Non-small Cell Lung Cancer Brain Metastases Research Articles

Immune checkpoint inhibitors for brain metastases in non-small-cell lung cancer: from rationale to clinical application.

Brain metastases (BM) is common in non-small-cell lung cancer (NSCLC) patients. Immune checkpoint inhibitors (ICIs)have gradually become a routine treatment for NSCLC BM patients. Currently, three PD-1 inhibitors (pembrolizumab, nivolumab and cemiplimab), one PD-L1 inhibitor (atezolizumab) and one CTLA-4 inhibitor (ipilimumab) have been approved for the first-line treatment of metastatic NSCLC. It is still controversial whether PD-L1, tumor infiltrating lymphocytes, and tumor mutation burden can be used as predictive biomarkers for immune checkpoint inhibitorsin NSCLC patients with BM. In addition, clinical data on NSCLC BM were inadequate. Here, we review the theoretical basis and clinical data for the application of ICIsin the therapy of NSCLC BM.

Abstract 2218: MET alterations are enriched in lung adenocarcinoma brain metastases and define a distinct molecular and transcriptomic subtype

Abstract Lung cancer has the highest incidence of metastases to the brain, with up to 40% of non-small cell lung cancer (NSCLC) patients developing brain metastases (BM). There is a critical need to develop novel treatments to effectively prevent and treat NSCLC BM. MET is a receptor tyrosine kinase that upon binding hepatocyte growth factor (HGF), mediates proliferation, epithelial-mesenchymal transition (EMT), invasion, angiogenesis and metastasis. Recent studies have suggested that the MET pathway may be a significant determinant of metastatic potential to the brain. We evaluated 125 lung adenocarcinoma (LUAD) BM and 477 primary LUAD for MET amplification (amp) by FISH (MET/CEP > 2) as well as other molecular alterations using targeted next-generation sequencing in a subset of LUAD BM (N=74) and primary LUAD (N=171) samples, including 13 paired primary and brain sets. We identified a significant enrichment of MET amp in LUAD BM (19%) compared to primary LUAD (3%; p<0.00001) or liver metastases (4%, N=80; p=0.002). High MET amp (MET/CEP7 ratio >5) was present in 6.5% of BM compared to 1.3% of primary LUAD cases (p=0.0006). In matched samples, BM-specific MET amp was observed. Non-exon 14 skipping MET activating mutations were also significantly more frequent in LUAD BM (22%) compared to primary LUAD (12%; p=0.05), as well as TP53, KRAS, SMAD4, APC, RB1, RET, ABL1, ALK, and VHL variants (adj. p values <0.02). VHL and IDH1 mutations were significantly increased in MET altered compared to non-MET altered BM. In addition, KRAS Q61X variants were more common in LUAD BM compared to LUAD and specifically more common in MET amp BM. We also examined MET activation in paired tumors using an HGF-MET proximity binding, dual-antibody assay. MET expression was increased in the majority of BM compared to the paired LUAD, and there were brain-specific MET activation was observed. RNASeq analysis identified distinct gene signatures in MET amplified (N=11) versus non-MET amplified (N=24) LUAD BM, including upregulation of the EMT and glycolytic pathways. We validated the importance of the EMT transcription factor, TWIST1 in MET-driven NSCLC tumorigenesis preclinically and confirmed activation of the glycolytic pathway in MET amplified NSCLC. Finally, non-invasive strategies to detect brain-specific MET alterations will be needed to identify BM patients who can benefit from MET inhibitors. Therefore, we examined 277 metastatic NSCLC patients that underwent standard of care circulating tumor DNA testing with the Guardant360 platform, and found that both MET mutation and/or amp were more frequently detected in LUAD patients with BM (p=0.04). Together, we show that over a third of LUAD BM patients have MET alterations compared to primary LUAD and may be responsive to MET inhibitors. Further, our liquid biopsy approach may allow us to identify BM-specific alterations for patient selection in clinical trials. Citation Format: Timothy F. Burns, Sanja Dacic, Maria A. Velez, Ashwin Somasundaram, Saveri Bhattacharya, Anish Chakka, Zachary A. Yochum, Jingxiao Jin, Ethan Miller, Brenda F. Kurland, Riyue Bao, Danielle P. Normolle, Sameer Agnihotri, Uma R. Chandran, Laura P. Stabile. MET alterations are enriched in lung adenocarcinoma brain metastases and define a distinct molecular and transcriptomic subtype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2218.

Mutation status and postresection survival of patients with non-small cell lung cancer brain metastasis: implications of biomarker-driven therapy.

Non-small cell lung cancer (NSCLC) is the most common primary tumor to develop brain metastasis. Prognostic markers are needed to better determine survival after neurosurgical resection of intracranial disease. Given the importance of mutation subtyping in determining systemic therapy and overall prognosis of NSCLC, the authors examined the prognostic value of mutation status for postresection survival of patients with NSCLC brain metastasis. The authors retrospectively analyzed all cases of NSCLC brain metastasis with available molecular testing data that were resected by a single surgeon at a single academic center from January 2009 to February 2019. Mutation status, demographic characteristics, clinical factors, and treatments were analyzed. Association between predictive variables and overall survival after neurosurgery was determined with Cox regression. Of the included patients (n = 84), 40% were male, 76% were smokers, the mean ± SD Karnofsky Performance Status was 85 ± 14, and the mean ± SD age at surgery was 63 ± 11 years. In total, 23%, 26%, and 4% of patients had EGFR, KRAS, and ALK/ROS1 alterations, respectively. On multivariate analysis, survival of patients with EGFR (HR 0.495, p = 0.0672) and KRAS (HR 1.380, p = 0.3617) mutations were not significantly different from survival of patients with wild-type (WT) tumor. However, the subgroup of patients with EGFR mutation who also received tyrosine kinase inhibitor (TKI) therapy had significantly prolonged survival (HR 0.421, p = 0.0471). In addition, postoperative stereotactic radiosurgery (HR 0.409, p = 0.0177) and resected tumor diameter < 3 cm (HR 0.431, p = 0.0146) were also significantly associated with prolonged survival, but Graded Prognostic Assessment score ≤ 1.0 (HR 2.269, p = 0.0364) was significantly associated with shortened survival. Patients with EGFR mutation who receive TKI therapy may have better survival after resection of brain metastasis than patients with WT tumor. These results may inform counseling and decision-making regarding the appropriateness of resection of NSCLC brain metastasis.

Fully Automated MR Detection and Segmentation of Brain Metastases in Non-small Cell Lung Cancer Using Deep Learning.

Non-small cell lung cancer (NSCLC) is the most common tumor entity spreading to the brain and up to 50% of patients develop brain metastases (BMs). Detection of BMs on MRI is challenging with an inherent risk of missed diagnosis. To train and evaluate a deep learning model (DLM) for fully automated detection and 3D segmentation of BMs in NSCLC on clinical routine MRI. Retrospective. Ninety-eight NSCLC patients with 315 BMs on pretreatment MRI, divided into training (66 patients, 248 BMs) and independent test (17 patients, 67 BMs) and control (15 patients, 0 BMs) cohorts. T1 -/T2 -weighted, T1 -weighted contrast-enhanced (T1 CE; gradient-echo and spin-echo sequences), and FLAIR at 1.0, 1.5, and 3.0 T from various vendors and study centers. A 3D convolutional neural network (DeepMedic) was trained on the training cohort using 5-fold cross-validation and evaluated on the independent test and control sets. Three-dimensional voxel-wise manual segmentations of BMs by a neurosurgeon and a radiologist on T1 CE served as the reference standard. Sensitivity (recall) and false positive (FP) findings per scan, dice similarity coefficient (DSC) to compare the spatial overlap between manual and automated segmentations, Pearson's correlation coefficient (r) to evaluate the relationship between quantitative volumetric measurements of segmentations, and Wilcoxon rank-sum test to compare the volumes of BMs. A P value <0.05 was considered statistically significant. In the test set, the DLM detected 57 of the 67 BMs (mean volume: 0.99 ± 4.24 cm3 ), resulting in a sensitivity of 85.1%, while FP findings of 1.5 per scan were observed. Missed BMs had a significantly smaller volume (0.05 ± 0.04 cm3 ) than detected BMs (0.96 ± 2.4 cm3 ). Compared with the reference standard, automated segmentations achieved a median DSC of 0.72 and a good volumetric correlation (r= 0.95). In the control set, 1.8 FPs/scan were observed. Deep learning provided a high detection sensitivity and good segmentation performance for BMs in NSCLC on heterogeneous scanner data while yielding a low number of FP findings. Level of Evidence 3 Technical Efficacy Stage 2.

A prospective data analysis of targeted therapy combined with concurrent radiation therapy for brain metastasis from NSCLC with driver gene mutation.

e14006 Background: Previous studies have shown that brain metastases of non-small cell lung cancer (NSCLC) with positive driver genes have poor prognosis. There is still lack of prospective studies on the efficacy and safety of targeted therapy combined with concurrent radiotherapy for brain metastases(BM). Methods: NSCLC patients, with ECOG score 0-2, having MRI confirmed brain or meningeal metastases were eligible. Patients must have driver gene mutation and received corresponding targeted therapy. The intracranial radiotherapy regimen was SRS or whole brain radiotherapy. The primary objective was iPFS (intracranial progression-free survival); Secondary objectives were: iORR (intracranial objective response rate), PFS (progression-free survival), OS (overall survival). MMSE (Mini Mental State Examination) and FACT-Br was carried out before/after weekly radiotherapy and during systematic treatment. Treatment-related toxicities were assessed according RTOG/EORTC criteria. Tumor responses were evaluated using RECIST V1.1 criteria. Survival analysis was performed using the Graphprism version 6.0 by Kaplan-Meier method and log-rank test. Results: 23 NSCLC with BM was included. Among them, 10 patients were newly diagnosed with NSCLC BM. 2 patients’ BM progressed after targeted therapy. 11 NSCLC patients were newly diagnosed with BM after targeted therapy. 91.3% of patients presented an EGFR mutation, including primarily EGFR 19-exon deletion, EGFR 21-L8585R. 11.5% presented with c-MET mutation. Median age was 58.34 yrs(44-71yrs). Patients were mostly treated with Erolotinib and Gefitinib. All patients were adenocarcinoma. At last follow-up, for patients newly diagnosed with NSCLC BM, 8 patients had achieved intracranial progression, and 7 patients had reached OS, of which 1 died before completing WBRT. The median iPFS was 9.3m(95%CI:0.571-4.055) and the median OS was 11.9m (95%CI:0.2752 -2.732). As for patients who progressed after targeted therapy, one patient’s OS was 4.4m, iPFS of the other patient was 3.9m. Among NSCLC patients who were newly diagnosed with BM after targeted therapy, 8 patients had achieved intracranial progression and 5 patients had reached OS. The median iPFS was 6.13m (95%CI:0.247-1.751) and the mOS was 13.8m (95%CI:0.3660-3.634). Common adverse effects include dry skin, fatigue, dizziness, headache, anorexia, and grade I myelosuppression and no serious adverse events (SAEs); MMSE and FACT-Br scores were no significant differences at baseline and follow-up. Conclusions: In stage IV brain metastatic NSCLC with driver gene mutation, targeted therapy combined with concurrent radiotherapy for BM is tolerable, and there is no significant impact on the quality of life and cognitive function after radiotherapy. The evaluation of efficacy requires further follow-up. Support:LC2019ZD009,81972853 and 81572279.

Outcomes of first, second, and third-generation anaplastic lymphoma kinase (ALK) inhibitors in non-small cell lung cancer brain metastases (NSCLCBM).

2034 Background: Non-small cell lung cancer (NSCLC) is the most common cause of brain metastases. ALK, which codes for tyrosine kinase receptors, is rearranged in 4-7% of NSCLC. First-generation ALK inhibitors have restricted efficacy due to poor blood-brain barrier (BBB) penetration and ALK-resistant tumor mutations. Second-generation ALK inhibitors have shown better BBB penetration, while third-generation ALK inhibitors were efficacious even against ALK-resistant mutations. In this retrospective study, we investigated the overall survival (OS) and progression-free survival (PFS) in NSCLCBM patients treated with first, second, and third-generation ALK inhibitors. Methods: NSCLCBM patients between 2010 and 2019 were evaluated. We analyzed data regarding molecular marker status, systemic therapies, and date of progression. OS was defined as the start date of systemic therapy to the date of last follow-up or death. The Cox proportional model was used to estimate OS and PFS. Results: A total of 90 patients had ALK gene rearrangement. 16 ALK positive patients received first-generation ALK inhibitor (crizotinib), with a median age of 59.2 years, 50% of the cohort being female and 83.3% being white. Another 17 patients received second-generation (alectinib, ceritinib, brigatinib) and third-generation ALK inhibitors (lorlatinib), with a combined median age of 52.2 years and a cohort of 52.6% females and 72.2% white patients. The 5-year OS rate was 49% (95% confidence interval (CI) = 24%, 71%) for first-generation ALK inhibitors and 76% (95% CI = 40%, 92%) for second and third-generation ALK inhibitors (p-value (p) = 0.019). The median PFS (mPFS) for patients who received first-generation ALK inhibitors was 45.3 months and for those who received second or third-generation ALK inhibitors was 180.1 months. The respective 5-year PFS rate was 43% (95% CI = 19%, 65%) and 72% (95% CI = 42%, 89%). Conclusions: Newer generations of targeted therapies in NSCLCBM have improved BBB penetration and effectiveness against resistant mutations. We determined that there was a significant 5-year OS benefit in patients who received second and third-generation ALK inhibitors compared to first-generation ALK inhibitors, and a respective trend towards significant PFS benefit in newer-generation ALK inhibitors when compared to first-generation. These results are encouraging, but the effect on intracranial lesion size and response rates should be examined in the future.[Table: see text]

Combination of Immune Checkpoint Inhibitors and Anti-Angiogenic Agents in Brain Metastases From Non-Small Cell Lung Cancer.

Brain metastases remain a critical issue in the management of non-small cell lung cancer (NSCLC) because of the high frequency and poor prognosis, with survival rates often measured in just months. The local treatment approach remains the current standard of care, but management of multiple asymptomatic brain metastases always involves systemic therapy. Given that anti-angiogenic agents and immune checkpoint inhibitors (ICIs) both target the tumor microenvironment (TME), this combination therapy has become a promising strategy in clinical practice. Increasing number of preclinical and clinical studies have shown remarkable anti-tumor activity of the combination therapy, but the efficacy in brain metastases is unclear due to the strict selection criteria adopted in most clinical trials. This review briefly summarizes the potential synergistic anti-tumor effect and clinical development of the combination of anti-angiogenic agents and ICIs in NSCLC brain metastases, and discusses the existing challenges and problems.

Efficacy and Safety of Anlotinib in Patients with Advanced Non-Small Cell Lung Cancer: A Real-World Study.

BackgroundAnlotinib is a multi-target tyrosine kinase inhibitor (TKI) independently developed by China, which can inhibit tumor angiogenesis and tumor cell proliferation. The ALTER 0303 study has suggested that anlotinib improved overall survival (OS) and progression-free survival (PFS) in the treatment of advanced non-small cell lung cancer (NSCLC). However, in the real world, the efficacy and safety of anlotinib is not clear. Although relevant retrospective studies have confirmed the efficacy and safety of anlotinib, the sample size is small. And the OS was not observed because of the follow-up time was short. Further studies are still essential to evaluate the efficacy and safety of anlotinib in patients with advanced NSCLC in real-world settings. Related studies have preliminarily shown that anlotinib combined with whole-brain radiotherapy (WBRT) can significantly prolong the survival of patients with brain metastases of NSCLC. This study also discusses the best treatment strategies of patients with brain metastases.MethodsA retrospective study was conducted on 206 patients with advanced NSCLC who had treated with anlotinib. The primary endpoints were PFS and OS. The secondary endpoints were objective response rate (ORR), disease control rate (DCR) and safety. Kaplan–Meier survival curves were applied to evaluate the efficacy. Univariate analysis was performed by Log rank testing. Cox regression analysis was utilized to evaluate the significance of potential risk factors obtained from the univariate analysis.ResultsThe median PFS (mPFS) was 4.0 (95% CI: 3.607–4.393) months, univariate analysis revealed that patients with longer PFS included epidermal growth factor receptor (EGFR) mutation-negative, Eastern Cooperative Oncology Group performance status (ECOG PS) ≤1, no brain metastases, no liver metastases, no adrenal metastases, or ≤2 distant metastases. Cox regression analysis indicated that patients with EGFR-negative and ECOG PS ≤1 had longer PFS. The median OS (mOS) was 8(95% CI: 6.495–9.505) months. EGFR mutation-negative, previous thoracic radiation therapy, no brain metastases, or ≤2 distant metastases were independent positive predictors of OS. The results of Cox regression indicated that the patients without previous thoracic radiation therapy (hazard ratio: 1.855; 95% CI: 1.162-2.960; p=0.010) had shortened OS. The objective response rate was 10.2%, and the disease control rate was 78.2%. The main treatment-related adverse events (AEs) were generally tolerated. All AEs observed during the trial were controlled after dose reduction or symptomatic treatments, and no death was found to be associated with anlotinib.ConclusionAnlotinib was well tolerated and effective in patients with advanced NSCLC. Patients with EGFR mutation-negative and ECOG PS ≤1 had longer PFS, and patients without previous thoracic radiation therapy (HR: 1.855, 95% CI 1.162–2.960; P = 0.010) had shorter OS. Further investigations are needed because of small sample.

Challenges and Novel Opportunities of Radiation Therapy for Brain Metastases in Non-Small Cell Lung Cancer.

Approximately 20% patients with non-small cell lung cancer (NSCLC) present with CNS spread at the time of diagnosis and 25-50% are found to have brain metastases (BMs) during the course of the disease. The improvement in the diagnostic tools and screening, as well as the use of new systemic therapies have contributed to a more precise diagnosis and prolonged survival of lung cancer patients with more time for BMs development. In the past, most of the systemic therapies failed intracranially because of the inability to effectively cross the blood brain barrier. Some of the new targeted therapies, especially the group of tyrosine kinase inhibitors (TKIs) have shown durable CNS response. However, the use of ionizing radiation remains vital in the management of metastatic brain disease. Although a decrease in CNS-related deaths has been achieved over the past decade, many challenges arise from the need of multiple and repeated brain radiation treatments, which carry along not insignificant risks and toxicity. The combination of stereotactic radiotherapy and systemic treatments in terms of effectiveness and adverse effects, such as radionecrosis, remains a subject of ongoing investigation. This review discusses the challenges of the use of radiation therapy in NSCLC BMs in view of different systemic treatments such as chemotherapy, TKIs and immunotherapy. It also outlines the future perspectives and strategies for personalized BMs management.

Neutrophil-to-Lymphocyte Ratio Is Superior to Other Leukocyte-Based Ratios as a Prognostic Predictor in Non–Small Cell Lung Cancer Patients with Radiosurgically Treated Brain Metastases Under Immunotherapy or Targeted Therapy

To investigate predictive value of preradiosurgery leukocyte-based prognostic ratios in a selected cohort of non-small cell lung cancer (NSCLC) patients with radiosurgery-treated brain metastases (BM) and concomitant immunotherapy (IT) or targeted therapy (TT). We performed a retrospective analysis of 166 patients with NSCLC BM treated with Gamma Knife radiosurgery. Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, and lymphocyte-to-monocyte ratio were assessed within 14 days before radiosurgery. In radiosurgically treated patients with NSCLC BM with concomitant IT or TT, estimated median survival after first Gamma Knife radiosurgery treatment was significantly longer in patients with NLR cutoff value <5 (P= 0.038). Consequently, the Cox regression model for NLR cutoff value groups revealed a significant hazard ratio of 1.519 (95% confidence interval 1.020-2.265, P= 0.040). In addition, each increase in NLR of 1 equaled an increase of 5.4% in risk of death (hazard ratio 1.054, 95% confidence interval 1.024-1.085, P < 0.001). After adjusting for sex, age, Karnofsky performance scale, and presence of extracranial metastases, NLR remained a significant and independent predictor for survival (hazard ratio 1.047, 95% confidence interval 1.017-1.078, P= 0.002). In contrast, platelet-to-lymphocyte ratio and lymphocyte-to-monocyte ratio did not exhibit the same predictive value among patients with radiosurgery-treated BM with concomitant IT or TT. In patients with NSCLC BM treated with radiosurgery with concomitant IT or TT, preradiosurgery NLR represents a simple prognostic predictor for survival and is superior to other leukocyte-based ratios. NLR may be relevant for clinical decision making, therapeutic evaluation, patient counseling, and appropriate stratification of future clinical trials among patients with radiosurgery-treated BM.

Differentiation of brain metastases from small and non-small lung cancers using apparent diffusion coefficient (ADC) maps

BackgroundBrain metastases are particularly common in patients with small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), with NSCLC showing a less aggressive clinical course and lower chemo- and radio sensitivity compared to SCLC. Early adequate therapy is highly desirable and depends on a reliable classification of tumor type. The apparent diffusion coefficient is a noninvasive neuroimaging marker with the potential to differentiate between major histological subtypes. Here we determine the sensitivity and specificity of the apparent diffusion coefficient to distinguish between NSCLC and SCLC.MethodsWe enrolled all NSCLC and SCLC patients diagnosed between 2008 and 2019 at the University Medical Center Göttingen. Cranial MR scans were visually inspected for brain metastases and the ratio of the apparent diffusion coefficient (ADC) was calculated by dividing the ADC measured within the solid part of a metastasis by a reference ADC extracted from an equivalent region in unaffected tissue on the contralateral hemisphere.ResultsOut of 411 enrolled patients, we detected 129 patients (83 NSCLC, 46 SCLC) with sufficiently large brain metastases with histologically classified lung cancer and no hemorrhage. We analyzed 185 brain metastases, 84 of SCLC and 101 of NSCLC. SCLC brain metastases showed an ADC ratio of 0.68 ± 0.12 SD, and NSCLC brain metastases showed an ADC ratio of 1.47 ± 0.31 SD. Receiver operating curve statistics differentiated brain metastases of NSCLC from SCLC with an area under the curve of 0.99 and a 95% CI of 0.98 to 1, p < 0.001. Youden's J cut-point is 0.97 at a sensitivity of 0.989 and a specificity of 0.988.ConclusionsIn patients with lung cancer and brain metastases with solid tumor parts, ADC ratio enables an ad hoc differentiation of SCLC and NSCLC, easily achieved during routine neuroradiological examination. Non-invasive MR imaging enables an early-individualized management of brain metastases from lung cancer.Trial registration: The study was registered in the German Clinical Trials Register (DRKS00023016).

Abstract PO-041: An immunologic niche of antigen presenting cells and stem-like CD8+ T-cells is present in non-small cell lung cancer brain metastases

Abstract Background: Non-small cell lung cancer (NSCLC) patients with brain metastases have a very poor prognosis. The first line treatments for NSCLC brain metastases are typically surgery and pre- or post-operative stereotactic radiosurgery (SRS) or SRS alone. However, subsequent intra-cranial failure and death is common. Importantly, we have previously shown that a unique immune niche in genitourinary malignancies correlates with the risk for disease recurrence. Accordingly, here we investigated whether this immune niche was present in brain metastases, whether it correlated with patient outcomes, and whether it was modulated by SRS. Methods: Formalin fixed paraffin embedded brain metastases were stained by immunofluorescence for CD8, PD-1, TCF-1, MHC-II and DAPI. Following successful image acquisition using fluorescent whole slide scanning, we used a custom quantitative analysis pipeline to measure the cellularity, relative cellular locations, local cellular density, and marker staining intensity. Results: We identified immune niches consisting of both stem-like TCF-1+ CD8+ T-cells and antigen presenting cells (MHC-II+) in brain metastases. TCF-1+ CD8+ T-cells were found at in areas of higher MHC-II+ cell density than the TCF-1 CD8+negative T-cells. The amount of tumor issue occupied by immune niches correlated with TCF1+ CD8+ T-cell infiltration, as well as with total CD8+ T-cell and MHC-II+ cell infiltration. Importantly, we found that higher MHC-II+ cell density correlated with longer overall survival in this cohort of patients. Additionally, we found this immune niche is preserved following pre-operative SRS. Conclusions: Our study is the first to demonstrate stem-like CD8+ T-cells in brain metastases and that these cells form an immune niche similar to those described extra-cranial tumor sites. Additionally, we report that the immune niche is preserved following SRS, which is highly clinically relevant to the use of combinatorial strategies between SRS and checkpoint blockade. Citation Format: Caroline S. Jansen, Luke del Balzo, Roshan Prabhu, Suzanna Logan, Prasanthi Chappa, Kirtesh Patel, Scott Wilkinson, Ross Lake, Hui-Kuo G. Shu, Jim Zhong, Vishal Dhere, Jeffrey Olson, Adam G. Sowalsky, Mohammad K. Khan, Haydn T. Kissick, Zachary S. Buchwald. An immunologic niche of antigen presenting cells and stem-like CD8+ T-cells is present in non-small cell lung cancer brain metastases [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PO-041.

Neutrophil to lymphocyte ratio influences impact of steroids on efficacy of immune checkpoint inhibitors in lung cancer brain metastases

Steroids are often utilized to manage patients with non-small cell lung cancer brain metastases (NSCLCBM). Steroids and elevated neutrophil-to-lymphocyte ratio (NLR) have been associated with decreased overall survival (OS) in patients treated with immune checkpoint inhibitors (ICI). We retrospectively investigated patients treated with ICI after the diagnosis of NSCLCBM at a single tertiary care institution examing the impact of steroids and NLR. Overall survival (OS) and intracranial progression-free survival (PFS) were analyzed. 171 patients treated with ICI for NSCLCBM were included. Thirty-six received steroids within 30 days of the start of ICI, and 53 patients had an NLR ≥ 5 before the start of ICI. Upfront steroids was associated with decreased OS on multivariable analysis (median OS 10.5 vs. 17.9 months, p = .03) and intracranial PFS (5.0 vs. 8.7 months, p = .045). NLR ≥ 5 was indicative of worse OS (10.5 vs. 18.4 months, p = .04) but not intracranial PFS (7.2 vs. 7.7 months, p = .61). When NLR and upfront steroids are modeled together, there is a strong interaction (p = .0008) indicating that the impact of steroids depended on the patient’s NLR. In a subgroup analysis, only in patients with NLR < 4 was there a significant difference in OS with upfront steroids (26.1 vs. 15.6 months, p = .032). The impact of steroids on the efficacy of ICI in patients with NSCLCBM is dependent on the patient's NLR underscoring its importance in these patients. Patients with a low NLR, steroid use decreases the efficacy of ICI. These results can inform clinicians about the impact of steroids in patients treated with ICI.

Upfront pembrolizumab as an effective treatment start in patients with PD-L1 ≥ 50% non-oncogene addicted non-small cell lung cancer and asymptomatic brain metastases: an exploratory analysis.

The efficacy of immune checkpoint inhibitors in patients with brain metastases (BMs) from non-oncogene addicted non-small cell lung cancer (NSCLC) is under investigation. Here, we sought to determine the optimal management of NSCLCs with PD-L1 ≥ 50% and asymptomatic BMs who were treated with first-line pembrolizumab. Thirty patients from 15 institutions with PD-L1 ≥ 50% NSCLC had asymptomatic BMs, and met inclusion criteria. Patients were classified based on whether they had undergone upfront local radiotherapy for BMs as well as on the type of brain radiotherapy received. Nine patients were treated with upfront pembrolizumab alone, 8 patients with whole-brain radiotherapy (WBRT) followed by pembrolizumab and 13 patients with stereotactic radiosurgery (SRS) followed by pembrolizumab. Patients' characteristics were similar among the three groups of patients except for a higher number of BMs ≥ 3 in the WBRT group. One complete and 4 partial intracranial responses were observed with upfront pembrolizumab alone. The median survival was not reached for the pembrolizumab and WBRT (n = 8) groups, and it was 7.6months for the SRS (n = 13) group (P = 0.09), with 12-month survival rates being 55.5%, 62.5%, and 23.0%, respectively. Salvage WBRT was delivered in 1 patient in the upfront pembrolizumab group and in 4 patients in the SRS group. Upfront pembrolizumab showed efficacy in selected patients with PD-L1 ≥ 50% non-oncogene addicted NSCLC and asymptomatic BMs. Prospective studies should address whether pembrolizumab alone, and deferral of radiotherapy, could be pursued in this patient population.

Risk factors for brain metastases from non-small-cell lung cancer: A protocol for observational study.

Brain metastasis is a common site of distant metastasis of non-small-cell lung cancer (NSCLC) that greatly reduces the prognosis of patients. In this study, we explored the correlation between different clinical factors and secondary brain metastases in NSCLC in an attempt to identify NSCLC patient populations at high risk of metastasis to the central nervous system.We collected data for 350 NSCLC patients from the medical record system of the First Affiliated Hospital of Nanchang University from June 2015 to June 2019, and these patients had pathologically verified diagnoses. The correlations between age at the time of diagnosis, sex, histological type, calcium concentration, hemoglobin (HB), fibrinogen (Fbg), activated partial thromboplastin time (APTT), alkaline phosphatase (ALP), carcinoembryonic antigen (CEA), CA125, and CA199 levels and brain metastasis were analyzed. Multivariate logistic regression analysis was used to identify risk factors for NSCLC brain metastasis. A receiver operating characteristic (ROC) curve was used to calculate the cutoff, sensitivity, and specificity of the independent related factors.Of the 350 patients, 57 were diagnosed with brain metastases. Univariate and multivariate logistic regression analysis indicated that lesion diameter, calcium concentration, and CEA level were independent risk factors correlated with brain metastasis (P < .05). There were no significant differences in age, sex, type of histopathology, presence or absence of mediastinal lymph node metastasis, HB, Fbg, APTT, ALP, cancer antigen 125 (CA-125), or cancer antigen 199 (CA-199) levels between patients with brain metastases and patients without brain metastases (P > .05, respectively). ROC curves demonstrated that these factors had comparable accuracy in predicting brain metastasis (area under the curve [AUCs] were 0.620, 0.661, and 0.729, respectively). The cutoff values for lesion diameter, calcium, and CEA were 5.050 cm, 2.295 mmol/L, and 11.160 ng/mL, respectively. The sensitivities for prediction brain metastasis were 59.6%, 64.9%, and 73.3%, with specificities of 63.1%, 59.2%, and 70.3%, respectively.According to our study, lesion diameter, calcium concentration, and CEA level are independent risk factors for brain metastases in NSCLC patients. Thus, we can strengthen the regular follow-up of NSCLC patients with tumor diameter > 5.050 cm, calcium > 2.295 mmol/L, CEA > 11.160 ng/mL, and use these factors as a reference for preventive treatments.

FP07.01 Dysbiosis of Gut Microbiota Suppress the Brain Metastasis of Non-Small Cell Lung Cancer

Brain metastasis (BM) is associated with poor prognosis in patients with advanced non-small cell lung cancer (NSCLC), gut microbiota have been reported involved in the development of NSCLC. However, the impact of the gut microbiota on BM of NSCLC is still vague to date. This study aimed to explore the potential mechanism of gut microbiota dysbiosis on BM of NSCLC.

Anti-PD-(L)1 immunotherapy for brain metastases in non-small cell lung cancer: Mechanisms, advances, and challenges.

The brain is one of the most common metastatic sites in non-small cell lung cancer (NSCLC), which is associated with an extremely poor prognosis. Despite the availability of several therapeutic options, the treatment efficacy remains unsatisfactory for NSCLC brain metastases. Anti-programmed cell death-1 (PD-1) and its ligand (PD-L1) monoclonal antibodies have reshaped therapeutic strategies in advanced NSCLC. Preliminary evidence has shown that anti-PD-(L)1 monotherapy is also effective in NSCLC patients with brain metastases. However, the traditional view asserted that these therapeutic antibodies were incapable of crossing the blood-brain barrier (BBB) with large molecular size, thus most patients with brain metastases were excluded from most studies on anti-PD-(L)1 immunotherapy. Therefore, the efficacy and its mechanisms of action of anti-PD-(L)1 immunotherapy against brain metastases in NSCLC have not been clarified. In this review, we will survey the underlying mechanisms and current clinical advances of anti-PD-(L)1 immunotherapy in the treatment of brain metastases in NSCLC. The trafficking of activated cytotoxic T cells that are mainly derived from the primary tumor and deep cervical lymph nodes is critical for the intracranial response to anti-PD-(L)1 immunotherapy, which is driven by interferon-γ (IFN-γ). Additionally, promising combined strategies with the rationale in the treatment of brain metastases will be presented to provide future directions for clinical study design. Several significant challenges in the preclinical and clinical studies of brain metastases, as well as potential solutions, will also be discussed.

Improved survival and disease control following pembrolizumab-induced immune-related adverse events in high PD-L1 expressing non-small cell lung cancer with brain metastases.

Immune checkpoint inhibitors have become standard of care for many patients with non-small cell lung cancer (NSCLC). These agents often cause immune-related adverse events (IRAEs), which have been associated with increased overall survival (OS). Intracranial disease control and OS for patients experiencing IRAEs with metastatic NSCLC and brain metastases have not yet been described. We performed a single-institution, retrospective review of patients with NSCLC and existing diagnosis of brain metastasis, who underwent pembrolizumab treatment and developed any grade IRAE. The primary outcome of the study was intracranial time to treatment failure (TTF), defined from time of pembrolizumab initiation to new intracranial disease progression or death. Kaplan-Meier and Cox proportional hazard analyses were performed. A total of 63 patients with NSCLC brain metastasis were identified, and 24 developed IRAEs. Patients with any grade IRAEs had longer OS (21 vs. 10months, p = 0.004), systemic TTF (15 vs. 4months, p < 0.001) and intracranial TTF (14 vs. 5months, p = 0.001), relative to patients without IRAEs. Presence of IRAEs and high PD-L1 (≥ 50%), but not absent/moderate PD-L1 (0-49%), had a positive association for OS, systemic TTF, and intracranial TTF. Following multivariable analysis, IRAE experienced on pembrolizumab was an independent predictor of OS, systemic TTF, and intracranial TTF. In our series of patients with NSCLC and brain metastases treated with pembrolizumab, IRAE presence was associated with a significant increase in OS, systemic TTF, and intracranial TTF. Future studies with increased cohorts will clarify how IRAEs should be interpreted among molecular subtypes.

Differentiating Small-Cell Lung Cancer From Non-Small-Cell Lung Cancer Brain Metastases Based on MRI Using Efficientnet and Transfer Learning Approach.

Differentiation between small-cell lung cancer (SCLC) from non-small-cell lung cancer (NSCLC) brain metastases is crucial due to the different clinical behaviors of the two tumor types. We propose the use of a deep learning and transfer learning approach based on conventional magnetic resonance imaging (MRI) for non-invasive classification of SCLC vs. NSCLC brain metastases. Sixty-nine patients with brain metastasis of lung cancer origin were included. Of them, 44 patients had NSCLC and 25 patients had SCLC. Classification was performed with EfficientNet architecture on crop images of lesion areas and based on post-contrast T1-weighted, T2-weighted and FLAIR imaging input data. Evaluation of the model was carried out in a 5-fold cross-validation manner, and based on accuracy, precision, recall, F1 score and area under the receiver operating characteristic curve. The best classification results were obtained with multiparametric MRI input data (T1WI+c+FLAIR+T2WI), with a mean overall accuracy of 0.90 ± 0.04, and F1 score of 0.92 ± 0.05 for NSCLC and 0.87 ± 0.08 for SCLC for the validation data and an accuracy of 0.87 ± 0.05, with an F1 score of 0.88 ± 0.05 for NSCLC and 0.85 ± 0.05 for SCLC for the test dataset. The proposed method provides an automatic noninvasive method for the classification of brain metastasis with high sensitivity and specificity for differentiation between NSCLC vs. SCLC brain metastases. It may be used as a diagnostic tool for improving decision-making in the treatment of patients with these metastases. Further studies on larger patient samples are required to validate the current results.

Research Progress in the Treatment of Brain Metastases from Non-small Cell Lung Cancer

肺癌是全世界癌症相关死亡的首要原因，肺癌最常见的病理类型是非小细胞肺癌（non-small cell lung cancer, NSCLC），NSCLC引起的脑转移发病率一直呈上升趋势。脑转移严重影响患者的认知功能、生存时间及生活质量，预后极差，自然病程约1个月-3个月。经过治疗后中位生存时间也仅有3个月-6个月，1年生存率为14%，2年生存率仅为7.6%。脑转移的部位、数量、大小与其症状及生存期相关，有中枢神经系统症状的患者预后更差。脑转移瘤治疗的目标是优化总体生存率和生活质量，并优先保留神经认知功能。目前，NSCLC脑转移的主要治疗方式包括放疗、手术、化疗、分子靶向、免疫治疗。临床上要根据患者的异质性（临床特点、病理类型、组织分型等），对患者最佳的治疗方式进行多学科的评估。本文旨在对当前治疗方法的研究进展进行综述。