and low-grade gliomas and to address such issues as pseudoresponse and nonenhancing tumor progression from antiangiogenic therapies, and pseudoprogression from radiochemotherapy. RANO has expanded to include working groups that are focused on other tumors, including brain metastases, leptomeningeal metastases, spine tumors, pediatric brain tumors, and meningiomas, as well as other clinical trial end points, such as clinical outcomes assessments, seizures, corticosteroid use, and positron emission tomography imaging. In an effort to standardize the measurement of neurologic function for clinical assessment, the Neurologic Assessment in Neuro-Oncology scale was drafted. Born out of a workshop conducted by the Jumpstarting Brain Tumor Drug Development Coalition and the US Food and Drug Administration, a standardized brain tumor imaging protocol now exists to reduce variability and improve reliability. Efforts by RANO have been widely accepted and are increasingly being used in neuro-oncology trials, although additional refinements will be needed.

Treatment of brain metastasis: current status and future directions

PURPOSE OF REVIEW

The purpose of this review is to highlight the most recent advances in the management of brain metastases.

RECENT FINDINGS

Role of local therapies (surgery and stereotactic radiosurgery), new approaches to minimize cognitive sequelae following whole-brain radiotherapy and advances in targeted therapies have been reviewed.

SUMMARY

The implications for clinical trials and daily practice of the increasing use of stereotactic radiosurgery in multiple brain metastases and upfront targeted agents in asymptomatic brain metastases are discussed.

Cumulative Intracranial Tumor Volume and Number of Brain Metastasis as Predictors of Developing New Lesions After Stereotactic Radiosurgery for Brain Metastasis

OBJECTIVES

To identify risk factors associated with early distant radiographic progression in patients undergoing stereotactic radiosurgery (SRS) for brain metastases (BM).

METHODS

Following Institutional Review Board approval, data of 1427 patients (4283 BM lesions) who were treated by SRS at the Cleveland Clinic for 2000-2012 were collected. Local tumor progression (LTP), distant tumor progression (DTP), and radiographic radiation necrosis (RN) were the primary endpoints. Patient, imaging, radiosurgery, and tumor variables and follow-up data were collected.

RESULTS

The median number of targets was 2 (range, 1-17); 45% of the patients had a single lesion. DTP was observed in 10% at 3 months and 19% at 6 months. Patients with 5-10 target lesions for SRS were more likely to develop new lesions at both 3 and 6 months compared to those with 2-4 lesions (odds ratio [OR], 0.83, 95% confidence interval [CI], 0.40-0.85 and OR, 0.85, 95% CI, 0.45-0.86 respectively; P < 0.05). Younger age (<65 years; P < 0.001), higher number of lesions (>1; P < 0.001), cumulative intracranial tumor volume (CITV) <2.75 cc (P = 0.023), type of SRS (upfront and salvage vs. boost; P < 0.001), and tumor pathology (radiosensitive; P < 0.001), were independent predictors of early distant tumor progression following SRS.

CONCLUSIONS

The number of target lesions and low CITV are both independent predictors of early DTP following SRS for BM. Radiosensitive tumor histology, younger age (<65 years), and SRS without previous whole-brain radiation therapy (upfront or salvage) were also predictors of early DTP.

Efficacy of alectinib in central nervous system metastases in crizotinib-resistant ALK-positive non-small-cell lung cancer: Comparison of RECIST 1.1 and RANO-HGG criteria

BACKGROUND

Central nervous system (CNS) progression is common in patients with anaplastic lymphoma kinase-positive (ALK+) non-small-cell lung cancer (NSCLC) receiving crizotinib. Next-generation ALK inhibitors have shown activity against CNS metastases, but accurate assessment of response and progression is vital. Data from two phase II studies in crizotinib-refractory ALK+ NSCLC were pooled to examine the CNS efficacy of alectinib, a CNS-active ALK inhibitor, using Response Evaluation Criteria in Solid Tumours (RECIST version 1.1) and Response Assessment in Neuro-Oncology high-grade glioma (RANO-HGG) criteria.

METHODS

Both studies enrolled patients aged ≥18 years who had previously received crizotinib. NP28761 was conducted in North America and NP28673 was a global study. All patients received 600 mg oral alectinib twice daily and had baseline CNS imaging. CNS response for those with baseline CNS metastases was determined by an independent review committee.

RESULTS

Baseline measurable CNS disease was identified in 50 patients by RECIST and 43 by RANO-HGG. CNS objective response rate was 64.0% by RECIST (95% confidence interval [CI]: 49.2-77.1; 11 CNS complete responses [CCRs]) and 53.5% by RANO-HGG (95% CI: 37.7-68.8; eight CCRs). CNS responses were durable, with consistent estimates of median duration of 10.8 months with RECIST and 11.1 months with RANO-HGG. Of the 39 patients with measurable CNS disease by both RECIST and RANO-HGG, only three (8%) had CNS progression according to one criteria but not the other (92% concordance rate).

CONCLUSION

Alectinib demonstrated promising efficacy in the CNS for ALK+ NSCLC patients pretreated with crizotinib, regardless of the assessment criteria used.

Stereotactic radiosurgery alone for multiple brain metastases? A review of clinical and technical issues

Over the past three decades several randomized trials have enabled evidence-based practice for patients presenting with limited brain metastases. These trials have focused on the role of surgery or stereotactic radiosurgery (SRS) with or without whole brain radiation therapy (WBRT). As a result, it is clear that local control should be optimized with surgery or SRS in patients with optimal prognostic factors presenting with up to 4 brain metastases. The routine use of adjuvant WBRT remains debatable, as although greater distant brain control rates are observed, there is no impact on survival, and modern outcomes suggest adverse effects from WBRT on patient cognition and quality of life. With dramatic technologic advances in radiation oncology facilitating the adoption of SRS into mainstream practice, the optimal management of patients with multiple brain metastases is now being put forward. Practice is evolving to SRS alone in these patients despite a lack of level 1 evidence to support a clinical departure from WBRT. The purpose of this review is to summarize the current state of the evidence for patients presenting with limited and multiple metastases, and to present an in-depth analysis of the technology and dosimetric issues specific to the treatment of multiple metastases.

Prolonged survival in patients with breast cancer and a history of brain metastases: results of a preplanned subgroup analysis from the randomized phase III BEACON trial

Purpose

Conventional chemotherapy has limited activity in patients with breast cancer and brain metastases (BCBM). Etirinotecan pegol (EP), a novel long-acting topoisomerase-1 inhibitor, was designed using advanced polymer technology to preferentially accumulate in tumor tissue including brain metastases, providing sustained cytotoxic SN38 levels.

Methods

The phase 3 BEACON trial enrolled 852 women with heavily pretreated locally recurrent or metastatic breast cancer between 2011 and 2013. BEACON compared EP with treatment of physician’s choice (TPC; eribulin, vinorelbine, gemcitabine, nab-paclitaxel, paclitaxel, ixabepilone, or docetaxel) in patients previously treated with anthracycline, taxane, and capecitabine, including those with treated, stable brain metastases. The primary endpoint, overall survival (OS), was assessed in a pre-defined subgroup of BCBM patients; an exploratory post hoc analysis adjusting for the diagnosis-specific graded prognostic assessment (GPA) index was also conducted.

Results

In the trial, 67 BCBM patients were randomized (EP, n = 36; TPC, n = 31). Treatment subgroups were balanced for baseline characteristics and GPA indices. EP was associated with a significant reduction in the risk of death (HR 0.51; P < 0.01) versus TPC; median OS was 10.0 and 4.8 months, respectively. Improvement in OS was observed in both poorer and better GPA prognostic groups. Survival rates at 12 months were 44.4% for EP versus 19.4% for TPC. Consistent with the overall BEACON population, fewer patients on EP experienced grade ≥3 toxicity (50 vs. 70%).

Conclusions

The significant improvement in survival in BCBM patients provides encouraging data for EP in this difficult-to-treat subgroup of patients. A phase three trial of EP in BCBM patients is underway (ClinicalTrials.gov NCT02915744).

Electronic supplementary material

The online version of this article (doi:10.1007/s10549-017-4304-7) contains supplementary material, which is available to authorized users.

The Neurologic Assessment in Neuro-Oncology (NANO) scale: a tool to assess neurologic function for integration into the Response Assessment in Neuro-Oncology (RANO) criteria

Background

The Macdonald criteria and the Response Assessment in Neuro-Oncology (RANO) criteria define radiologic parameters to classify therapeutic outcome among patients with malignant glioma and specify that clinical status must be incorporated and prioritized for overall assessment. But neither provides specific parameters to do so. We hypothesized that a standardized metric to measure neurologic function will permit more effective overall response assessment in neuro-oncology.

Methods

An international group of physicians including neurologists, medical oncologists, radiation oncologists, and neurosurgeons with expertise in neuro-oncology drafted the Neurologic Assessment in Neuro-Oncology (NANO) scale as an objective and quantifiable metric of neurologic function evaluable during a routine office examination. The scale was subsequently tested in a multicenter study to determine its overall reliability, inter-observer variability, and feasibility.

Results

The NANO scale is a quantifiable evaluation of 9 relevant neurologic domains based on direct observation and testing conducted during routine office visits. The score defines overall response criteria. A prospective, multinational study noted a >90% inter-observer agreement rate with kappa statistic ranging from 0.35 to 0.83 (fair to almost perfect agreement), and a median assessment time of 4 minutes (interquartile range, 3-5).

Conclusion

The NANO scale provides an objective clinician-reported outcome of neurologic function with high inter-observer agreement. It is designed to combine with radiographic assessment to provide an overall assessment of outcome for neuro-oncology patients in clinical trials and in daily practice. Furthermore, it complements existing patient-reported outcomes and cognition testing to combine for a global clinical outcome assessment of well-being among brain tumor patients.

Single-Fraction Stereotactic Radiosurgery (SRS) Alone Versus Surgical Resection and SRS for Large Brain Metastases: A Multi-institutional Analysis

PURPOSE

Stereotactic radiosurgery (SRS) dose is limited by brain metastasis (BM) size. The study goal was to retrospectively determine whether there is a benefit for intracranial outcomes and overall survival (OS) for gross total resection with single-fraction SRS versus SRS alone for patients with large BMs.

METHODS AND MATERIALS

A large BM was defined as ≥4 cm³ (2 cm in diameter) prior to the study. We reviewed the records of consecutive patients treated with single-fraction SRS alone or surgery with preoperative or postoperative SRS between 2005 and 2013 from 2 institutions.

RESULTS

Overall, 213 patients with 223 treated large BMs were included; 66 BMs (30%) were treated with SRS alone and 157 (70%) with surgery and SRS (63 preoperatively and 94 postoperatively). The groups (SRS vs surgery and SRS) were well balanced except regarding lesion volume (median, 5.9 cm³ vs 9.6 cm³; P<.001), median number of BMs (1.5 vs 1, P=.002), median SRS dose (18 Gy vs 15 Gy, P<.001), and prior whole-brain radiation therapy (33% vs 5%, P<.001). The local recurrence (LR) rate was significantly lower with surgery and SRS (1-year LR rate, 36.7% vs 20.5%; P=.007). There was no difference in radiation necrosis (RN) by resection status, but there was a significantly increased RN rate with postoperative SRS versus with preoperative SRS and with SRS alone (1-year RN rate, 22.6% vs 5% and 12.3%, respectively; P<.001). OS was significantly higher with surgery and SRS (2-year OS rate, 38.9% vs 19.8%; P=.01). Both multivariate adjusted analyses and propensity score-matched analyses demonstrated similar results.

CONCLUSIONS

In this retrospective study, gross total resection with SRS was associated with significantly reduced LR compared with SRS alone for patients with large BMs. Postoperative SRS was associated with the highest rate of RN. Surgical resection with SRS may improve outcomes in patients with a limited number of large BMs compared with SRS alone. Further studies are warranted.

Radiosurgery/stereotactic radiotherapy in combination with immunotherapy and targeted agents for melanoma brain metastases

INTRODUCTION

The clinical landscape of advanced melanoma drastically changed after the introduction of both targeted therapies and immunotherapy. This rapid development in systemic therapies led to a change in the management of patients with brain metastases, with the subsequent need to re-assess the role of local therapies, in particular stereotactic radiosurgery (SRS). Areas covered: In this non-systematic review, we report on the current knowledge on the use of SRS in combination with immunotherapy and BRAF/MEK inhibitors for patients with melanoma brain metastases, as well as ongoing trials in this field. Expert commentary: It is now more common to observe patients with melanoma brain metastases with better performance status and prolonged life expectancy. A combination of targeted therapy and immunotherapy, in different sequences, has been shown to be feasible and well tolerable, on the basis of retrospective reports. Additional data from ongoing prospective trials are however needed to confirm or not these findings and better explore the efficacy of the combination.

Evaluating tumor response with FDG PET: updates on PERCIST, comparison with EORTC criteria and clues to future developments

Eighteen years ago, the EORTC PET criteria standardized for the first time response assessment by FDG PET. Response assessment by FDG PET has been further developed and refined by PERCIST (PET response criteria in solid tumors). This review describes the data underlying these two systems for assessing tumor response on FDG PET/CT. It also summarizes recent clinical studies that have compared EORTC criteria and PERCIST with each other as well as with the anatomically based "response criteria in solid tumors" (RECIST). These studies have shown that response assessment by EORTC criteria and PERCIST leads to very similar response classifications. In contrast, there are significant differences between response assessment by PERCIST and RECIST. Preliminary data also suggest that response assessment by PERCIST is better correlated with patient outcome and may be a better predictor for the effectiveness of new anti-cancer therapies than RECIST. If correct, this could have a significant impact on oncologic drug development. However, confirmation of the better predictive value of response assessment by PERCIST by data from randomized trials is still lacking.

Combination of immune checkpoint inhibitors and radiotherapy: Review of the literature

Literature experiences in cancer treatment usually deal with either targeting the tumour cell or the immune system, which often fail to reach the curative purposes in many solid tumours. On the other hand, one mechanism of radiation-induced tumour control is the activation of the adaptive immune system by tumour antigen release following radiotherapy. So, combining radiation therapy with immune checkpoint blockade treatment at the same time may represent a way to stimulate the adaptive immune system, with further amplification of immune responses reached through systemic immune checkpoint blockade. Until now, only few studies deal with the association of immune checkpoint blockade treatment and radiotherapy. In this review, we evaluate this association, highlighting this possibility as a new strategy to improve outcome in cancer patients.

Comparing available criteria for measuring brain metastasis response to immunotherapy

The response assessment in neuro-oncology (RANO) working group recently proposed standardized response criteria for brain metastases (RANO-BM). We sought to compare RANO-BM to other criteria in an ongoing brain metastasis trial. The first 36 patients enrolled on NCT02085070, an ongoing trial of pembrolizumab for patients with untreated brain metastases, were included in this analysis. As RANO-BM had not been proposed when the protocol was written, response on trial was assessed using an institutional modification of RECIST 1.1 (mRECIST), wherein minimum target brain lesion size was 5 mm in longest diameter and up to five target brain lesions were followed. We here additionally assessed response using standard RECIST 1.1, RANO high-grade glioma (RANO-HGG), and RANO-BM. Comparison between the four criteria sets using cases eligible across the board revealed excellent concordance (kappa statistic > 0.8), with only one discordant case. However, compared to RECIST 1.1 or RANO-BM, using a 5 mm threshold for target brain lesions in mRECIST allowed enrollment of 13 additional patients, five of whom had durable responses. Compared to RANO-HGG, 19 additional patients were enrolled using mRECIST, eight of whom had durable responses. Consequently, this resulted in response rates ranging from 12% with RANO-HGG to 28% with mRECIST. This study supports using a 5 mm threshold for target brain lesions when using high resolution MRI with ≤2 mm slices to facilitate accrual to similar clinical trials and provide earlier access to novel therapies for brain metastasis patients. Concordance among the four criteria studied was otherwise very high.

Perilesional edema in brain metastasis from non-small cell lung cancer (NSCLC) as predictor of response to radiosurgery (SRS)

Radiosurgery (SRS) is widely used in the treatment of brain oligo-metastases from NSCLC. The aim of present study is to evaluate the extent of perilesional edema in brain metastases as predictive factor of treatment response. This single center retrospective study included 42 consecutive patients (January 2011-December 2014) with 1-2 brain metastasis from NSCLC treated with Radiosurgery (SRS). Extent of perilesional edema was measured as maximal extension from the edge of lesion and classified as minor (<10 mm) or major (≥10 mm). We analyzed Modality of Brain Recurrence (MBR), classified as in-field or out-of- field, and Brain Progression Free-Survival (BPFS) after treatment stratified according to extent of perilesional edema. Analyzing modality of brain recurrence and BPFS, after a median follow-up of 6 months, we found that patients with minor edema had a better radiological response to SRS with none in-field recurrences and a lower risk of the onset of new brain lesions (out-of-field recurrence). Instead, patients group with major edema had a worse response rate of lesions treated, further, a higher risk of out-of-field brain relapse. Extent of perilesional edema in brain metastasis from NSCLC could be a predictive factor of response and brain progression after SRS treatment alone.

Dynamic contrast-enhanced MR imaging pharmacokinetic parameters as predictors of treatment response of brain metastases in patients with lung cancer

OBJECTIVES

To determine the diagnostic accuracy of pharmacokinetic parameters measured by dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in predicting the response of brain metastases to antineoplastic therapy in patients with lung cancer.

METHODS

Forty-four consecutive patients with lung cancer, harbouring 123 newly diagnosed brain metastases prospectively underwent conventional 3-T MRI at baseline (within 1 month before treatment), during the early (7-10 weeks) and midterm (5-7 months) post-treatment period. An additional DCE MRI sequence was performed during baseline and early post-treatment MRI to evaluate baseline pharmacokinetic parameters (K ^trans, k _ep, v _e, v _p) and their early variation (∆K ^trans, ∆k _ep, ∆v _e, ∆v _p). The objective response was judged by the volume variation of each metastasis from baseline to midterm MRI. ROC curve analysis determined the best DCE MRI parameter to predict the objective response.

RESULTS

Baseline DCE MRI parameters were not associated with the objective response. Early ∆K ^trans, ∆v _e and ∆v _p were significantly associated with the objective response (p = 0.02, p = 0.001 and p = 0.02, respectively). The best predictor of objective response was ∆v _e with an area under the curve of 0.93 [95% CI = 0.87, 0.99].

CONCLUSIONS

DCE MRI and early ∆v _e may be a useful tool to predict the objective response of brain metastases in patients with lung cancer.

KEY POINTS

• DCE MRI could predict the response of brain metastases from lung cancer • ∆v _e was the best predictor of response • DCE MRI could be used to individualize patients' follow-up.

High-resolution whole-brain DCE-MRI using constrained reconstruction: Prospective clinical evaluation in brain tumor patients

PURPOSE

To clinically evaluate a highly accelerated T1-weighted dynamic contrast-enhanced (DCE) MRI technique that provides high spatial resolution and whole-brain coverage via undersampling and constrained reconstruction with multiple sparsity constraints.

METHODS

Conventional (rate-2 SENSE) and experimental DCE-MRI (rate-30) scans were performed 20 minutes apart in 15 brain tumor patients. The conventional clinical DCE-MRI had voxel dimensions 0.9 × 1.3 × 7.0 mm(3), FOV 22 × 22 × 4.2 cm(3), and the experimental DCE-MRI had voxel dimensions 0.9 × 0.9 × 1.9 mm(3), and broader coverage 22 × 22 × 19 cm(3). Temporal resolution was 5 s for both protocols. Time-resolved images and blood-brain barrier permeability maps were qualitatively evaluated by two radiologists.

RESULTS

The experimental DCE-MRI scans showed no loss of qualitative information in any of the cases, while achieving substantially higher spatial resolution and whole-brain spatial coverage. Average qualitative scores (from 0 to 3) were 2.1 for the experimental scans and 1.1 for the conventional clinical scans.

CONCLUSIONS

The proposed DCE-MRI approach provides clinically superior image quality with higher spatial resolution and coverage than currently available approaches. These advantages may allow comprehensive permeability mapping in the brain, which is especially valuable in the setting of large lesions or multiple lesions spread throughout the brain.