Multiple treatment modalities for brain metastasis in patients with EGFR-mutant non-small-cell lung cancer

Modern Stereotactic Radiotherapy for Brain Metastases from Lung Cancer: Current Trends and Future Perspectives Based on Integrated Translational Approaches

Brain metastases (BMs) represent the most frequent metastatic event in the course of lung cancer patients, occurring in approximately 50% of patients with non-small-cell lung cancer (NSCLC) and in up to 70% in patients with small-cell lung cancer (SCLC). Thus far, many advances have been made in the diagnostic and therapeutic procedures, allowing improvements in the prognosis of these patients. The modern approach relies on the integration of several factors, such as accurate histological and molecular profiling, comprehensive assessment of clinical parameters and precise definition of the extent of intracranial and extracranial disease involvement. The combination of these factors is pivotal to guide the multidisciplinary discussion and to offer the most appropriate treatment to these patients based on a personalized approach. Focal radiotherapy (RT), in all its modalities (radiosurgery (SRS), fractionated stereotactic radiotherapy (SRT), adjuvant stereotactic radiotherapy (aSRT)), is the cornerstone of BM management, either alone or in combination with surgery and systemic therapies. We review the modern therapeutic strategies available to treat lung cancer patients with brain involvement. This includes an accurate review of the different technical solutions which can be exploited to provide a "state-of-art" focal RT and also a detailed description of the systemic agents available as effective alternatives to SRS/SRT when a targetable molecular driver is present. In addition to the validated treatment options, we also discuss the future perspective for focal RT, based on emerging clinical reports (e.g., SRS for patients with many BMs from NSCLC or SRS for BMs from SCLC), together with a presentation of innovative and promising findings in translational research and the combination of novel targeted agents with SRS/SRT.

The Efficacy and Safety of Afatinib in Non-Small Cell Lung Cancer Patients with Brain Metastasis: A Meta-Analysis

Aim

The aim of this study is to evaluate the efficacy and safety of afatinib in the treatment of non-small cell lung cancer (NSCLC) patients with brain metastasis based on meta-analysis.

Methods

Related literatures were searched in the following databases: EMbase, PubMed, China Knowledge Network (CNKI), Wanfang, Weipu, Google Scholar, the China Biomedical Literature Service System, and other databases. Clinical trials and observational studies that met the requirements were selected for meta-analysis using Revman 5.3. The hazard ratio (HR) was used as an indicator of the impact of afatinib.

Results

A total of 142 related literatures were acquired, but after screening, five literatures were selected for data extraction. The following indices were compared: the progression-free survival (PFS), overall survival (OS), and common adverse reactions (ARs) of grade 3 and above. A total of 448 patients with brain metastases were included and were divided into two groups: the control group (no afatinib treatment, with chemotherapy alone and the first-generation EGFR-TKIs) and the afatinib group. The results showed that afatinib could improve PFS (HR: 0.58, 95% CI: 0.39-0.85, P < 0.05) and ORR (OR = 2.86, 95% CI: 1.45-2.57, P < 0.05), but had no benefit on OS (HR: 1.13, 95% CI: 0.15-8.75, P > 0.05) and DCR (OR = 2.87, 95% CI: 0.97-8.48, P > 0.05). For the safety of afatinib, the incidence of grade-3-and-above ARs was low (HR: 0.01, 95% CI: 0.00-0.02, P < 0.05).

Conclusion

Afatinib improves the survival of NSCLC patients with brain metastases and shows satisfactory safety.

Long non-coding RNA MCM3AP antisense RNA 1 promotes non-small cell lung cancer progression through targeting microRNA-195-5p

Lung cancer (LC) ranks first among all causes of cancer-related death, with non-small cell lung cancer (NSCLC) taking up 85% of lung cancer cases. Although lncRNA MCM3AP antisense RNA 1 (MCM3AP-AS1) has been reported to be an oncogenic factor in NSCLC, its detailed mechanism in NSCLC is unknown. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine MCM3AP-AS1, microRNA (miR)-195-5p and E2F transcription factor 3 (E2F3) mRNA expressions in NSCLC tissues and cells. Western blot was utilized to determine the expression levels of E2F3, BCL2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2), E-cadherin and N-cadherin. CCK-8 and Transwell assays were conducted to examine cell proliferation, migration and invasion, respectively. Dual-luciferase reporter assay and RNA immunoprecipitation experiments were used to determine the regulatory relationships between MCM3AP-AS1 and miR-195-5p, and miR-195-5p and E2F3. We demonstrated that MCM3AP-AS1 was overexpressed in NSCLC tissues and cells, and MCM3AP-AS1 overexpression accelerated the proliferation, migration and invasion of NSCLC cells. In addition, MCM3AP-AS1 overexpression markedly up-modulated Bcl-2 expression and repressed Bax expression; MCM3AP-AS1 overexpression also significantly up-regulated N-cadherin expression and suppressed E-cadherin expression in NSCLC cells. What is more, in NSCLC cells, miR-195-5p was a target of MCM3AP-AS1, and the latter worked as a molecular sponge for miR-195-5p to regulate E2F3 expression. Collectively, MCM3AP-AS1, serving as a competitive endogenous RNA (ceRNA) to regulate miR-195-5p/E2F3 axis, promotes NSCLC progression, which is a promising therapeutic target for NSCLC.

A real-world study in advanced non-small cell lung cancer with de novo brain metastasis

Brain metastases are the major cause of life-expectancy shortened for patients with lung cancer. The prognostic value of EGFR mutation subtypes and survival benefit of EGFR-tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC) patients with de novo brain metastasis is still not clear. Here, we present a real-world study nation-wide focusing on the prognostic value of genomic and therapeutic factors in overall survival (OS) of those patients. We enrolled a total of 233 patients diagnosed with advanced NSCLC and de novo BM from multi-medical centers across China. The enrolled patients were divided into 4 groups, including EGFR 19del, EGFR L858R, EGFR wild-type, and EGFR unknown groups. The median OS of patients with EGFR mutations and all patients were 29.0 and 25.0 months, respectively. There was significant difference in OS of patients among EGFR 19del (n=76), EGFR L858R (n=94), EGFR wild-type (n=46) and EGFR unknown (n=17) groups (30.5 vs 27.5 vs 16.0 vs 25.0, P=0.025). Patients treated by icotinib showed better OS than gefitinib and erlotinib (31.0 vs 25.5 vs 26.5, P=0.02). There was a difference in OS of patients received the whole-brain radiotherapy (WBRT), stereotactic radiosurgery (SRS), or WBRT+SRS (20.0 vs 31.0 vs 30.0 months, P<0.001), respectively. In multivariate analysis, patients treated with icotinib had superior iPFS benefit than gefitinib and erlotinib (HR=0.86[95%CI (0.74-1.0)], P=0.04). Besides, the histology of non-adenocarcinomas, the number of BM (>3), and extracranial metastases status could have an independent negative impact on the OS of all patients (P<0.001). EGFR mutant NSCLC patients with de novo BM had a better OS than patients with EGFR wild type. Patients treated with icotinib had longer iPFS than gefitinib and erlotinib but not in OS. Non-adenocarcinomas, number of BM (>3) and extracranial metastases were independent negative prognostic factors in iPFS and OS of all patients. Prospective clinical trials are warranted to explore more effective multimodality in this population.

microRNAs Orchestrate Pathophysiology of Breast Cancer Brain Metastasis: Advances in Therapy

Brain metastasis (BM) predominantly occurs in triple-negative (TN) and epidermal growth factor 2 (HER2)-positive breast cancer (BC) patients, and currently, there is an unmet need for the treatment of these patients. BM is a complex process that is regulated by the formation of a metastatic niche. A better understanding of the brain metastatic processes and the crosstalk between cancer cells and brain microenvironment is essential for designing a novel therapeutic approach. In this context, the aberrant expression of miRNA has been shown to be associated with BM. These non-coding RNAs/miRNAs regulate metastasis through modulating the formation of a metastatic niche and metabolic reprogramming via regulation of their target genes. However, the role of miRNA in breast cancer brain metastasis (BCBM) is poorly explored. Thus, identification and understanding of miRNAs in the pathobiology of BCBM may identify a novel candidate miRNA for the early diagnosis and prevention of this devastating process. In this review, we focus on understanding the role of candidate miRNAs in the regulation of BC brain metastatic processes as well as designing novel miRNA-based therapeutic strategies for BCBM.

Brain metastases from non-small cell lung cancer with EGFR or ALK mutations: A systematic review and meta-analysis of multidisciplinary approaches

BACKGROUND AND PURPOSE

To analyze outcomes of non-small cell lung cancer (NSCLC) patients with brain metastases harboring EGFR or ALK mutations and examine for differences between tyrosine kinase inhibitors (TKIs) alone, radiotherapy (RT) alone (either whole brain radiation therapy (WBRT) or stereotactic radiosurgery (SRS)), or combined TKIs and RT.

MATERIALS AND METHODS

Thirty studies were identified.

PATIENTS

with brain metastases from NSCLC.

INTERVENTION

initial TKIs alone with optional salvage RT, RT alone, or TKIs and RT.

CONTROL

wild-type NSCLC and TKIs alone for mutational and treatment analysis, respectively.

OUTCOMES

overall survival (OS) and intracranial progression-free survival (PFS).

SETTING

studies with mutation information.

RESULTS

A total of 2649 patients were included. Patients with ALK and EGFR mutations had significantly higher median OS (48.5 months, p < 0.0001; and 20.9 months; p = 0.0006, respectively) compared to wild-type patients (9.9 months). Similar median OS was noted between TKIs and RT (28.3 months), RT alone (32.2 months; p = 0.22), or TKIs alone (23.9 months; p = 0.2). Patients treated with TKIs and RT had higher median PFS (18.6 months; p = 0.06) compared to TKIs alone (13.6 months) with no difference between TKIs and RT vs. RT alone (16.9 months; p = 0.72). No PFS difference was found between WBRT and TKI (23.2 months; p = 0.72) vs. WBRT alone (24 months) or SRS and TKI (16.7 months; p = 0.56) vs. SRS alone (13.6 months).

CONCLUSION

NSCLC patients with brain metastases harboring EGFR or ALK mutations have superior OS compared to wild-type patients. No PFS or OS benefit was found with the addition of TKIs to RT.

[Prognostic Analysis of EGFR-TKIs Combined with Gamma Knife in EGFR-mutant Lung Adenocarcinoma with Brain Metastasis]

背景与目的

晚期表皮生长因子受体（epidermal growth factor receptor, EGFR）基因突变的肺腺癌在初诊或治疗过程中脑转移的总发生率高，局部治疗联合系统性靶向治疗可能是更佳策略。本研究拟探讨分析EGFR酪氨酸激酶抑制剂（tyrosine kinase inhibitors, TKIs）联合头颅伽玛刀治疗EGFR突变的肺腺癌伴脑转移患者的疗效及预后因素。

方法

回顾性收集EGFR基因突变的肺腺癌、在初诊即存在脑转移或在EGFR-TKIs治疗过程中肺部病灶稳定而出现脑转移、接受一线口服EGFR-TKIs靶向治疗联合脑部伽玛刀局部治疗的患者，评价EGFR-TKIs联合头颅伽马刀治疗对颅内病灶的疗效，随访并分析颅内无进展生存时间（intracranial progression free survival, i-PFS），探索EGFR突变肺腺癌伴脑转移的预后因素。

结果

共纳入74例患者，其中位i-PFS为14.7个月，1年无颅内进展率为58.5%，2年无颅内进展率为22.2%。颅内病灶与肺部病灶具有相近的进展时间。单因素生存分析显示，初诊癌胚抗原（carcinoembryonic antigen, CEA）水平 < 10 ng/mL（16.9个月vs 12.6个月，P=0.012）、颅内病灶长径 < 2 cm（15.4个月vs 10.8个月，P=0.021）、肺癌脑转移分级预后系统（lung graded prognostic assessment, Lung-molGPA）评分 > 3（15个月vs 12.6个月，P=0.041）的患者具有更长的i-PFS。多因素分析显示初诊时CEA≥10 ng/mL和颅内病灶≥2 cm是i-PFS的不良预后因素。

结论

EGFR-TKIs联合伽玛刀局部治疗对EGFR突变肺腺癌伴脑转移患者的颅内病灶具有良好的疗效。初诊时CEA水平≥10 ng/mL、颅内病灶≥2 cm是接受EGFR-TKIs联合伽马刀治疗的脑转移肺腺癌患者的不良预后因素。