Gefitinib in Patients with Brain Metastases from Non–Small-Cell Lung Cancer: Review of 15 Clinical Cases

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.

Trametinib overcomes KRAS-G12V-induced osimertinib resistance in a leptomeningeal carcinomatosis model of EGFR-mutant lung cancer

Leptomeningeal carcinomatosis (LMC) occurs frequently in non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations and is associated with acquired resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs). However, the mechanism by which LMC acquires resistance to osimertinib, a third-generation EGFR-TKI, is unclear. In this study, we elucidated the resistance mechanism and searched for a novel therapeutic strategy. We induced osimertinib resistance in a mouse model of LMC using an EGFR-mutant NSCLC cell line (PC9) via continuous oral osimertinib treatment and administration of established resistant cells and examined the resistance mechanism using next-generation sequencing. We detected the Kirsten rat sarcoma (KRAS)-G12V mutation in resistant cells, which retained the EGFR exon 19 deletion. Experiments involving KRAS knockdown in resistant cells and KRAS-G12V overexpression in parental cells revealed the involvement of KRAS-G12V in osimertinib resistance. Cotreatment with trametinib (a MEK inhibitor) and osimertinib resensitized the cells to osimertinib. Furthermore, in the mouse model of LMC with resistant cells, combined osimertinib and trametinib treatment successfully controlled LMC progression. These findings suggest a potential novel therapy against KRAS-G12V-harboring osimertinib-resistant LMC in EGFR-mutant NSCLC.

Therapeutic Drug Monitoring of Targeted Anticancer Protein Kinase Inhibitors in Routine Clinical Use: A Critical Review

BACKGROUND

Therapeutic response to oral targeted anticancer protein kinase inhibitors (PKIs) varies widely between patients, with insufficient efficacy of some of them and unacceptable adverse reactions of others. There are several possible causes for this heterogeneity, such as pharmacokinetic (PK) variability affecting blood concentrations, fluctuating medication adherence, and constitutional or acquired drug resistance of cancer cells. The appropriate management of oncology patients with PKI treatments thus requires concerted efforts to optimize the utilization of these drug agents, which have probably not yet revealed their full potential.

METHODS

An extensive literature review was performed on MEDLINE on the PK, pharmacodynamics, and therapeutic drug monitoring (TDM) of PKIs (up to April 2019).

RESULTS

This review provides the criteria for determining PKIs suitable candidates for TDM (eg, availability of analytical methods, observational PK studies, PK-pharmacodynamics relationship analysis, and randomized controlled studies). It reviews the major characteristics and limitations of PKIs, the expected benefits of TDM for cancer patients receiving them, and the prerequisites for the appropriate utilization of TDM. Finally, it discusses various important practical aspects and pitfalls of TDM for supporting better implementation in the field of cancer treatment.

CONCLUSIONS

Adaptation of PKIs dosage regimens at the individual patient level, through a rational TDM approach, could prevent oncology patients from being exposed to ineffective or unnecessarily toxic drug concentrations in the era of personalized medicine.

Enhancement degree of brain metastases: correlation analysis between enhanced T2 FLAIR and vascular permeability parameters of dynamic contrast-enhanced MRI

OBJECTIVES

To investigate the correlation between enhancement degrees of brain metastases on contrast-enhanced T2-fluid-attenuated inversion recovery (CE-T2 FLAIR) and vascular permeability parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

METHODS

Thirty-nine patients with brain metastases were prospectively collected. They underwent non-enhanced T2 FLAIR, DCE-MRI, CE-T2 FLAIR, and contrast-enhanced three-dimensional brain volume imaging (CE-BRAVO). Quantitative parameters of DCE-MRI were evaluated for all lesions, which included volume transfer constant (K^trans), rate constant (K_ep), and fractional volume of the extracellular extravascular space (V_e). Contrast ratio (CR) and percentage increase (PI) values of all lesions on CE-T2 FLAIR were also measured. The tumor enhancement degree on CE-T2 FLAIR in relation to CE-BRAVO was visually classified as higher (group A), equal (group B), and lower (group C).

RESULTS

A total of 82 brain metastases were evaluated, including 31 in group A, 19 in group B, and 32 in group C. The K^trans and K_ep were negatively correlated with the CR (ρ = - 0.551, p < 0.001 and ρ = - 0.708, p < 0.001, respectively) and PI (ρ = - 0.511, p < 0.001 and ρ = - 0.621, p < 0.001, respectively). The K^trans and K_ep of group A were significantly lower than those of group C (both p < 0.001). No significant difference was found in V_e among the groups (p = 0.327).

CONCLUSIONS

The enhancement degree of brain metastases on CE-T2 FLAIR is negatively correlated with K^trans and K_ep values, which indicate that vascular permeability parameters may play an important role in explaining the difference in enhancement between CE-T2 FLAIR and CE-BRAVO.

KEY POINTS

• The enhancement degree on CE-T2 FLAIR was negatively correlated with K^trans and K_ep values. • The vascular permeability of brain metastasis accounted for the difference in enhancement degree between CE-T2 FLAIR and CE-BRAVO. • CE-T2 FLAIR is useful for detecting brain metastases with mild disruption of the blood-brain barrier.

Safety and CSF distribution of high-dose erlotinib and gefitinib in patients of non-small cell lung cancer (NSCLC) with brain metastases

PURPOSE

Patients of non-small cell lung cancer (NSCLC) with brain metastases have limited treatment options. High-dose erlotinib (HDE) and gefitinib (HDG) have been tried in the past. This study investigates the cerebrospinal fluid (CSF) disposition and safety of both, high-dose erlotinib and gefitinib regimens.

METHODS

Eleven and nine patients were treated with erlotinib and gefitinib, respectively. All patients received 1 week of standard dose of erlotinib (150 mg OD) or gefitinib (250 mg OD), followed by the high dose (1500 mg weekly for erlotinib and 1250 mg OD for gefitinib) from day 8. Blood and CSF samples were collected on days 7 and 15, 4 h after the morning dose and drug levels determined using LC-MS/MS. Adverse events were documented as per CTCAE 4.03 till day 15.

RESULTS

Pulsatile HDE and daily HDG resulted in 1.4- and 1.9-fold increase in CSF levels, respectively. A constant 2% CSF penetration rate was observed across both doses of erlotinib, while for gefitinib the penetration rate for high dose was half that of the standard dose suggesting a nonlinear disposition. Three patients on HDE treatment discontinued treatment after the first dose due to intolerable toxicities, whereas HDG was better tolerated with no treatment discontinuations. Since CSF disposition of gefitinib followed saturable kinetics, a lower dose of 750 mg was found to achieve CSF concentrations comparable to that of the 1250 mg dose.

CONCLUSIONS

HDG was better tolerated than HDE. CSF disposition of gefitinib was found to be saturable at a higher dose. Based on these findings, the dose of 750 mg OD should be considered for further evaluation in this setting.

Osimertinib Overcomes Alectinib Resistance Caused by Amphiregulin in a Leptomeningeal Carcinomatosis Model of ALK-Rearranged Lung Cancer

INTRODUCTION

Leptomeningeal carcinomatosis (LMC) occurs frequently in anaplastic lymphoma kinase (ALK)-rearranged NSCLC and develops acquired resistance to ALK tyrosine kinase inhibitors (ALK TKIs). This study aimed to clarify the resistance mechanism to alectinib, a second-generation ALK TKI, in LMC and test a novel therapeutic strategy.

METHODS

We induced alectinib resistance in an LMC mouse model with ALK-rearranged NSCLC cell line, A925LPE3, by continuous oral alectinib treatment, established A925L/AR cells. Resistance mechanisms were analyzed using several assays, including Western blot and receptor tyrosine kinase array. We also measured amphiregulin (AREG) concentrations in cerebrospinal fluid from patients with ALK-rearranged NSCLC with alectinib-refractory LMC by enzyme-linked immunosorbent assay.

RESULTS

A925L/AR cells were moderately resistant to various ALK TKIs, such as alectinib, crizotinib, ceritinib, and lorlatinib, compared with parental cells in vitro. A925L/AR cells acquired the resistance by EGFR activation resulting from AREG overexpression caused by decreased expression of microRNA-449a. EGFR TKIs and anti-EGFR antibody resensitized A925L/AR cells to alectinib in vitro. In the LMC model with A925L/AR cells, combined treatment with alectinib and EGFR TKIs, such as erlotinib and osimertinib, successfully controlled progression of LMC. Mass spectrometry imaging showed accumulation of the EGFR TKIs in the tumor lesions. Moreover, notably higher AREG levels were detected in cerebrospinal fluid of patients with alectinib-resistant ALK-rearranged NSCLC with LMC (n = 4), compared with patients with EGFR-mutated NSCLC with EGFR TKI-resistant LMC (n = 30), or patients without LMC (n = 24).

CONCLUSIONS

These findings indicate the potential of novel therapies targeting both ALK and EGFR for the treatment of ALK TKI-resistant LMC in ALK-rearranged NSCLC.

Clinical factors associated with treatment outcomes in EGFR mutant non-small cell lung cancer patients with brain metastases: a case-control observational study

Background

Non-small cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations often develop brain metastases. Treatment with EGFR-tyrosine kinase inhibitors (TKIs) has shown the effectiveness; however, knowledge of the clinical factors associated with outcomes in NSCLC patients with EGFR mutations remains limited.

Methods

Treatment-naive patients diagnosed with advanced non-squamous NSCLC with brain metastases harboring EGFR mutations and treated with an EGFR-TKI as first-line therapy were enrolled with analysis of their medical records.

Results

A total of 134 advanced NSCLC patients with brain metastases harboring EGFR mutations received an EGFR-TKI (gefitinib: 62, erlotinib: 49, and afatinib: 23) as the first-line therapy. Sixty-nine had exon 19 deletions (51.5%), and 56 (41.8%) had L858R mutations. There was no statistically significant difference in progression-free survival (PFS) and overall survival (OS) among the EGFR-TKIs. Significantly shorter OS was noted in patients with multiple brain metastases (hazard ratio [HR]: 2.43, p = 0.007), uncommon EGFR mutations (HR: 3.75, p = 0.009), and liver metastases. Thirty-eight patients (29.1%) received brain radiotherapy for brain metastases before disease progression, and had a significantly longer time until intracranial progression. However, the brain radiotherapy had no statistically significant impact on PFS or OS.

Conclusions

Patients with uncommon mutations, multiple brain metastases, and concomitant liver metastases tended to have shorter OS. Brain radiotherapy could delay the time to intracranial disease progression but had no impact on survival. The different first-line EGFR-TKIs achieved similar treatment responses in terms of PFS and OS in the EGFR-mutated NSCLC patients with brain metastases.

Comparison of the efficacies of first-generation epidermal growth factor receptor tyrosine kinase inhibitors for brain metastasis in patients with advanced non-small-cell lung cancer harboring EGFR mutations

BACKGROUND

Compared with standard chemotherapy, epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are more effective in patients with advanced non-small-cell lung cancer (NSCLC) harboring EGFR mutations. However, data comparing the efficacies of different EGFR-TKIs, especially regarding the presence of brain metastasis, are lacking.

METHODS

EGFR-TKI naive patients with recurrent or stage IIIB/IV NSCLC harboring EGFR mutations, excluding resistance mutations, were enrolled in this study. We retrospectively determined progression-free survival (PFS) using the Kaplan-Meier method with log-rank test in patients treated with either gefitinib or erlotinib, cumulative incidence of central nervous system (CNS) progression using the Fine and Gray competing risk regression model, and favorable prognostic factors for CNS progression by multivariate analysis.

RESULTS

Seventy-seven EGFR-TKI-naive patients were started on either gefitinib (n = 55) or erlotinib (n = 22) in our hospital from April 2010 to April 2016. Among the patients with brain metastasis, PFS tended to be longer in the erlotinib than in the gefitinib group. In the analysis of cumulative incidence, the probability of CNS progression was lower in the erlotinib group than in the gefitinib group. Particularly, in a subgroup analysis of the patients with brain metastasis, there was a significant difference between the erlotinib and gefitinib groups (hazard ratio 0.25; 95% confidence interval, 0.08-0.81; p = 0.021). Of the prognostic factors for CNS progression evaluated, the absence of brain metastasis before EGFR-TKI therapy and receiving erlotinib (vs gefitinib) had a significantly favorable effect on patient prognosis.

CONCLUSION

Although this was a retrospective analysis involving a small sample size, erlotinib is potentially more promising than gefitinib for treatment of brain metastasis in patients with EGFR-mutant NSCLC.

Effect of erlotinib plus bevacizumab on brain metastases in patients with non-small cell lung cancer

Background

The standard therapy for brain metastasis (BM) in non-small cell lung cancer (NSCLC) is radiation therapy (RT), although it is associated with complications such as leukoencephalopathy. In the current report, we retrospectively review data from eight patients who had NSCLC and harbored epidermal growth factor receptor (EGFR) mutations, and who were received erlotinib plus bevacizumab (E+B) as first-line therapy for BM.

Methods

Patients were given E+B as first therapy for BM until August 2017 at our institution. Patients receiving local therapy for BM, such as surgery or radiotherapy, were excluded. Patients were administered erlotinib orally (once daily at 150 mg/body) plus bevacizumab by intravenous infusion (15 mg/kg on day 1 of a 21- or 28-day cycle).

Results

Eight NSCLC patients who were diagnosed with BM received E+B, including 2 men and 6 women with a median age of 65 years (range, 46-84 years). Four patients had an L858R EGFR mutation, while the other four had an exon 19 deletion. Seven patients had a partial response to E+B treatment, and one had a complete response. The 2-year survival rate was 62.5%. Three patients who were pre-treated with gefitinib had an E+B treatment duration of less than 1 year. At the time of this analysis, four patients had BM-related neurologic symptoms and multiple BMs, and were still receiving E+B with no evidence of treatment failure after more than 1 year.

Conclusions

E+B can be used as first-line therapy for BM, even in patients with BM-related neurologic symptoms and multiple BMs.

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.

The Evolving Landscape of Brain Metastasis

Metastasis, involving the spread of systemic cancer to the brain, results in neurologic disability and death. Current treatments are largely palliative in nature; improved therapeutic approaches represent an unmet clinical need. However, recent experimental and clinical advances challenge the bleak long-term outcome of this disease. Encompassing key recent findings in epidemiology, genetics, microenvironment, leptomeningeal disease, neurocognition, targeted therapy, immunotherapy, and prophylaxis, we review preclinical and clinical studies to provide a comprehensive picture of contemporary research and the management of secondary brain tumors.

Bevacizumab and gefitinib enhanced whole-brain radiation therapy for brain metastases due to non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) patients who experience brain metastases are usually associated with poor prognostic outcomes. This retrospective study proposed to assess whether bevacizumab or gefitinib can be used to improve the effectiveness of whole brain radiotherapy (WBRT) in managing patients with brain metastases. A total of 218 NSCLC patients with multiple brain metastases were retrospectively included in this study and were randomly allocated to bevacizumab-gefitinib-WBRT group (n=76), gefitinib-WBRT group (n=77) and WBRT group (n=75). Then, tumor responses were evaluated every 2 months based on Response Evaluation Criteria in Solid Tumors version 1.0. Karnofsky performance status and neurologic examination were documented every 6 months after the treatment. Compared to the standard WBRT, bevacizumab and gefitinib could significantly enhance response rate (RR) and disease control rate (DCR) of WBRT (P<0.001). At the same time, RR and DCR of patients who received bevacizumab-gefitinib-WBRT were higher than those who received gefitinib-WBRT. The overall survival (OS) rates and progression-free survival (PFS) rates also differed significantly among the bevacizumab-gefitinib-WBRT (48.6 and 29.8%), gefitinib-WBRT (36.7 and 29.6%) and WBRT (9.8 and 14.6%) groups (P<0.05). Although bevacizumab-gefitinib-WBRT was slightly more toxic than gefitinib-WBRT, the toxicity was tolerable. As suggested by prolonged PFS and OS status, bevacizumab substantially improved the overall efficacy of WBRT in the management of patients with NSCLC.

Evaluation on efficacy and safety of the addition of X-knife therapy to gefitinib in NSCLC patients with symptomatic brain metastases

Background

Stereotactic radiosurgery (SRS) is a widely used therapy for brain metastases(BMs) in Non-small cell lung cancer(NSCLC). However, its role in symptomatic patients with EGFR mutation remains unclear. We have retrospectively reviewed the clinical data of patients with symptomatic BMs whom received SRS as a salvage approach and concurrent gifitinib therapy.

Methods

Seven patients with primary NSCLC, symptomatic BMs, and EGFR mutation were identified in a retrospective review of patients treated with SRS using X-knife at Guangdong 999 Brain Hospital between 1 January 2012 and 31 August 2014. The median follow-up of these patients was 16 months. Image fusion technique was used to determine cumulative doses to targeted lesions, whole brain, and critical brain structures. Toxicities and complications were identified by clinical records.

Results

SRS(X-knife) was selected to be performed on seven patients (two males and five females) diagnosed with NSCLC and EGFR mutation due to the presence of encephaledema, compression of ventricles, or other complications. Neurological symptoms (such as paresis, aphasia, sensory and visual disturbances) were not present in any patients before or after SRS treatment, and the postoperative Karnofsky performance status(KPS) was improved in all patients. Median overall survival(OS) was 16 months and median progression free survival(PFS) was 10 months.

Conclusions

The improvement of KPS and survival were reliable by SRS(X-knife) with concurrent gifitinib therapy in NSCLC patients with symptomatic BMs, and EGFR mutation. Given the small sample size, further prospective studies with a greater number of patients are warranted to confirm our results.

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.

Pulsatile Erlotinib in EGFR-Positive Non-Small-Cell Lung Cancer Patients With Leptomeningeal and Brain Metastases: Review of the Literature

Patients with epidermal growth factor receptor (EGFR)-positive (EGFR⁺) non-small-cell lung cancer (NSCLC) show improved response rates when treated with tyrosine kinase inhibitors (TKIs) such as erlotinib. However, standard daily dosing of erlotinib often does not reach therapeutic concentrations within the cerebrospinal fluid (CSF), resulting in progression of central nervous system (CNS) disease. Intermittent, high-dose administration of erlotinib reaches therapeutic concentrations within the CSF and is well tolerated in patients. Experience with "pulsatile" dosing, however, is limited. We review the literature on the pharmacology and clinical outcomes of pulsatile erlotinib in the treatment of EGFR⁺ NSCLC with brain and leptomeningeal metastases, and include available data on the use of next-generation TKIs in CNS progression. We also provide our institution's experience with patients treated with pulsatile erlotinib for CNS metastasis, and propose clinical criteria for its use. Pulsatile erlotinib is a reasonable alternative in EGFR⁺ patients with new or worsening CNS disease, without evidence of systemic progression, and without confirmed T790M resistance mutations within the CNS.

Downregulation of EGFR in a metastatic brain lesion of EGFR-mutated non-small cell lung cancer using a tyrosine kinase inhibitor: A case report

Brain metastasis is a common complication in patients with cancer, with lung cancer being the most frequent origin of brain metastases. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have begun to serve a pivotal role in lung cancer treatment and have been reported to demonstrate anticancer activity against brain metastases by penetrating the blood-brain barrier. The present study reports, to the best of our knowledge, the first case of EGFR-mutated non-small cell lung cancer (NSCLC) brain metastasis that was surgically resected while the lesion was responding to the EGFR-TKI erlotinib. The results of the present study demonstrated that EGFR-mutated NSCLC cells were able to evade the cytotoxic effect of EGFR-TKI by downregulating EGFR expression, without exhibiting the T790M EGFR mutation.

Rapid intracranial response to osimertinib, without radiotherapy, in nonsmall cell lung cancer patients harboring the EGFR T790M mutation: Two Case Reports

RATIONALE

Most of nonsmall cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) activating mutations eventually acquire resistance to the first EGFR-tyrosine kinase inhibitors (TKIs) therapy after varying periods of treatment. Of note, approximately one-third of those patients develop brain metastases, which deteriorate their quality of life and survival. The effect of systemic chemotherapy on brain metastases after acquisition of EGFR-TKI resistance is limited, and thus far, whole-brain radiation therapy, which may cause the harmful effect on neurocognitive functions, has been the only established therapeutic option for especially symptomatic brain metastases. Osimertinib is a third-generation oral, potent, and irreversible EGFR-TKI. It can bind to EGFRs with high affinity even when the EGFR T790M mutation exists in addition to the sensitizing mutations. Its clinical efficacy for NSCLC patients harboring the T790M mutation has already been shown; however, the evidence of osimertinib on brain metastases has not been documented well, especially in terms of the appropriate timing for treatment and its response evaluation.

PATIENT CONCERNS, DIAGNOSES, AND INTERVENTIONS

We experienced 2 NSCLC patients with the EGFR T790M mutation; a 67-year-old woman with symptomatic multiple brain metastases administered osimertinib as seventh-line chemotherapy, and a 76-year old man with an asymptomatic single brain metastasis administered osimertinib as fifth-line chemotherapy.

OUTCOMES

These patients showed great response to osimertinib within 2 weeks without radiation therapy.

LESSONS

These are the first reports to reveal the rapid response of the brain metastases to osimertinib within 2 weeks. These cases suggest the possibility that preemptive administration of osimertinib may help patients to postpone or avoid radiation exposures. In addition, rapid reassessment of the effect of osimertinib on brain metastases could prevent patients from being too late to receive essential radiotherapy.

Presence of pleural effusion is associated with a poor prognosis in patients with epidermal growth factor receptor-mutated lung cancer receiving tyrosine kinase inhibitors as first-line treatment

AIM

This study was conducted to evaluate the effect of clinical factors on the treatment outcomes of lung cancer patients with active epidermal growth factor receptor (EGFR) mutations treated by first-line tyrosine kinase inhibitors (TKIs).

METHODS

Patients of stage IIIb or IV lung adenocarcinoma harboring mutated EGFR were enrolled between March 2010 and June 2014 and followed up until December 2015. The effects of various clinical features, such as age, sex, smoking history, EGFR mutation types, TKIs used, presence of pleural effusion, metastatic sites on progression-free survival (PFS) and overall survival (OS), were analyzed retrospectively.

RESULTS

A total of 104 patients were included in this study. Patients with pleural effusion at initial diagnosis had significantly shorter PFS and OS than those without pleural effusion (median PFS: 8.2 months vs 15.3 months, P = 0.0004; median OS: 16.3 months vs 28.2 months, P = 0.0003). Univariate analysis revealed that being male or a smoker was associated with short PFS, whereas smoking history, bony metastasis and malignant pleural effusion were associated with poor OS. Stepwise multivariate Cox regression analysis showed that the presence of pleural effusion and different TKI use were independent prognostic factors for PFS [hazard ratio [HR] = 2.50 (95% confidence interval [CI], 1.53-4.10), P = 0.0003 and HR = 0.55 (95% CI, 0.31-0.97), P = 0.0396, respectively], whereas the presence of pleural effusion and liver metastasis were associated with poor OS [HR = 2.79 (95% CI: 1.46-5.30), P = 0.0018 and HR = 2.12 (95% CI, 1.02-4.40), P = 0.0440, respectively].

CONCLUSION

The presence of pleural effusion predicts poor PFS and OS in lung adenocarcinoma patients receiving TKIs as the first-line treatment. Additional studies are warranted to elucidate the underlying mechanisms and determine novel strategies for improving the outcome of these patients.

Systemic treatment of non-small cell lung cancer brain metastases

In the systemic treatment of brain metastases from non-small cell lung cancer (BMF-NSCLC) chemo- and targeted therapy are used. Response rates after platinum-based chemotherapy, range from 23% to 45%. Development of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs): gefitinib or erlotinib, was an improvement in treatment of advanced NSCLC patients. EGFR mutations are present in 10-25% of NSCLC (mostly adenocarcinoma), and up to 55% in never-smoking women of East Asian descent. In the non-selected group of patients with BMF-NSCLC, the overall response rates after gefitinib or erlotinib treatment range from 10% to 38%, and the duration of response ranges from 9 to 13.5 months. In the case of present activating EGFR mutation, the response rate after EGRF-TKIs is greater than 50%, and in selected groups (adenocarcinoma, patients of Asian descent, never-smokers, asymptomatic BMF-NSCLC) even 70%. Gefitinib or erlotinib treatment improves survival of BMF-NSCLC patients with EGFR mutation in comparison to cases without the presence of this mutation. There is no data on the activity of the anti-EML4-ALK agent crizotinib. Bevacizumab, recombinant humanised monoclonal antibody anti-VEGF, in the treatment of advanced non-squamous NSCLC patients is a subject of intense research. Data from a clinical trial enrolling patients with pretreated or occult BMF-NSCLC proved that the addition of bevacizumab to various chemotherapy agents or erlotinib is a safe and efficient treatment, associated with a low incidence of CSN haemorrhages. However, the efficacy and safety of bevacizumab used for therapeutic intent, regarding active brain metastases is unknown.

Epidermal growth factor receptor tyrosine kinase inhibitors for the treatment of central nervous system metastases from non-small cell lung cancer: the present and the future

Lung cancer is one of the major causes of cancer related mortality worldwide. Brain metastases (BM) complicate clinical evolution of non-small cell lung cancer (NSCLC) in approximately 25-40% of cases, adversely influencing quality of life (QoL) and overall survival (OS). Systemic therapy remains the standard strategy for metastatic disease. Nevertheless, the blood-brain barrier (BBB) makes central nervous system (CNS) a sanctuary site. To date, the combination of chemotherapy with whole brain radiation therapy (WBRT), surgery and/or stereotactic radiosurgery (SRS) represents the most used treatment for patients (pts) with intracranial involvement. However, due to their clinical conditions, many pts are not able to undergo local treatments. Targeted therapies directed against epidermal growth factor receptor (EGFR), such as gefitinib, erlotinib and afatinib, achieved important improvements in EGFR mutated NSCLC with favorable toxicity profile. Although their role is not well defined, the reported objective response rate (ORR) and the good tolerance make EGFR-tyrosine kinase inhibitors (TKIs) an interesting valid alternative for NSCLC pts with BM, especially for those harboring EGFR mutations. Furthermore, new-generation TKIs, such as osimertinib and rociletinib, have already shown important activity on intracranial disease and several trials are still ongoing to evaluate their efficacy. In this review we want to highlight literature data about the use and the effectiveness of EGFR-TKIs in pts with BM from NSCLC.

High efficacy of third generation EGFR inhibitor AZD9291 in a leptomeningeal carcinomatosis model with EGFR-mutant lung cancer cells

Leptomeningeal carcinomatosis (LMC) remarkably decreases the quality of life of EGFR-mutant lung cancer patients. In contrast to the lesions outside the central nervous system (CNS), molecular mechanisms of EGFR tyrosine kinase inhibitor (TKI) resistance in CNS lesions including LMC are largely unknown. In this study, we established an in vivo imaging model for LMC with EGFR mutant lung cancer cell lines harboring an exon 19 deletion in EGFR and evaluated the effect of first generation EGFR-TKIs, erlotinib, second generation afatinib, and third generation AZD9291. In PC-9/ffluc model, erlotinib treatment slowed the development of LMC. Importantly, treatment with afatinib or AZD9291 apparently delayed the development of LMC. Moreover, treatment with a higher dose of AZD9291, also associated with inhibited phosphorylation of EGFR downstream molecule S6, regressed LMC refractory to the aforementioned EGFR-TKI treatments. These observations suggest that the third generation EGFR-TKI AZD9291 may be an effective treatment for first or second generation EGFR-TKI resistant LMC caused by EGFR-mutant lung cancer.

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

Background

Epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKIs) are remarkably effective for treating EGFR‐mutant non‐small cell lung cancer (NSCLC). However, the individual role of EGFR‐TKIs in patients with brain metastasis (BM) arising from EGFR‐mutant NSCLC remains unclear.

Methods

Patients with BM secondary to NSCLC and harboring EGFR‐activating mutations were retrospectively screened. Patients who received gefitinib or erlotinib to control both extracranial lesions (ECLs) and intracranial lesions (ICLs) were eligible. If ECLs remained stable or remissive while ICLs progressed; asymptomatic BM progressed to symptomatic BM; BM symptoms were not alleviated within two weeks; or BM symptoms deteriorated after initial release, patients received brain radiotherapy or other local treatments and continued taking TKIs until ECLs progression occurred.

Results

In 43 eligible patients, the objective response and disease control rates for ICLs were 57% and 91%, respectively. Median progression‐free survival (PFS) was 9.3 months. The median PFS for ICLs and ECLs was 9.7 and 13.7 months, respectively. Non‐smokers and second‐line TKIs were found to be independent positive prognostic factors for PFS and overall survival (OS) respectively, with a hazard ratio of 0.29 (95% confidence interval [CI] 0.14–0.61; P = 0.001) and 0.34 (95% CI 0.16–0.70; P = 0.003). No significant difference in median OS was observed between patients who did or did not receive brain radiotherapy (23.6 vs. 18.7 months; P = 0.317).

Conclusion

EGFR‐TKIs alone are effective for treating BM arising from EGFR‐mutant NSCLC. The efficacy of TKIs in ICLs and ECLs should be evaluated separately.

[Research Progress of EGFR-TKI Therapy for Patients with Central Nervous System Metastases from Non-small Cell Lung Cancer]

Approximately half of all patients with non-small cell lung cancer (NSCLC) develop central nervous system metastases during the course of their disease which indicate poor prognosis. A part of NSCLC patients demonstrates activating epidermal growth factor receptor gene (EGFR) mutations who represent effectiveness and well tolerance of EGFR-specific tyrosine kinase inhibitors (TKIs) therapy. Although the systemic efficacy of targeted agents is established, the efficacy of central nervous system (CNS) metastases is not as well characterized. In this article, we review recent data on the use of EGFR inhibitors for treatment of patients with NSCLC and CNS metastases.

The role of EGFR-TKI for leptomeningeal metastases from non-small cell lung cancer

Leptomeningeal metastasis (LM) is a terminal event in the development of non-small cell lung cancer (NSCLC). It has a poor prognosis with median survival of 1.9 months if untreated. The improvement of OS in NSCLC patients relatively increases incidence of LM. While current therapeutic options for LM are limited. Epidermal growth factor receptor-tyrosine kinase inhibitors are a class of small molecules and show dramatic response in epidermal growth factor receptor mutated patients. It also has a distinct therapeutic potential against brain metastases. Although there are some studies on EGFR-TKIs and brain metastases, the role of EGFR-TKIs on LM are not fully clarified. In this review, we will summarize current evidences concerning the use and discuss the role of EGFR-TKIs on LM.

Recursive Partitioning Analysis of Prognostic Factors for Patients with Four or More Intracranial Metastases Treated with Radiosurgery

The purpose of this study was to devise a new recursive partitioning analysis (RPA) of patients with four or more intracranial metastases treated with a single radiosurgery procedure to identify a class of patients with extended survival. 205 patients underwent Gamma Knife radiosurgery for four or more intracranial metastases (median = 5, range 4–18) during one session. The median total treatment volume was 6.8 cc (range 0.6–51.0 cc). Radiosurgery was used as sole management (17% of patients), or in combination with WB-RT (46%), or after failure of WB-RT (38%). The median marginal radiosurgery dose was 16 Gy (range 12–20 Gy). RPA assessed the effects of age, Karnofsky >70, extracranial disease, visceral metastases, number of metastases, total treatment volume, history of breast and melanoma primaries on survival. The median overall survival after radiosurgery for all patients was 8 months. RPA identified a favorable subgroup of 78 patients (43% of the series) with a total treatment volume <7 cc and < 7 brain metastases (Class 1), with a median survival of 13 months. This subgroup's survival was significantly better (p <0.00005) than the remaining patients (Class 2) (n=111) with a median survival of 6 months. In conclusion, RPA of multiple brain metastasis patients identified 2 distinct cohorts of patients. Class 1 patients have a total treatment volume <7 cc and < 7 metastases (4–6) with favorable survival after Radiosurgery and Class 2 patients have a total treatment volume ≥ 7 cc and/or ≥ 7 metastases and have a significantly poorer survival.

Blood-brain barrier permeability of gefitinib in patients with brain metastases from non-small-cell lung cancer before and during whole brain radiation therapy

INTRODUCTION

To explore the ability of gefitinib to penetrate blood brain barrier (BBB) during whole brain radiation therapy (WBRT).

PATIENTS AND METHODS

Enrolled in this study were eligible patients who were diagnosed with BM from NSCLC. Gefitinib was given at 250 mg/day for 30 days, then concurrently with WBRT (40 Gy/20 F/4 w), followed by maintenance. Serial CSF and blood samples were collected on 30 day after gefitinib administration, and at the time of 10, 20, 30 and 40 Gy following WBRT. CSF and plasma samples of 13 patients without BM who were treated with gefitinib were collected as control. CSF and plasma gefitinib levels were measured by LC-MS/MS.

RESULTS

Fifteen BM patients completed gefitinib plus WBRT. The CSF-to-plasma ratio of gefitinib in patients with BM was higher than that in patients without BM (1.34% vs. 0.36%, P < 0.001). The CSF-to-plasma ratio of gefitinib increased with the increased dose of WBRT and reached the peak (1.87 ± 0.72%) at 30 Gy, which was significantly higher than that 1.34 ± 0.49% at 0 Gy (P = 0.01). The median time to progression of brain lesions and the median overall survival were 7.07 and 15.4 months, respectively.

CONCLUSION

The BBB permeability of gefitinib increased in accordance with escalated dose of WBRT.

Efficacy and safety of icotinib in patients with brain metastases from lung adenocarcinoma

OBJECTIVE

The objective of this study was to evaluate the efficacy and safety of icotinib in patients with brain metastases (BMs) from lung adenocarcinoma.

PATIENTS AND METHODS

Clinical data of 28 cases with BMs from lung adenocarcinoma were retrospectively analyzed. All the patients took 125 mg icotinib orally three times a day. Progression of disease, intolerable adverse reactions, and number of deaths were recorded.

RESULTS

For all the patients, the remission rate of icotinib was 67.8% and the disease control rate was 96.4%. The median overall survival time of patients was 21.2 months, and the median progression-free survival time of patients was 10.9 months. Only mild adverse events of grade 1/2 were observed during the treatment.

CONCLUSION

Icotinib was an effective and safe strategy to treat patients with BMs from lung adenocarcinoma.

Comparison of erlotinib and pemetrexed as second-/third-line treatment for lung adenocarcinoma patients with asymptomatic brain metastases

Objective

Brain metastases occur in one-third of all non-small-cell lung cancer patients. Due to restrictive transport at the blood–brain barrier, many drugs provide poor control of metastases in the brain. The aim of this study was to compare erlotinib with pemetrexed as second-/third-line treatment in patients with lung adenocarcinoma with asymptomatic brain metastases.

Methods

From January 2012 to June 2014, all lung adenocarcinoma patients with asymptomatic brain metastases who received treatment with erlotinib or pemetrexed as second-/third-line treatment were retrospectively reviewed. Chi-square and log-rank tests were used to perform statistical analysis.

Results

The study enrolled 99 patients, of which 44 were positive for EGFR mutation. Median progression-free survival (PFS) in months was not significantly different between the erlotinib- and pemetrexed-treated groups (4.2 vs 3.4 months; 95% confidence interval [CI]: 2.01–6.40 vs 2.80–5.00, respectively; P=0.635). Median PFS was found to be significantly longer in EGFR mutation–positive patients in the erlotinib-treated group (8.0 months; 95% CI 5.85–10.15) compared to the pemetrexed group (3.9 months; 95% CI: 1.25–6.55; P=0.032). The most common treatment-related side effect was mild-to-moderate rash and the most common drug-related side effects in the pemetrexed-group were vomiting and nausea.

Conclusion

Erlotinib and pemetrexed may be used as second-/third-line treatment in lung adenocarcinoma patients with asymptomatic brain metastases, and detection of EGFR mutation status is very important in these patients. EGFR mutation–positive lung adenocarcinoma patients with asymptomatic brain metastases showed longer PFS when treated with erlotinib as opposed to pemetrexed.

Icotinib as initial treatment in lung adenocarcinoma patients with brain metastases

Background

To evaluate the antitumor activity and toxicity of icotinib as initial treatment in lung adenocarcinoma patients with brain metastases.

Methods

Twenty‐one patients with histologically or pathologically documented brain metastatic lung cancer were administered icotinib as initial treatment from 2011 to 2015 at the Cancer Institute and Hospital, Chinese Academy of Medical Sciences. Chemotherapy response was assessed by Response Evaluation Criteria in Solid Tumors and toxicity was evaluated according to National Cancer Institute‐Common Toxicity Criteria. Icotinib was administered three times per day at a dose of 125mg.

Results

The median overall and progression‐free survival rates were 15.2 (1.2–31.5 months, 95% confidence interval [CI] 6.6–23.7 months) and 8.9 months (0.6–30.5 months, 95% CI 3.4–14.3 months), respectively. The overall response and disease control rates were 61.9% and 90.5%, respectively. Icotinib was well tolerated, and no grade 3/4 adverse events were observed. The most common grade 1/2 adverse events included acneiform eruptions (38.1%), diarrhea (19.0%), and stomatitis (9.5%).

Conclusion

Icotinib is effective and well tolerated as initial treatment in lung adenocarcinoma patients with brain metastases.

Epigenetic Profiling of H3K4Me3 Reveals Herbal Medicine Jinfukang-Induced Epigenetic Alteration Is Involved in Anti-Lung Cancer Activity

Traditional Chinese medicine Jinfukang (JFK) has been clinically used for treating lung cancer. To examine whether epigenetic modifications are involved in its anticancer activity, we performed a global profiling analysis of H3K4Me3, an epigenomic marker associated with active gene expression, in JFK-treated lung cancer cells. We identified 11,670 genes with significantly altered status of H3K4Me3 modification following JFK treatment (P < 0.05). Gene Ontology analysis indicates that these genes are involved in tumor-related pathways, including pathway in cancer, basal cell carcinoma, apoptosis, induction of programmed cell death, regulation of transcription (DNA-templated), intracellular signal transduction, and regulation of peptidase activity. In particular, we found that the levels of H3K4Me3 at the promoters of SUSD2, CCND2, BCL2A1, and TMEM158 are significantly altered in A549, NCI-H1975, NCI-H1650, and NCI-H2228 cells, when treated with JFK. Collectively, these findings provide the first evidence that the anticancer activity of JFK involves modulation of histone modification at many cancer-related gene loci.

[Clinical Experience of Gefitinib in the Treatment of 32 Lung Adenocarcinoma Patients with Brain Metastases]

背景与目的

脑转移是晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）常见的转移部位，预后欠佳。吉非替尼是一种表皮生长因子受体（epithelial growth factor receptor, EGFR）酪氨酸激酶抑制剂，用于治疗晚期NSCLC。本研究旨在探讨吉非替尼治疗肺腺癌脑转移的疗效及毒副反应。

方法

回顾性分析32例肺腺癌脑转移患者的临床资料，所有患者均口服吉非替尼250 mg Qd，直到疾病进展或发生不可耐受的毒副反应。

结果

全组32例患者的中位生存时间（median overall survival, mOS）和中位无进展生存时间（median progression-free survival, mPFS）分别为24.7个月和11.2个月，有效率（response rate, RR）和疾病控制率（disease control rate, DCR）分别为62.5%和93.8%。吉非替尼用于初治患者的mOS和mPFS分别为35.6个月和11.3个月，RR和DCR分别为75.0%和100.0%。吉非替尼用于复治患者的mOS和mPFS分别为18.6个月和6.7个月，RR和DCR分别为50.0%和83.3%。EGFR敏感性突变患者的mOS和mPFS分别为24.8个月和10.8个月，RR和DCR分别为75.0%和100.0%。EGFR突变状态不明患者的mOS和mPFS分别为35.6个月和12.3个月，RR和DCR分别为53.3%和86.7%。全组患者耐受性好，未观察到严重毒副反应。常见的毒副反应包括：皮疹15例（46.9%）、腹泻7例（21.9%）、口腔溃疡1例（3.1%）。

结论

吉非替尼对肺腺癌脑转移患者有效率较高且耐受性好，可以作为肺腺癌脑转移患者的一种治疗选择。

Gefitinib for asymptomatic brain metastasis from advanced non-small cell lung cancer: Report of a favourable outcome

Brain metastasis (BM) is common in patients with non-small cell lung cancer (NSCLC). Although epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have now been included as standard treatment options for NSCLC harboring EGFR-activating mutations, only a few prospective reports demonstrate the efficacy of these agents in a BM setting. We report a case of a patient with advanced NSCLC, in which oral gefitinib documented a significant antitumor effect on parallel progression of extracranial lesion and BM occurred during chemotherapy.

A phase I trial of high dose gefitinib for patients with leptomeningeal metastases from non-small cell lung cancer

Introduction

There are few effective treatment options for leptomeningeal metastasis (LM) in non-small-cell lung cancer (NSCLC). This study assessed the feasibility of high-dose gefitinib in patients with LM from NSCLC harboring EGFR mutations or prior systemic response to EGFR-TKI.

Methods

This phase I open-label trial of a novel gefitinib dosing schedule employed a 3+3 design. Eligible NSCLC patients with LM had known EGFR mutations and/or prior response to EGFR-TKI. Patients alternated 2 weeks of high-dose daily gefitinib (dose levels: 750 mg, 1000 mg, 1250 mg) with 2 weeks of maintenance therapy (500 mg daily). Primary endpoints were safety and toxicity. Secondary endpoints included overall survival (OS), neurological progression-free survival, radiological response, and cytological response in cerebrospinal fluid (CSF).

Results

Seven patients were treated: 3 at 750 mg dose level, 4 at 1000 mg dose level. There were no DLTs at the 750 mg dose level, and one DLT (toxic epidermal necrolysis) at the 1000 mg dose level. The study was closed due to slow accrual. Median neurological PFS was 2.3months (range 1.6–4.0 months); median OS was 3.5months (range 1.6–5.1months). Though there were no radiologically documented remissions of LM disease, four patients had improvement in neurological symptoms. One patient cleared their CSF of NSCLC cells, while 2 others had decrease in malignant cells in CSF.

Conclusion

Although the MTD was not defined due to slow accrual, this study provides important information about the tolerability and CSF penetration of high-dose gefitinib as a therapeutic option for modest palliation for NSCLC patients with LM and a known EGFR mutation.

Effects of an Epithelial Growth Factor Receptor-Tyrosine Kinase Inhibitor Add-on in Stereotactic Radiosurgery for Brain Metastases Originating from Non-Small-Cell Lung Cancer

OBJECTIVE

This study was aimed at optimizing the treatment of non-small-cell lung cancer (NSCLC) patients who are candidates for stereotactic radiosurgery (SRS) for brain metastases and harbor activating epithelial growth factor receptor (EGFR) mutations.

METHODS

We retrospectively reviewed the medical records from 2005 to 2010 of NSCLC patients with brain metastases harboring an activating EGFR mutation. Patients who received a combination therapy of SRS and EGFR-tyrosine kinase inhibitor (TKI) for brain metastases and those who received SRS without EGFR-TKI were compared. The primary endpoint was progression-free survival (PFS) of the brain metastases.

RESULTS

Thirty-one patients were eligible for enrolment in this study (SRS with TKI, 18; SRS without TKI, 13). Twenty-two patients (71.0%) were women and the median overall age was 56.0 years. PFS of brain lesions was not significantly prolonged in SRS with TKI treatment group than in SRS without TKI group (17.0 months vs. 9.0 months, p=0.45). Local tumor control rate was 83.3% in the combination therapy group, and 61.5% in the SRS monotherapy group (p=0.23). There were no severe adverse events related with treatment in both groups.

CONCLUSIONS

Therapeutic outcome of concurrent SRS and TKI treatment was not superior to SRS monotherapy, however, there was no additive adverse events related with combined treatment.

Current Status of CTCs as Liquid Biopsy in Lung Cancer and Future Directions

Circulating tumor cells (CTCs) have garnered a lot of attention in the past few decades. Isolation of these rare cells from the billions of blood cells has been a challenge until recent times. With the advent of new sensitive technologies that permit live cell isolation and downstream genomic analysis, the existing paradigm of CTC research has evolved to explore clinical utility of these cells. CTCs have been identified as prognostic and pharmacodynamic biomarkers in many solid tumors, including lung cancer. As a means of liquid biopsy, CTCs could play a major role in the development of personalized medicine and targeted therapies. This review discusses the state of various isolation strategies, cell separation techniques and key studies that illustrate the application of liquid biopsy to lung cancer.

A phase II study of icotinib and whole-brain radiotherapy in Chinese patients with brain metastases from non-small cell lung cancer

PURPOSE

Icotinib is a new first-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. A phase II study was conducted to evaluate the efficacy and safety of icotinib in combination with whole-brain radiotherapy (WBRT) in Chinese NSCLC patients with brain metastases (BMs); the cerebrospinal fluid (CSF)/plasma concentrations of icotinib were also investigated.

METHODS

Eligible patients had BMs from NSCLC, regardless of the EGFR status. Icotinib was administered at 125 mg orally 3 times/day until tumor progression or unacceptable toxicity, concurrently with WBRT (3.0 Gy per day, 5 days per week, to 30 Gy). CSF and plasma samples were collected simultaneously from 10 patients. Icotinib concentrations in the CSF and plasma were measured by high-performance liquid chromatography coupled with tandem mass spectrometry.

RESULTS

Twenty patients were enrolled. The median follow-up time was 20.0 months. The overall response rate was 80.0%. The median progression-free survival time was 7.0 months (95% CI 1.2-13.2 months), and the median survival time (MST) was 14.6 months (95% CI 12.5-16.7 months). Of the 18 patients with known EGFR status, the MST was 22.0 months for those with an EGFR mutation and was 7.5 months for those with wild-type EGFR (P = 0.0001). The CSF concentration and penetration rate of icotinib were 11.6 ± 9.1 ng/mL and 1.4 ± 1.1%, respectively. No patient experienced ≥grade 4 toxicity.

CONCLUSIONS

Icotinib was well tolerated in combination with WBRT and showed efficacy in patients with BMs from NSCLC. This clinical benefit was related to the presence of activating EGFR mutations.

Molecular determinants of lung cancer metastasis to the central nervous system

Lung cancer remains the leading cause of cancer-related mortality worldwide. The propensity for metastasis to the central nervous system (CNS) is a major clinical hurdle contributing to the low five-year survival rate of advanced disease. CNS metastases significantly outnumber primary brain tumors and carry a dismal prognosis in part due to the inability of therapeutic agents to cross the blood brain barrier. Standard treatment using radiation has been largely ineffective in improving mortality, suggesting the need for new agents targeting the critical metastatic drivers. The genetic and molecular events governing CNS metastasis from the lung are poorly understood at this time. This review highlights genetic events associated with CNS dissemination from the lung and molecular mechanisms associated with CNS metastasis. In vivo model systems that faithfully recapitulate escape from the lung and colonization of the CNS are described as tools for understanding the metastatic phenotype and for testing new therapeutic agents. A deeper understanding of the mechanisms of lung cancer metastasis to the CNS is needed to elucidate novel therapeutic avenues towards the improvement of the mortality associated with advanced stage lung cancer.

Considerations on the management of EGF receptor-TKIs for brain metastases in EGFR-mutant lung carcinoma patients

SUMMARY 

Approximately 20–30% of patients with NSCLC are present with brain metastases. The standard management for brain metastases is radiotherapy. Despite the administration of radiation therapy for brain metastases, the prognosis is still poor. The poor prognosis is related to the progression of extracranial lesions. Therefore, systemic therapy is important to improve survival of patients with brain metastases. EGF receptor-tyrosine kinase inhibitor (EGFR-TKI) is a standard treatment for advanced NSCLC patients with sensitive EGFR mutations and is also effective in controlling brain metastasis in such patients. Upfront EGFR-TKI therapy might be one of the treatment choices for EGFR-mutant NSCLC patients with asymptomatic brain metastases. However, it is unclear whether upfront EGFR-TKI or radiation therapy is more preferable. New EGFR-TKIs and combination with existing EGFR-TKIs and other drugs are being investigated for treatment options. Further investigations are required to determine the future direction for management of EGFR-mutant NSCLC patients with brain metastasis.

[Research progress of targeted therapy in non-small cell lung cancer brain metastases]

Lung cancer is characterized by the highest incidence of solid tumor-related brain metastases, which are reported the incidence ranged 20% to 65%. This is also one of the reasons why it can cause significant mortality. Molecular targeted therapy plays a major role in the management of brain metastases in lung cancer. Targeted agents have become the novel methods for the treatment of lung cancer with brain metastases beyond the whole brain radiation therapy, stereotactic radiosurgery and chemotherapy. Recently, more and more studies and trials laid emphasis on the targeted agents for non-small cell lung cancer (NSCLC) brain metastases treatment. The key point is the efficacy and safety. In this paper, the targeted treatments of NSCLC brain metastases were summarized.

EGFR-TKI therapy for patients with brain metastases from non-small-cell lung cancer: a pooled analysis of published data

Introduction

Brain metastases are one of the leading causes of death from non-small-cell lung cancer (NSCLC). The use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) to treat brain metastases remains controversial. Thus, we performed a pooled analysis of published data to evaluate the efficacy of EGFR-TKIs in NSCLC patients with brain metastases, particularly for tumors with activating EGFR mutations.

Methods

Several data sources were searched, including PubMed, Web of Science, and ASCO Annual Meetings databases. The end points were intracranial overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events. The pooled ORR, DCR, PFS, and OS with 95% confidence intervals (CIs) were calculated employing fixed- or random-effect models, depending on the heterogeneity of the included studies.

Results

Sixteen published studies were included in this analysis, with a total of 464 enrolled patients. The EGFR mutational status was unknown for 362 (unselected group), and 102 had activating EGFR mutations. The pooled intracranial ORR and DCR were 51.8% (95% CI: 45.8%–57.8%) and 75.7% (95% CI: 70.3%–80.5%), respectively. A higher ORR was observed in the EGFR mutation group than in the unselected group (85.0% vs 45.1%); a similar trend was observed for the DCR (94.6% vs 71.3%). The pooled median PFS and OS were 7.4 months (95% CI, 4.9–9.9) and 11.9 months (95% CI, 7.7–16.2), respectively, with longer PFS (12.3 months vs 5.9 months) and OS (16.2 months vs 10.3 months) in the EGFR mutation group than in the unselected group.

Conclusion

This pooled analysis strongly suggests that EGFR-TKIs are an effective treatment for NSCLC patients with brain metastases, particularly in those patients harboring EGFR mutations. Larger prospective randomized clinical trials are warranted to confirm our conclusion and identify the most appropriate treatment model.

A comparative analysis of EGFR mutation status in association with the efficacy of TKI in combination with WBRT/SRS/surgery plus chemotherapy in brain metastasis from non-small cell lung cancer

We proposed to identify the efficacy of an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) using whole brain radiotherapy (WBRT)/stereotactic radiosurgery (SRS)/surgery in brain metastases from patients with non-small cell lung cancer (NSCLC) and clarify the association between treatment outcome and EGFR gene mutation status. A total of 282 patients with NSCLC brain metastases who underwent WBRT/SRS/surgery alone or in combination with TKI were enrolled in our study from 2003-2013. Amplification mutation refractory system technology was used to determine the EGFR mutation status in 109 tissue samples. EGFR mutation detection was performed in 109 patients with tumor tissues. The EGFR positive rate was 50 % (55/109), including 26 exon 19 deletions and 24 L858R mutations. The median follow-up time was 28 months. The median overall survival, median progression-free survival of intracranial disease, and median progression-free survival of extracranial disease was significantly longer for patients with TKI treatment (31.9 vs 17.0 months, P < 0.0001; 19.8 vs 12.0 months, P < 0.0001; and 19.6 vs 12.3 months, P < 0.0001; respectively). In subgroup analysis within the TKI group, patients harboring EGFR mutations had better extracranial disease control (20.4 vs 14.1 months, P = 0.032). Administration of TKI agents with conventional therapy compared with conventional therapy alone might be beneficial for overall survival, progression-free survival of intracranial disease and progression-free survival of extracranial disease in patients with brain metastases from NSCLC independent of EGFR mutations.

Favorable response to icotinib in a lung cancer patient with a special mutation at exon 19 of epidermal growth factor receptor

Many studies have illustrated that two types of mutation - deletions in exon 19 and a point mutation in exon 21 (L858R) - have been reported to comprise up to 90% of all activating epidermal growth factor receptor (EGFR) mutations. A point mutation at exon 19 is a rare mutation, and to date there have been no reports investigating the sensitivities of EGFR-tyrosine kinase inhibitors (TKIs) to the mutation. In this case report, we have demonstrated a special mutation, a point mutation at c.2279T>C (p.L760P) in exon 19 of EGFR, which has responded favorably to icotinib in a lung adenocarcinoma patient with brain metastasis. Icotinib is a new type of oral EGFR-TKI developed in China and is the first EGFR-TKI in Asia. Icotinib has the potential to improve the prognosis of lung adenocarcinoma patients and with less toxic-effect.

Epidermal growth factor receptor tyrosine kinase inhibitors in the treatment of central nerve system metastases from non-small cell lung cancer

Brain metastases (BM) are common and disastrous occurrence in patients with non-small cell lung cancer (NSCLC). Currently increasing studies suggest remarkable efficacy and mild toxicity of the epidermal growth factor tyrosine kinase inhibitor (EGFR TKI) in these patients, making targeted therapy an attractive option to BM from NSCLC. We here present a review about the use of EGFR-TKIs in this context and the following questions would be discussed: Are TKIs capable of permeating across brain-blood barrier (BBB)? How to boost exposure of EGFR TKI in cerebrospinal fluid to overcome the resistance of refractory metastases? Would the combination with other treatment like radiotherapy bring about advanced effect? And which patients with BM is the fittest population to EGFR-TKI treatment? In fact, though the administration of EGFR TKI only could achieve certain effect with limited penetration across BBB, increasing dose and combined radiotherapy would carry out better outcome. Unsurprisingly EGFR mutations were still the most important predictor of the sensitivity.