Management of patients with brain metastases from non-small cell lung cancer and adverse prognostic features: multi-national radiation treatment recommendations are heterogeneous

Outcomes of Patients with Non-Small Cell Lung Cancer and Brain Metastases Treated with the Upfront Single Agent Pembrolizumab: A Retrospective and Multicentric Study of the ESCKEYP GFPC Cohort

Non-small cell lung cancer (NSCLC) is the most common cause of brain metastasis (BM). Little is known about immune checkpoint inhibitor activity in the central nervous system, especially in patients receiving monotherapy for tumors with a tumor proportion score (TPS) ≥ 50%. This noninterventional, retrospective, multicenter study, conducted with the GFPC, included treatment-naïve patients strongly positive for PD-L1 (TPS ≥ 50%) with BM receiving first-line single-agent pembrolizumab treatment between May 2017 and November 2019. The primary endpoints were centrally reviewed intracranial overall response rates (ORRs), centrally reviewed intracranial progression-free survival (cPFS), extracranial PFS, and overall survival were secondary endpoints. Forty-three patients from five centers were included. Surgical or local radiation therapy was administered to 31 (72%) patients, mostly before initiating ICI therapy (25/31). Among 38/43 (88.4%) evaluable patients, the intracranial ORR was 73%. The median PFS was 8.3 months. The cerebral and extracerebral median PFS times were 9.2 and 5.3 months, respectively. The median OS was 25.5 months. According to multivariate analysis, BM surgery before ICI therapy was the only factor significantly associated with both improved PFS (HR = 0.44) and OS (HR = 0.45). This study revealed the feasibility and outcome of front-line pembrolizumab treatment in this population with BM.

Evaluation of Potential Predictive Biomarkers for Defining Brain Radiotherapy Efficacy in Non-Small Cell Lung Cancer Patients with Brain Metastases: A Case Report and a Narrative Review

Non-small cell lung cancer (NSCLC) is the second most common cancer worldwide, resulting in 1.8 million deaths per year. Most patients are diagnosed with a metastatic disease. Brain metastases are one of the most common metastatic sites and are associated with severe neurological symptoms, shorter survival, and the worst clinical outcomes. Brain radiotherapy and systemic oncological therapies are currently used for controlling both cancer progression and neurological symptoms. Brain radiotherapy includes stereotactic brain ablative radiotherapy (SBRT) or whole brain radiotherapy (WBRT). SBRT is applied for single or multiple (up to ten) small (diameter less than 4 cm) lesions, whereas WBRT is usually applied for multiple (more than ten) and large (diameter greater than 4 cm) brain metastases. In both cases, radiotherapy application may be viewed as an overtreatment which causes severe toxicities without achieving a significant clinical benefit. Thus far, a number of scoring systems to define the potential clinical benefits derived from brain radiotherapy have been proposed. However, most are not well established in clinical practice. In this article, we present a clinical case of a patient with advanced NSCLC carrying a BRAFV600E mutation and brain metastases. We review the variables in addition to applicable scoring systems considered to have potential for predicting clinical outcomes and benefits of brain radiotherapy in patients with advanced NSCLC and brain metastases. Lastly, we highlight the unmet need of specific scoring systems for advanced NSCLC patients with brain metastases carrying oncogene alterations including BRAFV600E mutations.

How we treat octogenarians with brain metastases

Biologically younger, fully independent octogenarians are able to tolerate most oncological treatments. Increasing frailty results in decreasing eligibility for certain treatments, e.g., chemotherapy and surgery. Most brain metastases are not an isolated problem, but part of widespread cancer dissemination, often in combination with compromised performance status. Multidisciplinary assessment is key in this vulnerable patient population where age, frailty, comorbidity and even moderate additional deficits from brain metastases or their treatment may result in immobilization, hospitalization, need for nursing home care, termination of systemic anticancer treatment etc. Here, we provide examples of successful treatment (surgery, radiosurgery, systemic therapy) and best supportive care, and comment on the limitations of prognostic scores, which often were developed in all-comers rather than octogenarians. Despite selection bias in retrospective studies, survival after radiosurgery was more encouraging than after whole-brain radiotherapy. Prospective research with focus on octogenarians is warranted to optimize outcomes.

Brain Metastases: Is There Still a Role for Whole-Brain Radiation Therapy?

Whole-brain radiation therapy (WBRT) has commonly been prescribed to palliate symptoms from brain metastases, to reduce the risk of local relapse after surgical resection, and to improve distant brain control after resection or radiosurgery. While targeting micrometastases throughout the brain can be considered advantageous, the simultaneous exposure of healthy brain tissue might cause adverse events. Attempts to mitigate the risk of neurocognitive decline after WBRT include the selective avoidance of the hippocampi, among others. Besides selective dose reduction, dose escalation to boost volumes, for example, simultaneous integrated boost, aiming at increased tumor control probability is technically feasible. While up-front radiotherapy for newly diagnosed brain metastases often employs radiosurgery or other techniques targeting visible lesions only, sequential (delayed) salvage treatment with WBRT might still become necessary. In addition, the presence of leptomeningeal tumors or very widespread parenchymatous brain metastases might prompt clinicians to prescribe early WBRT.

Tackling brain metastases from lung cancer during the COVID-19 pandemic

Given the enormous strain the COVID-19 pandemic has put on healthcare worldwide, appropriate allocation of resources according to priority is of immense importance. As brain metastases are a common presentation in lung cancer, during the pandemic, it potentially can pose a major management challenge to clinicians. In this article, we outline a pragmatic approach that oncologists should consider while managing these patients. The overarching principle is to deliver best, evidence-based treatment without compromising patient care while ensuring the safety of healthcare workers.

Primary systemic therapy for patients with brain metastases from lung cancer ineligible for targeted agents

Purpose

The purpose of this study was to evaluate overall survival after systemic therapy, largely chemotherapy, in patients with small cell or non-small cell lung cancer and brain metastases. After completion of systemic therapy, some patients received planned brain irradiation, while others were followed.

Methods

Retrospective cohort study.

Results

Thirty-eight patients were included (28 small cell, 20 followed with imaging). Six of these 20 patients (30%) received delayed radiotherapy during follow-up. Planned radiotherapy (n = 18, intention-to-treat) was associated with longer survival from diagnosis of brain metastases, median 10.8 versus 6.1 months, p = 0.025. Delayed radiotherapy still resulted in numerically better survival than no radiotherapy at all (median 8.8 versus 5.3 months, not significant). If calculated from the start of delayed radiotherapy, median survival was only 2.7 months. In a multivariable analysis, both Karnofsky performance status ≥ 70 (p = 0.03) and planned radiotherapy (p = 0.05) were associated with better survival.

Conclusion

In patients ineligible for targeted agents, planned radiotherapy in a modern treatment setting was associated with longer survival compared to no radiotherapy. Timing and type of radiotherapy in such patients should be evaluated in prospective trials to identify patients who might not need planned radiotherapy.

A Case of Five-Year Survival After Combined-Modality Treatment for Non-Small Cell Lung Cancer With Intraspinal Metastasis

This case report describes the treatment approach and outcome in a 69-year-old female patient with non-small cell lung cancer (NSCLC) diagnosed with T4 N2 M1b (intraspinal) disease. The two most common targets for tyrosine kinase inhibitors (epidermal growth factor receptor and anaplastic lymphoma kinase) were not expressed. Programmed death-ligand 1 (PD-L1) was expressed in <50% of the tumor cells. In 2016, initial guideline-concordant treatment with carboplatin/vinorelbine chemotherapy was initiated. Between the first two cycles, all positron emission tomography (PET) positive lesions were irradiated with 30 Gy in 10 fractions (lung, nodes, thoracic spinal manifestation). After nine months with excellent response (at least partial remission, possibly fibrosis only), bilateral lung metastases were diagnosed. The patient was started on nivolumab monotherapy (later atezolizumab due to a change in National practice) and completed two years of treatment. She is currently in continued complete remission with regular follow-up examinations. This case illustrates that outcomes comparable to those observed in patients with limited brain metastases may be observed in patients with localized intraspinal disease and that immune checkpoint inhibitors play an important role in the management of metastatic NSCLC.

The LabBM score is an excellent survival prediction tool in patients undergoing palliative radiotherapy

Background and aim

The prognostic assessment of patients referred for palliative radiotherapy can be conducted by site-specific scores. A quick assessment that would cover the whole spectrum could simplify the working day of clinicians who are not specialists for a particular disease site. This study evaluated a promising score, the LabBM (validated for brain metastases), in patients treated for other indications.

Materials and methods

The LabBM score was calculated in 375 patients by assigning 1 point each for C-reactive protein and lactate dehydrogenase above the upper limit of normal, and 0.5 points each for hemoglobin, platelets and albumin below the lower limit of normal. Uni- and multivariate analyses were performed.

Results

Median overall survival gradually decreased with increasing point sum (range 25.1-1.1 months). When grouped according to the original three-tiered model, excellent discrimination was found. Patients with 0-1 points had a median survival of 15.7 months. Those with 1.5-2 points had a median survival of 5.8 months. Finally, those with 2.5-3.5 points had a median survival of 3.2 months (all p-values ≤ 0.001).

Conclusion

The LabBM score, which is derived from inexpensive blood tests and easy to use, stratified patients into three very distinct prognostic groups and deserves further validation.

Assessment of extracranial metastatic disease in patients with brain metastases: How much effort is needed in the context of evolving survival prediction models?

Survival prediction models may serve as decision-support tools for clinicians who have to assign the right treatment to each patient, in a manner whereby harmful over- or undertreatment is avoided as much as possible. Current models differ regarding their components, the overall number of components and the weighting of individual components. Some of the components are easy to assess, such as age or primary tumor type. Others carry the risk of inter-assessor inconsistency and time-dependent variation. The present publication focuses on issues related to assessment of extracranial metastases and potential surrogates, e.g. blood biomarkers. It identifies areas of controversy and provides recommendations for future research projects, which may contribute to prognostic models with improved accuracy.

Expansion of the LabBM Score: Is the LabPS the Best Tool Predicting Survival in Patients With Brain Metastases?

OBJECTIVES

The objective of this study were to improve the 3-tiered, purely biomarker-based LabBM score, which predicts the survival of patients with brain metastases, by adding the well-established prognostic factor performance status (PS), and to define its role in comparison with the recently proposed Extracranial-Graded Prognostic Assessment score, which is based on the well-known Diagnosis-specific Graded Prognostic Assessment and 2 of the same biomarkers.

MATERIALS AND METHODS

This was a retrospective single-institution analysis of 212 patients, managed with upfront brain irradiation. Survival was stratified by LabBM and LabPS score. Each included serum hemoglobin, platelets, albumin, C-reactive protein, and lactate dehydrogenase (plus PS for the LabPS). Zero, 0.5, or 1 point was assigned and the final point sum calculated. A higher point sum indicates shorter survival.

RESULTS

The new LabPS score predicted overall survival very well (median: 12.1 to 0.7 mo, 1-y rate: 52% to 0%), P=0.0001. However, the group with the poorest prognosis (3 or 3.5 points) was very small (4%). Most patients with comparably short survival had a lower point sum. The LabPS score failed to outperform the recently proposed Extracranial-Graded Prognostic Assessment score.

CONCLUSIONS

Integration of blood biomarkers should be considered when attempting to develop improved scores. Additional research is needed to improve the tools which predict short survival, because many of these patients continue to go undetected with all available scores.

Recursive Partitioning Analysis of Systemic Therapy after Radiotherapy in Patients with Brain Metastases

PURPOSE

The purpose of this study was to identify factors associated with the initiation or continuation of systemic treatment after brain irradiation. The outcome of interest was a utilization rate of at least 75%, given that active extracranial disease is common in patients with brain metastases. If left untreated, extracranial disease limits survival, regardless of successful local treatment of the brain metastases. In this context, systemic therapy has been shown to improve survival, e.g., after whole-brain radiotherapy.

PATIENTS AND METHODS

The study included 185 patients with active extracranial disease, 60% of whom received systemic therapy.

RESULTS

Survival from the start of brain irradiation was longest in patients who received additional immune checkpoint inhibitors, endocrine treatment, or anti-HER-2 drugs. After uni- and multivariate analyses, Eastern Cooperative Oncology Group performance status (PS) was selected as the first prediction criterion in the recursive partitioning analysis (RPA) decision tree analysis. RPA was successful for patients with PS 0-1, but patients with PS 2 had lower treatment utilization rates (maximum 60-70%, with a disease-dependent impact of age and LabBM score [blood test results]). The highest utilization rates were observed in (1) patients with PS 0 and (2) those with breast cancer, small-cell lung cancer, or lung adenocarcinoma with PS 1.

CONCLUSIONS

These results inform the multidisciplinary discussion and treatment planning for the common scenario of simultaneous intra- and extracranial metastases.

Stereotactic Radiosurgery of Brain Metastasis in Patients with a Poor Prognosis: Effective or Overtreatment?

Purpose

Stereotactic radiosurgery (SRS) of brain metastasis in patients with a poor prognosis remains controversial. Here, we compared results of SRS alone to whole brain radiotherapy (WBRT) in poor-prognosis patients and defined the most important unfavorable prognostic factors related to early death after SRS alone.

Patients and Methods

In this retrospective analysis of prospective SRS data, 180 patients with brain metastases not previously treated with WBRT were analyzed. Results of SRS were compared to WBRT by propensity score matching in patients with a poor prognosis defined by graded prognostic assessment (GPA) <2. Further, SRS patients were divided into training (n=82) and validation (n=48) cohorts. Overall survival (OS) and the risk of early death were defined by univariable and multivariable analyses.

Results

Median survival of the WBRT and SRS cohorts was 86 days (IQR: 38-172 days) and 201 days (IQR: 86-not reached), respectively (p<0.0001). OS in patients with GPA<2 was significantly longer in the SRS vs WBRT group (123 vs 58 days; p=0.008). Survival was longer in the SRS group in a propensity score matched analysis. In multivariable analysis, GPA (OR: 0.44, 95%CI: 0.21-0.95; p=0.001), extensive extracranial disease (OR: 0.13, 95%CI: 0.02-0.66; p=0.013), and serious neurological deficits (OR: 0.13, 95%CI: 0.04-0.45; p=0.001) were associated with early death. If one factor was favorable, 73% (training) and 92% (validation) of patients survived three months. Patients with GPA <2 presenting with serious neurological deficits and extensive extracranial disease had a low expected benefit due to the highest risk of death within three months (AUC: 0.822 training; 0.932 validation).

Conclusion

SRS is a viable treatment option for patients with a poor prognosis defined as GPA <2. Good neurological status, extracranial oligometastatic disease, or GPA ≥2 should be present to justify SRS in patients with brain metastases.

Symptom Burden in Patients With Reduced Performance Status at the Start of Palliative Radiotherapy

BACKGROUND/AIM

Previous research has suggested that palliative radiotherapy is a useful measure, unless short survival reduces the time spent without active treatment, and in the case of a low likelihood of experiencing a net benefit in quality of life. Patients with reduced performance status (PS) may be especially at risk of futile treatment, despite having a relatively high symptom burden and thus a potential benefit. Therefore, we analyzed the symptom burden of patients with Eastern Cooperative Oncology Group (ECOG) PS 3-4 in our center.

PATIENTS AND METHODS

A retrospective study was performed of 102 consecutive patients who received palliative radiotherapy for different indications. The Edmonton Symptom Assessment Scale (ESAS) was employed to assess the pre-radiotherapy symptoms.

RESULTS

When applying the lowest threshold (ESAS ≥1), up to 97% of patients with PS 3-4 reported symptoms, such as fatigue and dry mouth. When focusing on moderate/severe symptoms (ESAS ≥4), still up to 77% of patients with PS 3-4 reported such a burden. The largest differences between patients with PS 3-4 and those with 0-1 were seen with regard to nausea, fatigue, dry mouth and reduced appetite. The median survival of patients with PS 3-4 was 2 months.

CONCLUSION

Given that many of the symptoms reported by patients with PS 3-4 tend to worsen temporarily after radiotherapy, patients with short survival may not experience a net benefit during the few weeks before death. However, if other symptoms such as dyspnea or pain prevail, short-course radiotherapy may result in worthwhile palliation and should, therefore, be considered on a case-by-case basis and after estimation of the remaining lifespan.

Stereotactic radiosurgery for brain metastases: A retrospective cohort study comparing treatment results between two lung cancer patient age groups, 75 years or older vs 65-74 years

BACKGROUND

There is little information on stereotactic radiosurgery (SRS) results for brain metastases (BMs) in lung cancer patients ≥75 years of age. We aimed to reappraise whether SRS results for patients ≥75 (very elderly) differ from those of patients with 65-74 years old (elderly).

METHODS

This IRB-approved retrospective cohort study was based on our prospectively-accumulated database including 7351 consecutive patients undergoing gamma knife (GK) SRS performed for BMs by two highly experienced neurosurgeons during the 1998-2018 period. We selected a total of 2915 elderly patients (age ≥65 years, 39.7 % of the 7351) with lung cancers (902 females, 2013 males, median age; 72 [maximum; 96] years, 2441 NSCLCs, 474 SCLCs) for this study.

RESULTS

Post-SRS median survival times (MSTs, months) differed significantly between the two lung cancer types, NSCLC (9.0) and SCLC (7.2, p < 0.0001). In NSCLC patients, post-SRS MSTs were significantly shorter in the very elderly (9.7) than those in the elderly (7.8) group (p < 0.0001). However, in SCLC patients, there were no significant MST differences (7.3 vs 6.9, p = 0.52) between the two age groups. In both NSCLC and SCLC patients, neither crude nor cumulative incidences of secondary endpoints in the very elderly group, i.e., neurological death, neurological deterioration, local recurrence, repeat SRS, salvage whole brain radiotherapy and SRS-related complications, were shown to be unfavorable to those in the elderly group.

CONCLUSIONS

Our results suggest that carefully-selected patients ≥75 years of age are not poor candidates for SRS as compared to those 65-74 years old.

LabBM Score and Extracranial Score As New Tools for Predicting Survival in Patients with Brain Metastases Treated with Focal Radiotherapy

Background Two recently validated, untraditional prognostic scores include serum albumin and lactate dehydrogenase, among other parameters. The latter are hemoglobin, platelet counts, and C-reactive protein (three-tiered LabBM score), whereas the four-tiered extracranial score includes more than one extracranial site of metastatic involvement. Until now, head-to-head comparisons of these two scores in patients treated with focal radiotherapy for newly diagnosed brain metastases are not available. Methods This was a retrospective single-institution analysis of 51 patients, most of whom were managed with first-line stereotactic radiosurgery (SRS). Survival was stratified by the LabBM score and extracranial score. Results Both scores predicted survival, but the analyses were hampered by small subgroups. In particular, very few patients belonged to the unfavorable groups. Survival shorter than two months, which was recorded in 14%, was not well predicted by the LabBM score and extracranial score. Conclusions Very few patients treated with focal radiotherapy (largely SRS) had unfavorable prognostic features according to the two untraditional scores, which do not include the number of brain metastases and performance status. Additional research is needed to improve the tools that predict short survival because overtreatment during the terminal phase of metastatic disease continues to represent a relevant issue.

External Validation of a Prognostic Score for Patients with Brain Metastases: Extended Diagnosis-Specific Graded Prognostic Assessment

PURPOSE

The aim of our study was the external validation of an extended variant of the four-tiered diagnosis-specific graded prognostic assessment (DS-GPA) that includes more information about extracranial disease burden and blood test results, and predicts survival of patients with brain metastases. The extracranial DS-GPA (EC-GPA) includes serum albumin, lactate dehydrogenase, and number of extracranial organs involved. Originally, the score was developed in Germany.

PATIENTS AND METHODS

A retrospective analysis of 236 patients with brain metastases treated with primary whole-brain radiotherapy in North-Norway was performed (independent external validation cohort).

RESULTS

The four-tiered EC-GPA score showed good discrimination between all prognostic groups (log-rank test p < 0.05 for all pairwise comparisons). One-year survival was 0, 11, 30, and 100%, respectively. Median survival was 0.7 months (95% CI, 0.5-0.9) in the worst prognostic group, with a hazard ratio for death of 44.31 (95% CI, 5.78-339.50) compared to the best group. In the German database, the corresponding HR was 31.64 (median survival 0.4 months). The remaining hazard ratios in this validation study were 7.13 and 12.10, compared with 4.84 and 9.26 in the score development study.

CONCLUSIONS

This study provides an independent validation of the EC-GPA, which was the best prognostic model for defining patients who did not benefit from radiation therapy of brain metastases in terms of overall survival in the original German study. The proposed modification of the established DS-GPA should undergo further validation in multi-institutional databases.

Long-term survival results after treatment for oligometastatic brain disease

Aim

The aim of this study was to characterize the survival results of patients with up to four brain metastases after intense local therapy (primary surgery or stereotactic radiotherapy) if extracranial metastases were absent or limited to one site, e.g. the lungs.

Background

Oligometastatic disease has repeatedly been reported to convey a favorable prognosis.

Material and methods

This retrospective study included 198 German and Norwegian patients treated with individualized approaches, always including brain radiotherapy. Information about age, extracranial spread, number of brain metastases, performance status and other variables was collected. Uni- and multivariate tests were performed.

Results

Median survival was 16.5 months (single brain metastasis) and 9.8 months (2-4, comparable survival for 2, 3 and 4), respectively (p = 0.001). After 5 years, 15 and 2% of the patients were still alive. In patients alive after 2 years, added median survival was 23 months and the probability of being alive 5 years after treatment was 26%. In multivariate analysis, extracranial metastases were not significantly associated with survival, while primary tumor control was.

Conclusion

Long-term survival beyond 5 years is possible in a minority of patients with oligometastatic brain disease, in particular those with a single brain metastasis. The presence of extracranial metastases to one site should not be regarded a barrier towards maximum brain-directed therapy.

Late Brain Oligometastases Diagnosed at Least 36 Months after Cancer Detection are Associated with Favorable Survival Outcome

Objective  The aim of this study was to investigate the impact of a long disease-free interval (at least 36 months from the first diagnosis of cancer) on survival in patients with brain oligometastases (maximum four lesions, no extracranial metastases). Methods This study involves a retrospective analysis in a group of 89 patients treated with different brain-directed approaches. Results We identified seven patients (8%) with an interval from cancer diagnosis to the development of brain metastases of at least 36 months. The median time interval was five months. The one-year survival rates were 80% (interval of at least 36 months) and 43% (shorter interval), respectively (p = 0.049). Correspondingly, a large difference in actuarial median survival was observed (39.9 months [95% confidence interval, 16.8-63.0 months] versus 9.7 months (95% confidence interval, 6.1-13.3 months). However, the two Kaplan-Meier curves were not statistically significantly different, p = 0.13. In addition to treatment-related differences, the two groups also differed with regard to the type of primary tumor (high versus low rates of non-small cell lung cancer) and gender. Conclusion Late dissemination was uncommon. The often applied strategy of effective local treatment for patients with brain-only oligometastases is warranted, especially if the disease-free interval had been at least 36 months. Larger studies are needed to fully understand the impact of confounding factors, such as gender and tumor biology.

External Validation of the LabBM Score in Patients With Brain Metastases

Background

The aim of this study was to validate the prognostic impact of the recently introduced three-tiered LabBM score in patients with brain metastases. In contrast to the previous development and validation cohorts, the present cohort did not include patients treated with primary surgery and/or radiosurgery. The score is based on hemoglobin, platelet counts, albumin, C-reactive protein and lactate dehydrogenase.

Methods

This was a retrospective single institution analysis. Overall, 167 patients managed with first-line whole-brain radiotherapy (WBRT) were identified from a prospectively maintained database.

Results

The LabBM score significantly predicted overall survival (median 4.0, 2.9 and 1.5 months, respectively).

Conclusions

The LabBM score is also valid in a patient population that differs from the previously studied cohorts, that is patients who were judged to be better candidates for WBRT than surgery or radiosurgery. As these patients in general represent a less favorable subset, their median survival was shorter than reported in the development cohort (11, 7 and 3 months, respectively). Future studies should examine whether or not combinations of the LabBM and other scores, for example, lung-molGPA and melanoma-molGPA, improve the clinical value of single scores.