Effects of epidermal growth factor receptor-tyrosine kinase inhibitors alone on EGFR-mutant non-small cell lung cancer with brain metastasis

Central Nervous System Outcomes of Lazertinib Versus Gefitinib in EGFR-Mutated Advanced NSCLC: A LASER301 Subset Analysis

INTRODUCTION

Lazertinib, a third-generation mutant-selective EGFR tyrosine kinase inhibitor, improved progression-free survival compared with gefitinib in the phase 3 LASER301 study (ClinicalTrials.gov Identifier: NCT04248829). Here, we report the efficacy of lazertinib and gefitinib in patients with baseline central nervous system (CNS) metastases.

METHODS

Treatment-naive patients with EGFR-mutated advanced NSCLC were randomized one-to-one to lazertinib (240 mg/d) or gefitinib (250 mg/d). Patients with asymptomatic or stable CNS metastases were included if any planned radiation, surgery, or steroids were completed more than 2 weeks before randomization. For patients with CNS metastases confirmed at screening or subsequently suspected, CNS imaging was performed every 6 weeks for 18 months, then every 12 weeks. End points assessed by blinded independent central review and Response Evaluation Criteria in Solid Tumors version 1.1 included intracranial progression-free survival, intracranial objective response rate, and intracranial duration of response.

RESULTS

Of the 393 patients enrolled in LASER301, 86 (lazertinib, n = 45; gefitinib, n = 41) had measurable and or non-measurable baseline CNS metastases. The median intracranial progression-free survival in the lazertinib group was 28.2 months (95% confidence interval [CI]: 14.8-28.2) versus 8.4 months (95% CI: 6.7-not reached [NR]) in the gefitinib group (hazard ratio = 0.42, 95% CI: 0.20-0.89, p = 0.02). Among patients with measurable CNS lesions, the intracranial objective response rate was numerically higher with lazertinib (94%; n = 17) versus gefitinib (73%; n = 11, p = 0.124). The median intracranial duration of response with lazertinib was NR (8.3-NR) versus 6.3 months (2.8-NR) with gefitinib. Tolerability was similar to the overall LASER301 population.

CONCLUSIONS

In patients with CNS metastases, lazertinib significantly improved intracranial progression-free survival compared with gefitinib, with more durable responses.

The role of targeted therapy and immune therapy in the management of non-small cell lung cancer brain metastases

Brain metastases are a significant source of morbidity and mortality in patients with non-small cell lung cancer. Historically, surgery and radiation therapy have been essential to maintaining disease control within the central nervous system due to poorly penetrant conventional chemotherapy. With the advent of targeted therapy against actionable driver mutations, there is potential to control limited and asymptomatic intracranial disease and delay local therapy until progression. In this review paper, intracranial response rates and clinical outcomes to biological and immune therapies are summarized from the literature and appraised to assist clinical decision making and identify areas for further research. Future clinical trials ought to prioritize patient-centered quality of life and neurocognitive measures as major outcomes and specifically stratify patients based on mutational marker status, disease burden, and symptom acuity.

EGFR mutant status and tyrosine-kinase inhibitors affect the GKRS outcomes for NSCLC brain metastases

OBJECTIVE

Tyrosine kinase inhibitors (TKIs) is the first-line treatment for EGFR-positive non-small cell lung cancer (NSCLC); however, its applicability to patients with wild-type NSCLC remains an issue of contention. This study compared the effects of gamma knife radiosurgery (GKRS) alone versus combining GKRS and TKIs in treating two genetic forms of NSCLC.

METHODS

This retrospective study examined 479 NSCLC patients with 1982 brain metastases who underwent GKRS and for whom imaging follow-up data or death records were available. All our patients were consecutive. All gene mutations were confirmed by lung biopsy. The three main endpoints in this study were overall survival (OS), local intracranial tumor control (LC), and distal intracranial tumor control (DC).

RESULTS

There were 296 NSCLC patients with EGFR positive: TKI treatment (n = 262) and without TKI treatment (n = 34). GKRS + TKIs was more effective than GKRS alone in terms of OS (HR 0.53, p = 0.085) and DC (HR 0.51, p < 0.001). There were 150 NSCLC patients with wild-type EGFR: TKI treatment (n = 50) and without TKI treatment (n = 100). GKRS + TKIs was less effective than GKRS alone in terms of OS (HR 1.82, p = 0.049) and DC (HR: 1.40, p = 0.011). We observed no difference in terms of LC in both genetic groups.

CONCLUSIONS

Combining GKRS with TKIs proved effective in EGFR positive NSCLC patients; however, we do not observe the similar results when combining GKRS with TKIs for patients with wild-type NSCLC.

Combined stereotactic radiosurgery and tyrosine kinase inhibitor therapy versus tyrosine kinase inhibitor therapy alone for the treatment of non-small cell lung cancer patients with brain metastases

OBJECTIVE

Whether combined radiation and tyrosine kinase inhibitor (TKI) therapy in non-small cell lung cancer (NSCLC) patients with brain metastases (BMs) and epidermal growth factor receptor (EGFR) mutations confers additional benefits over TKI therapy alone remains a matter of debate. The goal of this study was to compare outcomes between combined TKI therapy with stereotactic radiosurgery (SRS) versus TKI therapy alone in NSCLC patients with BMs and EGFR mutations.

METHODS

Consecutive cases of NSCLC patients with EGFR mutations and BMs treated with TKIs were selected for inclusion in this study. Patients were categorized into two groups based on SRS: TKI therapy alone (group I) and combined SRS and TKI therapy (group II). Patients who had SRS or TKI as salvage therapy and those with prior radiation treatment for BMs were excluded. Tumor control (< 10% increase in tumor volume) and overall survival (OS) rates were compared using Kaplan-Meier analyses. Independent predictors of tumor control and OS were identified using multivariable Cox regression analyses.

RESULTS

The study cohort comprised 280 patients (n = 90 in group I and n = 190 in group II). Cumulative tumor control rates were higher in group II than in group I (79.8% vs 31.2% at 36 months, p < 0.0001). Cumulative OS rates were comparable between groups I and II (43.8% vs 59.4% at 36 months, p = 0.3203). Independent predictors of tumor control were older age (p < 0.01, HR 1.03), fewer BMs (p < 0.01, HR 1.09), lack of extracranial metastasis (p < 0.02, HR 0.70), and combined SRS and TKI therapy (p < 0.01, HR 0.25). Independent predictors of OS were fewer BMs (p < 0.01, HR 1.04) and a higher Karnofsky Performance Status score (p < 0.01, HR 0.97).

CONCLUSIONS

Although the OS rate did not differ between TKI therapy with and without SRS, the addition of SRS to TKI therapy resulted in improvement of intracranial tumor control. The lack of effect on survival rate with the addition of SRS may be attributable to extracranial disease progression. The addition of SRS to TKI therapy is recommended for intracranial disease control in NSCLC patients with BMs and EGFR mutations. Potential benefits may include prevention of neurological deficits and seizures. Future prospective studies may help clarify the clinical outcome benefits of SRS in these patients.

The effect of smoking on survival in lung carcinoma patients with brain metastasis: a systematic review and meta-analysis

The effects of smoking on survival in BM patients have yet to be reviewed and meta-analysed. However, previous studies have shown that smokers had a greater risk of dying from lung cancer compared to non-smokers. This meta-analysis, therefore, aimed to analyse the effects of cigarette smoking on overall survival (OS) and progression-free survival (PFS) in lung cancer BM patients. PubMed, Embase, Web of Science, Cochrane and Google Scholar were searched for comparative studies regarding the effects of smoking on incidence and survival in brain metastases patients up to December 2020. Three independent reviewers extracted overall survival (OS) and progression-free survival data (PFS). Random-effects models were used to pool multivariate-adjusted hazard ratios (HR). Out of 1890 studies, fifteen studies with a total of 2915 patients met our inclusion criteria. Amongst lung carcinoma BM patients, those who were smokers (ever or yes) had a worse overall survival (HR: 1.34, 95% CI 1.13, 1.60, I2: 72.1%, p-heterogeneity < 0.001) than those who were non-smokers (never or no). A subgroup analysis showed the association to remain significant in the ever/never subgroup (HR: 1.34, 95% CI 1.11, 1.63) but not in the yes/no smoking subgroup (HR: 1.30, 95% CI 0.44, 3.88). This difference between the two subgroups was not statistically significant (p = 0.91). Amongst lung carcinoma BM patients, smoking was associated with a worse OS and PFS. Future studies examining BMs should report survival data stratified by uniform smoking status definitions.

Eligibility Criteria and Endpoints in Metastatic Renal Cell Carcinoma Trials

OBJECTIVES

Treatments for metastatic renal cell carcinoma (mRCC) are often compared across trials, but trial eligibility criteria and endpoints differ. In an effort to better align trials, the Definition for the Assessment of Time to event Endpoints in CANcer trials (DATECAN) project published recommendations in 2015 to be used in mRCC clinical trial design. We analyzed mRCC trial criteria to determine if DATECAN's recommendations were followed.

MATERIALS AND METHODS

We compared eligibility criteria across 29 phase 3 mRCC trials conducted between 2003 and 2019. We then evaluated endpoints used in 10 phase 3 trials activated between 2015 and 2019 to determine their compliance with DATECAN's recommendations.

RESULTS

Among the 29 trials, performance status, renal function, and disease characteristics differed in terms of requirements and measures used. In terms of endpoints, the 10 trials did not entirely follow DATECAN's recommendations. In total, 7/10 trials' primary endpoint was progression-free survival (PFS) as recommended; 4/9 trials used PFS as an endpoint but did not publish their definition of PFS, and the 5 that did, included "death from any cause" instead of DATECAN's recommendation of "death from kidney cancer."

CONCLUSIONS

Key eligibility criteria were somewhat inconsistent across the phase 3 mRCC trials studied. Endpoints in the newer trials did not align with DATECAN's recommendations. Not only is greater standardization needed to facilitate meta-analyses and cross-trial comparisons, but as evident from lack of adherence to DATECAN's recommendations, greater promotion and adoption of recommendations are needed to better harmonize trial design.

Icotinib is as efficacious as gefitinib for brain metastasis of EGFR mutated non-small-cell lung cancer

BACKGROUND

The prognosis of non-small-cell lung cancer (NSCLC) with brain metastases is very poor. Currently, therapeutic methods for this patient population include whole-brain radiation therapy (WBRT), surgery, radiosurgery and systemic treatment. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) could be effective on cerebral metastases of mutated NSCLC. However, which EGFR-TKIs is more appropriate is still unknown.

METHODS

We conducted a retrospective analysis of advanced NSCLC patients with brain metastases for EGFR targeted therapy from November 2013 to April 2018 at Dongguan People's Hospital, Southern Medical University, China. A total of 43 patients were recruit in this study. Among them, 21 cases received icotinib (125 mg, thrice a day) and 22 cases received gefitinib (250 mg, once a day) until disease progression or unacceptable toxicity. The primary end point of this study was intracranial PFS (iPFS). The relationships between therapeutic arms and patients characteristics were performed using Pearson's chi-square test or Fisher's exact test. The differences in PFS among the two arms were analyzed using Kaplan-Meier curves and log rank tests.

RESULTS

There was no significant difference of intracranial ORR (66.6% versus 59.1%, P = 0.62) and DCR (85.7% versus 81.8%, P = 0.73) between the two arms. The median intracranial PFS (iPFS) for icotinib and gefitinib arms were 8.4 months (95% CI, 5.4 to 11.3 months) and 10.6 months (95% CI, 6.3 to 14.8 months), respectively (P = 0.17). Adverse events of the two study arms were generally mild. None of the patients experienced dose reduction of EGFR-TKIs.

CONCLUSIONS

Our study showed that icotinib and gefitinib had similar efficacy for brain metastasis of EGFR mutated NSCLC. Large randomized studies are suggested to further illuminate the effect of these two EGFR-TKIs on cerebral lesions of NSCLC.

Multidisciplinary expert opinion on the treatment consensus for patients with EGFR mutated NSCLC with brain metastases

The presence of an epidermal growth factor receptor (EGFR) mutation is associated with higher incidence of brain metastases in patients with non-small cell lung cancer (NSCLC); however, patients with synchronous brain metastases at diagnosis have generally been excluded from clinical trials. As there is limited clinical evidence for managing this patient population, a multidisciplinary group of Spanish medical and radiation oncologists, and neuro-oncologist with expertise treating brain metastases in lung cancer patients met with the aim of reaching and developing an expert opinion consensus on the management of patients with EGFR mutated NSCLC with brain metastases. This consensus contains 26 recommendations and 20 conclusion statements across 21 questions in 7 areas, as well as a first-line treatment algorithm.

Predictive value of microRNA let-7a expression for efficacy and prognosis of radiotherapy in patients with lung cancer brain metastasis: A case-control study

BACKGROUND

As a well-known cancer with high mortality, lung cancer has been implied to be closely associated with brain metastasis. Despite notable advances, effective treatment methods are still in urgent need. This study aims to investigate the value of serum microRNA-let-7a (miR-let-7a) expression in predicting efficacy and prognosis of radiotherapy in patients with lung cancer brain metastasis.

METHODS

To begin with, reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed for better understand of the correlation between miR-let-7a and lung cancer. Afterwards, the relationship between serum miR-let-7a expression and radiotherapy efficacy was analyzed by receiver operating characteristic curve analysis. Following successful transfection, RT-qPCR and Western blot assay were utilized for evaluating the involvement of miR-let-7a in regulation of DICER1 expression in lung cancer cell line. Then, whether miR-let-7a was implicated in proliferation and cell cycle distribution of lung cancer cells were confirmed by cell counting kit-8 assay and flow cytometry respectively.

RESULTS

Initially, it was revealed that serum miR-let-7a expression was decreased in lung cancer. Later, we found that decreased miR-let-7a displayed an unfavorable role in radiotherapy efficacy and overall survival rate of patients with lung cancer brain metastasis. After the successful transfection, the inverse relationship between miR-let-7a and DICER1 expression was uncovered. Meanwhile, biological behaviors of lung cancer cells were presented to be limited after transfection of overexpressed miR-let-7a.

CONCLUSION

Our findings demonstrated that the lower expression of miR-let-7a in patients with lung cancer brain metastasis was closely related to unfavorable efficacy and prognosis of radiotherapy, and it may be an important predictive biomarker by regulation of DICER1.

Management of Brain Metastases in Epidermal Growth Factor Receptor Mutant Non-Small-Cell Lung Cancer

Lung cancer remains a leading cause of mortality with 1.69 million deaths worldwide. Activating mutations in epidermal growth factor receptor (EGFR), predominantly exon 19 deletions and exon 21 L858R mutations, are known oncogenic drivers identified in 20-40% of non-small-cell lung cancers (NSCLC). 70% of EGFR-mutant NSCLC patients develop brain metastases (BM), compared to 38% in EGFR wild-type patients. First-generation tyrosine kinase inhibitors (TKIs), such as erlotinib and gefitinib have proven to be superior to chemotherapy in the front-line treatment of EGFR-mutant NSCLC, as has afatinib, a second-generation TKI. The most common acquired resistance mechanism is the development of a gatekeeper mutation in exon 20 T790M. Osimertinib has emerged as a third-generation EGFR TKI with proven activity in the front-line setting as well as in patients with a T790M acquired resistance mutation with remarkable CNS activity. As long-term survival outcomes in EGFR-mutant NSCLC continue to improve, the burden of BM becomes a greater challenge. Here, we review the literature related to the management of BM in EGFR-mutant NSCLC including the role of the three generations of EGFR TKIs, immunotherapy, and brain radiation.

Role of Epidermal Growth Factor Receptor (EGFR) Inhibitors and Radiation in the Management of Brain Metastases from EGFR Mutant Lung Cancers

The growth of genotype-directed targeted therapies, such as inhibitors of the epidermal growth factor receptor (EGFR), has revolutionized treatment for some patients with oncogene-addicted lung cancer. However, as systemic control for these patients has improved, brain metastases remain an important source of morbidity and mortality. Traditional treatment for brain metastases has been radiotherapy, either whole-brain radiation or stereotactic radiosurgery. The growing availability of drugs that can cross the blood-brain barrier and have activity in the central nervous system (CNS) has led to many studies investigating whether targeted therapy can be used in combination with or in lieu of radiation. In this review, we summarize the key literature about the incidence and nature of EGFR-mutant brain metastases (EGFR BMs), the data about the activity of EGFR inhibitors in the CNS, and whether they can be used as front-line therapy for brain metastases. Although initial use of tyrosine kinase inhibitors for EGFR BMs can often be an effective treatment strategy, multidisciplinary evaluation is critical, and prospective studies are needed to clarify which patients may benefit from early radiotherapy.

IMPLICATIONS FOR PRACTICE

Management of brain metastases in epidermal growth factor receptor (EGFR) mutant lung cancer is a common clinical problem. The question of whether to start initial therapy with an EGFR inhibitor or radiotherapy (either whole-brain radiotherapy or stereotactic radiosurgery) is controversial. The development of novel EGFR inhibitors with enhanced central nervous system (CNS) penetration is an important advance in the treatment of CNS disease. Multidisciplinary evaluation and evaluation of extracranial disease status are critical to choosing the best treatment option for each patient.

Brain Metastases in Oncogene-Addicted Non-Small Cell Lung Cancer Patients: Incidence and Treatment

Brain metastases (BM) are common in non-small cell lung cancer patients including in molecularly selected populations, such as EGFR-mutant and ALK-rearranged tumors. They are associated with a reduced quality of life, and are commonly the first site of progression for patients receiving tyrosine kinase inhibitors (TKIs). In this review, we summarize incidence of BM and intracranial efficacy with TKI agents according to oncogene driver mutations, focusing on important clinical issues, notably optimal first-line treatment in oncogene-addicted lung tumors with upfront BM (local therapies followed by TKI vs. TKI monotherapy). We also discuss the potential role of newly emerging late-generation TKIs as new standard treatment in oncogene-addicted lung cancer tumors compared with sequential strategies.

A Neuro-oncologist's Perspective on Management of Brain Metastases in Patients with EGFR Mutant Non-small Cell Lung Cancer

Management of non-small cell lung cancer (NSCLC) with brain metastasis (BrM) has been revolutionized by identification of molecular subsets that have targetable oncogenes. Historically, survival for NSCLC with symptomatic BrM was weeks to months. Now, many patients are surviving years with limited data to guide treatment decisions. Tumors with activating mutations in epidermal growth factor receptor (EGFRact+) have a higher incidence of BrM, but a longer overall survival. The high response rate of both systemic and BrM EGFRact+ NSCLC to tyrosine kinase inhibitors (TKIs) has led to the rapid incorporation of new therapies but is outpacing evidence-based decisions for BrM in NSCLC. While whole brain radiation therapy (WBRT) was the foundation of management of BrM, extended survival raises concerns for the subacute and late effects radiotherapy. We favor the use of TKIs and delaying the use of WBRT when able. At inevitable disease progression, we consider alternative dosing schedules to increase CNS penetration (such as pulse dosing of erlotinib) or advance to next generation TKI if available. We utilize local control options of surgery or stereotactic radiosurgery (SRS) for symptomatic accessible lesions based on size and edema. At progression despite available TKIs, we use pemetrexed-based platinum doublet chemotherapy or immunotherapy if the tumor has high expression of PDL-1. We reserve the use of WBRT for patients with more than 10 BrM and progression despite TKI and conventional chemotherapy, if performance status is appropriate.