EGFR mutation status and survival after diagnosis of brain metastasis in nonsmall cell lung cancer

[Optimal therapeutic strategy for non-small cell lung cancer with mutated epidermal growth factor receptor]

Although epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have been widely used in non-small cell lung cancer (NSCLC) patients, it is still controversial about how to combine EGFR-TKI with chemotherapy and other targeted drugs. We have made a summary on the current therapeutic models of EGFR-TKI combined with chemotherapy/bevacizumab in this review and aimed to find the optimal therapeutic strategy for NSCLC patients with EGFR mutation.

EGFR tyrosine kinase inhibitors versus cranial radiation therapy for EGFR mutant non-small cell lung cancer with brain metastases: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

EGFR TKIs alone have demonstrated activity against intracranial disease in EGFR mutant non-small cell lung cancer (NSCLC). This study aimed to determine if upfront cranial radiotherapy improves intracranial disease control and survival outcomes in EGFR mutant NSCLC with brain metastases relative to TKIs alone.

MATERIALS AND METHODS

We searched MEDLINE and various conference proceedings from 2008 to July 2014 for eligible studies where patients received upfront cranial radiotherapy or TKIs alone. Outcomes of interest were overall intracranial disease response rate (ORR), four-month intracranial disease progression-free survival (PFS), two-year overall survival (OS) and neurological adverse events (AE). We used random effects models to pool outcomes across studies and compared them using interaction tests.

RESULTS

We found 12 non-comparative observational studies (n=363) with severe methodological limitations. Upfront cranial radiotherapy results in similar intracranial disease ORR (relative risk (RR) 0.93, 95% confidence interval (CI) 0.82-1.06; interaction p value (p)=0.53), improved four-month intracranial disease PFS (RR 1.06, 95% CI 1.00-1.12; p=0.03), improved two-year OS (RR 1.33, 95% CI 1.00-1.77; p=0.05) but caused more neurological AEs than TKIs alone.

CONCLUSION

There is evidence, albeit of low quality, that upfront cranial radiotherapy may improve intracranial disease control and survival outcomes compared with TKI alone.

Prognostic significance of EGFR and KRAS mutations in NSCLC patients with brain metastases treated with radiosurgery†

PURPOSE

Determine whether EGFR and KRAS mutations carry prognostic significance in non-small cell lung cancer (NSCLC) patients with brain metastases treated with stereotactic radiosurgery.

METHODS AND MATERIALS

Ninety-four NSCLC patients with brain metastases initially treated with stereotactic radiosurgery were retrospectively reviewed. Both EGFR and KRAS mutation status were recorded in 67 patients: EGFR+/KRAS- status in 9 patients, EGFR-/KRAS+ in 15 patients, and EGFR-/KRAS- in 43 patients. Survival was determined using the Kaplan-Meier method. Cox regression was used to assess the effects of patient factors on overall survival, local control, and distant brain control - all from time of brain metastasis diagnosis.

RESULTS

Median overall survival from time of brain metastasis diagnosis was 30.6 months for EGFR+/KRAS- patients, 9.8 months for EGFR-/KRAS+ patients, and 19.1 months for EGFR-/KRAS- patients (p=0.094). Local control at 2 years was 100% for EGFR+/KRAS- patients, 66.7% for EGFR-/KRAS+ patients, and 97.2% for EGFR-/KRAS- patients (p=0.399). Distant brain control at 12 months was achieved in 66.7% of EGFR+/KRAS- patients, 30.0% of EGFR-/KRAS+ patients, and 73.7% of EGFR-/KRAS- patients (p=0.039). On multivariate analysis, the most important predictors of mortality were baseline DS-GPA>2 (HR=0.27; p=0.001), EGFR mutation positivity (HR=0.30; p=0.054), and KRAS mutation positivity (HR=2.12; p=0.056); the most important predictors of distant brain failure were KRAS status (HR=4.44; p=0.004) and extracranial disease (HR=3.28; p=0.058); there was no statistically significant multivariate model identified for local control.

CONCLUSIONS

In NSCLC patients with brain metastases, KRAS mutations portend higher rates of distant brain failure. Our data also suggests that EGFR portends better overall survival and KRAS portends worse overall survival, though this still needs to be verified by a larger study.

Efficacy of the irreversible ErbB family blocker afatinib in epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-pretreated non-small-cell lung cancer patients with brain metastases or leptomeningeal disease

INTRODUCTION

Afatinib is an effective first-line treatment in patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) and has shown activity in patients progressing on EGFR-tyrosine kinase inhibitors (TKIs). First-line afatinib is also effective in patients with central nervous system (CNS) metastasis. Here we report on outcomes of pretreated NSCLC patients with CNS metastasis who received afatinib within a compassionate use program.

METHODS

Patients with NSCLC progressing after at least one line of chemotherapy and one line of EGFR-TKI treatment received afatinib. Medical history, patient demographics, EGFR mutational status, and adverse events including tumor progression were documented.

RESULTS

From 2010 to 2013, 573 patients were enrolled and 541 treated with afatinib. One hundred patients (66% female; median age, 60 years) had brain metastases and/or leptomeningeal disease with 74% having documented EGFR mutation. Median time to treatment failure for patients with CNS metastasis was 3.6 months, and did not differ from a matched group of 100 patients without CNS metastasis. Thirty-five percent (11 of 31) of evaluable patients had a cerebral response, five (16%) responded exclusively in brain. Response duration (range) was 120 (21-395) days. Sixty-six percent (21 of 32) of patients had cerebral disease control on afatinib. Data from one patient with an impressive response showed an afatinib concentration in the cerebrospinal fluid of nearly 1 nMol.

CONCLUSION

Afatinib appears to penetrate into the CNS with concentrations high enough to have clinical effect on CNS metastases. Afatinib may therefore be an effective treatment for heavily pretreated patients with EGFR-mutated or EGFR-TKI-sensitive NSCLC and CNS metastasis.

An active treatment of lung adenocarcinoma cancer with brain metastases: icotinib

Lung cancer has the highest mortality rate of all cancers worldwide. A total of 70%-75% of all lung cancers are non-small cell lung cancer (NSCLC) with two-thirds presenting with locally advanced or metastatic disease at diagnosis. Brain metastasis is one of the most common problems in the management of NSCLC, worsening the prognosis and quality of life of NSCLC patients. The epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) gefitinib and erlotinib have been tested in patients with NSCLC and brain metastasis. Icotinib is a new type of oral EGFR-TKI. In this report, we describe a patient with lung adenocarcinoma cancer with brain metastases who received icotinib treatment and kept satisfactory health-related quality of life for 1 year.

Analysis of prognostic factors and comparison of prognostic index scores in patients with brain metastases after whole-brain radiotherapy

BACKGROUND AND PURPOSE

Brain metastases (BMs) are typically associated with poor patient prognosis. Radiation therapy remains the primary treatment for BMs, and patient's prognosis is affected by many factors. The aim of this study was to identify prognostic factors and to compare prognostic index scores in patients with BMs who received whole-brain radiotherapy (WBRT).

METHODS

A retrospective prognostic study was conducted in 125 patients with BMs who underwent WBRT between Jan 2008 and Jul 2011. The significance of prognostic variables with regard to survival was determined using univariate and multivariate analyses. A prognostic index (PI) was established based on Cox regression analysis and subgrouping values. The recursive partitioning analysis classes (RPA), basic score for brain metastases (BS-BM), Graded Prognostic Assessment index (GPA), and PI were assessed with regard to prognosis.

RESULTS

The median survival time was 213 days (7.1 months). In the univariate analysis of the test group, survival was significantly associated with Karnofsky performance status (KPS) score, the number of BMs, the presence of extracranial metastases, primary tumor status and the number of involved extracranial organs. The multivariate analysis showed that the KPS score (P = 0.002, Wald = 9.700), presence of extracranial metastases (P = 0.018, Wald = 5.604) and primary tumor status (P = 0.001, Wald = 10.212) were significantly correlated with overall survival. RPA, BS-BM and GPA were all closely related to prognosis, as determined using a log-rank test. In predicting the 3- and 6-month survival for patients, the PI was superior to the other three modes.

CONCLUSIONS

The three indexes, RPA, BS-BM and GPA, are valid prognostic index models; however, the PI model was the most powerful.

Value of oncogenes for the prediction of brain metastases at initial diagnosis: a review of published data

Identifying cancer patients who are at high risk of developing brain metastases at initial diagnosis and applying effective intervention or monitoring strategies is of vital importance. Recent advances in the biology of brain metastases revealed that some oncogenes from primary tumors may be potential markers for identifying cancer patients likely to metastasize to the brain. We here summarize data on the mechanisms of brain metastases supporting the involvement of oncogene changes in the brain metastatic evolution. We also review the available evidence on clinical studies of oncogenes in the prediction of cancer patients with high incidence of brain metastases.

The Importance of Brain Metastasis in EGFR Mutation Positive NSCLC Patients

Introduction. Brain metastasis is a poor prognostic marker in lung cancer. However it is not known whether amongst patients with EGFR mutation those with brain metastases have a worse outcome. Methods. We compared the survival outcomes between EGFR mutation positive patients with and without brain metastases. In this retrospective analysis of prospective database of all metastatic lung cancer patients at our centre between July 2009 and December 2012, patients were treated with either combination chemotherapy or oral TKI. All patients with brain metastases received whole brain radiation. Kaplan Meier method was used for survival analysis and compared using log rank test. Results. 101 patients with EGFR mutated, metastatic lung cancer were studied. Fourteen had brain metastases and 87 did not. The common EGFR mutations were exon 19 deletion (61.3%) and exon 21 L858R mutation (28.7%). Overall response was 64% in extracranial metastasis group as compared to 50% in brain metastasis group. There was a significant worsening of median OS in the patients with brain metastases (11.6 months) compared with only extracranial metastases (18.7 months), P = 0.029. Conclusion. Amongst patients with EGFR mutant NSCLC, the presence of brain metastases leads to a worse outcome as compared to patients with extracranial metastases alone.

Additional prognostic role of EGFR activating mutations in lung adenocarcinoma patients with brain metastasis: integrating with lung specific GPA score

OBJECTIVE

While several prognostic models have been presented in NSCLC patients with brain metastasis, none of these models have included molecular markers as an index. The aim of our study was to evaluate the prognostic value of EGFR mutations and to integrate these EGFR mutations into the prognostic index in NSCLC patients with brain metastasis.

MATERIALS AND METHODS

We analyzed retrospectively 292 lung adenocarcinoma patients with brain metastasis. Clinico-pathological features and overall survival (OS) were compared between patients with EGFR mutations and patients with EGFR wild type. EGFR mutation status was integrated with lung specific graded prognostic assessment (GPA) score.

RESULTS

Among 292 patients, EGFR mutation status was tested in 183 patients. One hundred and five patients (57.4%) had EGFR activating mutations, 14 (7.7%) had EGFR non-activating mutations and 64 (35.0%) had EGFR wild type. OS was significantly longer in patients with EGFR activating mutations than in those with EGFR wild type patients (20.4 vs. 10.1 months, p = 0.002). However, patients with EGFR non-activating mutations did not show superior OS compared with EGFR wild type patients (14.6 vs. 10.1 months, p = 0.83). Multivariate analysis revealed that the presence of EGFR activating mutation is an independent positive prognostic factor for OS (adjusted hazard ratio 0.56, p = 0.002).

CONCLUSIONS

EGFR activating mutations have a prognostic role in lung adenocarcinoma patients with brain metastasis that is independent of other known prognostic factors. The frequency of EGFR mutation was higher than expected. The presence of EGFR activating mutations should be included as an index in the prognostic models for lung adenocarcinoma patients with brain metastasis.

The management of brain metastases in non-small cell lung cancer

Brain metastases (BM) are a common and lethal complication of non-small cell lung cancer (NSCLC), which portend a poor prognosis. In addition, their management implies several challenges including preservation of neurological and neurocognitive function during surgery or radiation-therapy, minimizing iatrogenic complications of supportive medications, and optimizing drug delivery across the blood–brain barrier. Despite these challenges, advancements in combined modality approaches can deliver hope of improved overall survival and quality of life for a subset of NSCLC patients with BM. Moreover, new drugs harnessing our greater understanding of tumor biology promise to build on this hope. In this mini-review, we revised the management of BM in NSCLC including advancements in neurosurgery, radiation therapy, as well as systemic and supportive therapy.

Prognostic factors for brain metastases from non-small cell lung cancer with EGFR mutation: influence of stable extracranial disease and erlotinib therapy

The aim of this study was to explore prognostic factors for non-small cell lung cancer (NSCLC) patients with brain metastases (BM) on the basis of EGFR mutation status. Among 779 consecutive NSCLC patients who underwent EGFR mutation screening, all 197 patients with BM were divided according to the EGFR mutation status. The prognostic factors, including patient characteristics at the time of BM diagnosis, treatment history, and radiologic features, were analyzed. Of 197 patients with BM, 108 had wild-type EGFR and 89 had EGFR mutation. The patients with EGFR mutation presented longer overall survival after BM diagnosis (OS) than those with wild-type EGFR, regardless of whether BM was synchronous or metachronous. For the patients with EGFR mutation, favorable prognostic factors in multivariate analysis were age<65 (p=0.037), good performance status (PS) (p<0.0001), cranial radiotherapy (p=0.020), previous chemotherapy≤1 regimen (p=0.009), stable extracranial disease at BM diagnosis (p=0.022), and erlotinib therapy after BM diagnosis (p=0.0015). On the other hand, favorable prognostic factors for the patients with wild-type EGFR were only good PS (p=0.0037) and cranial radiotherapy (p=0.0005). Among patients treated with erlotinib after BM diagnosis, the patients with exon 19 deletion showed longer OS than those with exon 21 point mutation (p=0.019). The prognostic factors for NSCLC patients with BM were different according to the EGFR mutation status. Particularly in NSCLC patients with EGFR mutation and stable extracranial disease, regular cranial evaluation for detecting asymptomatic BM would lead to good prognosis. In addition, erlotinib therapy would be preferable in NSCLC patients with BM and EGFR mutation, especially those with exon 19 deletion.

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.

Significance of targeted therapy and genetic alterations in EGFR, ALK, or KRAS on survival in patients with non-small cell lung cancer treated with radiotherapy for brain metastases

BACKGROUND

We determined the impact of genetic alterations in EGFR, ALK, or KRAS on survival after radiotherapy for brain metastases in non-small cell lung cancer (NSCLC).

METHODS

Of 172 genotyped NSCLC patients treated with radiotherapy for brain metastases in 2005-2012, 54 had cancers with EGFR mutations, 12 had ALK rearrangements, 38 had KRAS mutations, and 68 were wild-type (WT). Overall survival (OS) was determined.

RESULTS

Median follow-up was 8.6 months. Median OS was 13.6 months for patients with EGFR mutations and 26.3 months for patients with ALK rearrangements, in contrast to 5.7 months for KRAS-mutant patients and 5.5 months for WT patients (P = .001). On multivariate analysis, adjusting for receipt of targeted therapy after cranial radiotherapy, ALK rearrangements were associated with improved OS (HR, 0.31; 95% CI, 0.13-0.74; P = .008). EGFR mutations were not significantly associated with improved OS on multivariate analysis (HR, 0.71; 95% CI, 0.37-1.38; P = .3). KRAS mutations were also not associated with improved OS (HR, 0.93; 95% CI, 0.59-1.47; P = .8). Receipt of targeted therapy after cranial radiotherapy was independently associated with improved OS (HR, 0.30; 95% CI, 0.17-0.54; P < .001). Receipt of chemotherapy after cranial radiotherapy, number of brain metastases, extracranial metastases, age, and performance status were also associated with OS.

CONCLUSIONS

NSCLC patients with genetic alterations in ALK have improved survival outcomes after radiotherapy for brain metastases compared with EGFR, KRAS, or WT. Subsequent receipt of targeted therapy was associated with additional improvement in OS.

Brain metastasis: new opportunities to tackle therapeutic resistance

Brain metastasis is a devastating complication of cancer with unmet therapeutic needs. The incidence of brain metastasis has been rising in cancer patients and its response to treatment is limited due to the singular characteristics of brain metastasis (i.e., blood-brain-barrier, immune system, stroma). Despite improvements in the treatment and control of extracranial disease, the outcomes of patients with brain metastasis remain dismal. The mechanisms that allow tumor cells to promulgate metastases to the brain remain poorly understood. Further work is required to identify the molecular alterations inherent to brain metastasis in order to identify novel therapeutic targets and explicate the mechanisms of resistance to systemic therapeutics. In this article, we review current knowledge of the unique characteristics of brain metastasis, implications in therapeutic resistance, and the possibility of developing biomarkers to rationally guide the use of targeted agents.

Whole brain radiotherapy plus simultaneous in-field boost with image guided intensity-modulated radiotherapy for brain metastases of non-small cell lung cancer

Background

Whole brain radiotherapy (WBRT) plus sequential focal radiation boost is a commonly used therapeutic strategy for patients with brain metastases. However, recent reports on WBRT plus simultaneous in-field boost (SIB) also showed promising outcomes. The objective of present study is to retrospectively evaluate the efficacy and toxicities of WBRT plus SIB with image guided intensity-modulated radiotherapy (IG-IMRT) for inoperable brain metastases of NSCLC.

Methods

Twenty-nine NSCLC patients with 87 inoperable brain metastases were included in this retrospective study. All patients received WBRT at a dose of 40 Gy/20 f, and SIB boost with IG-IMRT at a dose of 20 Gy/5 f concurrent with WBRT in the fourth week. Prior to each fraction of IG-IMRT boost, on-line positioning verification and correction were used to ensure that the set-up errors were within 2 mm by cone beam computed tomography in all patients.

Results

The one-year intracranial control rate, local brain failure rate, and distant brain failure rate were 62.9%, 13.8%, and 19.2%, respectively. The two-year intracranial control rate, local brain failure rate, and distant brain failure rate were 42.5%, 30.9%, and 36.4%, respectively. Both median intracranial progression-free survival and median survival were 10 months. Six-month, one-year, and two-year survival rates were 65.5%, 41.4%, and 13.8%, corresponding to 62.1%, 41.4%, and 10.3% of intracranial progression-free survival rates. Patients with Score Index for Radiosurgery in Brain Metastases (SIR) >5, number of intracranial lesions <3, and history of EGFR-TKI treatment had better survival. Three lesions (3.45%) demonstrated radiation necrosis after radiotherapy. Grades 2 and 3 cognitive impairment with grade 2 radiation leukoencephalopathy were observed in 4 (13.8%) and 4 (13.8%) patients. No dosimetric parameters were found to be associated with these late toxicities. Patients received EGFR-TKI treatment had higher incidence of grades 2–3 cognitive impairment with grade 2 leukoencephalopathy.

Conclusions

WBRT plus SIB with IG-IMRT is a tolerable and effective treatment for NSCLC patients with inoperable brain metastases. However, the results of present study need to be examined by the prospective investigations.

Re-evaluation of cytostatic therapies for meningiomas in vitro

PURPOSE

The purpose was to re-evaluate in cell culture models the therapeutic usefulness of some discussed chemotherapies or targeted therapies for meningiomas with a special emphasis on the role of the neurofibromatosis type 2 (NF2) tumor suppressor, which had been neglected so far. In addition, the study intended to evaluate a potential benefit from a treatment with drugs which are well established in other fields of medicine and have been linked recently with tumor disease by epidemiological studies.

METHODS

Meningioma cell lines corresponding to various subtypes and pairs of syngenic meningioma cell lines with or without shRNA-induced NF2 knockdown were analyzed for their dose-dependent response to the drugs in microtiter tetrazolium assays, BrdU assays and for selected cases in ELISAs measuring nucleosome liberation to specifically separate cell death from pure inhibition of cell proliferation.

RESULTS

We confirmed a moderate efficacy of hydroxyurea (HU) in clinically relevant concentrations. Under appropriate dosing, we neither detected major responses to the alkylating compound temozolomide nor to various drugs targeting membrane receptors or enzymes (tamoxifen, erlotinib, mifepristone, losartan, metformin and verapamil). Only concentrations far beyond achievable serum levels generated significant effects with the exception of losartan, which showed no effects at all. Chemosensitivity varied markedly among meningioma cell lines. Importantly, cells with NF2 loss exhibited a significantly higher induction of cell death by HU.

CONCLUSIONS

Alternative chemotherapeutic or targeted approaches besides HU have still to be evaluated in further studies, and the role of NF2 must be taken into account.

Brain metastases in lung adenocarcinoma: impact of EGFR mutation status on incidence and survival

Background

The brain represents a frequent progression site in lung adenocarcinoma. This study was designed to analyse the association between the epidermal growth factor receptor (EGFR) mutation status and the frequency of brain metastases (BM) and survival in routine clinical practice.

Patients and methods

We retrospectively analysed the medical records of 629 patients with adenocarcinoma in Slovenia who were tested for EGFR mutations in order to analyse the cumulative incidence of BM, the time from the diagnosis to the development of BM (TDBM), the time from BM to death (TTD) and the median survival.

Results

Out of 629 patients, 168 (27%) had BM, 90 patients already at the time of diagnosis. Additional 78 patients developed BM after a median interval of 14.3 months; 25.8 months in EGFR positive and 11.8 months in EGFR negative patients, respectively (p = 0.002). EGFR mutations were present in 47 (28%) patients with BM. The curves for cumulative incidence of BM in EGFR positive and negative patients demonstrate a trend for a higher incidence of BM in EGFR mutant patients at diagnosis (19% vs. 13%, p = 0.078), but no difference later during the course of the disease. The patients with BM at diagnosis had a statistically longer TTD (7.3 months) than patients who developed BM later (3.1 months). The TTD in EGFR positive patients with BM at diagnosis was longer than in EGFR negative patients (12.6 vs. 6.8, p = 0.005), while there was no impact of EGFR status on the TTD of patients who developed BM later.

Conclusions

Except for a non-significant increase of frequency of BM at diagnosis in EGFR positive patients, EGFR status had no influence upon the cumulative incidence of BM. EGFR positive patients had a longer time to CNS progression. While EGFR positive patients with BM at diagnosis had a longer survival, EGFR status had no influence on TTD in patients who developed BM later during the course of disease.

Features and prognostic impact of distant metastasis in patients with stage IV lung adenocarcinoma harboring EGFR mutations: importance of bone metastasis

Mutated epidermal growth factor receptor (EGFR) and signaling pathways were associated with multiple brain and intra-pulmonary metastases, oncogenic progression and metastasis. However, features of metastasis to other organs and the independent prognostic influence of metastatic lesions were not elucidated in patients with lung cancer harboring EGFR mutations. Between January 2007 and April 2012, we treated 277 patients diagnosed with stage IV lung adenocarcinoma. Studied were 246 patients with available tumor EGFR mutation data who also underwent radiographic evaluation of lung, abdominal, brain, and bone metastases. The EGFR mutated group (N = 98) had significantly more metastatic lesions in the brain and bone than the wild-type group (N = 148): brain, 3 (1-93) versus 2 (1-32) median (range), P = 0.023; bone, 3 (1-43) versus 2 (1-27), P = 0.035, respectively. In addition, EGFR mutations were significantly more frequent in patients with multiple than non-multiple lung metastases (24/40 vs. 12/42, P = 0.004). Multivariate analysis showed that bone metastasis was a significant independent negative predictive factor of overall survival (OS) in patients with mutated [hazard ratio (HR) 2.04; 95 % confidence interval (CI) 1.17-3.64; P = 0.011] and wild-type EGFR (HR 2.09; 95 % CI 1.37-3.20; P < 0.001). In conclusion, patients with mutated EGFR had more lung, brain, and bone metastases, and bone metastasis was an independent negative predictor of OS.

Erlotinib versus radiation therapy for brain metastases in patients with EGFR-mutant lung adenocarcinoma

PURPOSE/OBJECTIVES

Radiation therapy (RT) is the principal modality in the treatment of patients with brain metastases (BM). However, given the activity of EGFR tyrosine kinase inhibitors in the central nervous system, it is uncertain whether upfront brain RT is necessary for patients with EGFR-mutant lung adenocarcinoma with BM.

METHODS AND MATERIALS

Patients with EGFR-mutant lung adenocarcinoma and newly diagnosed BM were identified.

RESULTS

222 patients were identified. Exclusion criteria included prior erlotinib use, presence of a de novo erlotinib resistance mutation, or incomplete data. Of the remaining 110 patients, 63 were treated with erlotinib, 32 with whole brain RT (WBRT), and 15 with stereotactic radiosurgery (SRS). The median overall survival (OS) for the whole cohort was 33 months. There was no significant difference in OS between the WBRT and erlotinib groups (median, 35 vs 26 months; P=.62), whereas patients treated with SRS had a longer OS than did those in the erlotinib group (median, 64 months; P=.004). The median time to intracranial progression was 17 months. There was a longer time to intracranial progression in patients who received WBRT than in those who received erlotinib upfront (median, 24 vs 16 months, P=.04). Patients in the erlotinib or SRS group were more likely to experience intracranial failure as a component of first failure, whereas WBRT patients were more likely to experience failure outside the brain (P=.004).

CONCLUSIONS

The survival of patients with EGFR-mutant adenocarcinoma with BM is notably long, whether they receive upfront erlotinib or brain RT. We observed longer intracranial control with WBRT, even though the WBRT patients had a higher burden of intracranial disease. Despite the equivalent survival between the WBRT and erlotinib group, this study underscores the role of WBRT in producing durable intracranial control in comparison with a targeted biologic agent with known central nervous system activity.

Netrin-1 expression is an independent prognostic factor for poor patient survival in brain metastases

The multifunctional molecule netrin-1 is upregulated in various malignancies and has recently been presented as a major general player in tumorigenesis leading to tumor progression and maintenance in various animal models. However, there is still a lack of clinico-epidemiological data related to netrin-1 expression. Therefore, the aim of our study was to elucidate the association of netrin-1 expression and patient survival in brain metastases since those constitute one of the most limiting factors for patient prognosis. We investigated 104 brain metastases cases for netrin-1 expression using in-situ hybridization and immunohistochemistry with regard to clinical parameters such as patient survival and MRI data. Our data show that netrin-1 is strongly upregulated in most cancer subtypes. Univariate analyses revealed netrin-1 expression as a significant factor associated with poor patient survival in the total cohort of brain metastasis patients and in sub-entities such as non-small cell lung carcinomas. Interestingly, many cancer samples showed a strong nuclear netrin-1 signal which was recently linked to a truncated netrin-1 variant that enhances tumor growth. Nuclear netrin-1 expression was associated with poor patient survival in univariate as well as in multivariate analyses. Our data indicate both total and nuclear netrin-1 expression as prognostic factors in brain metastases patients in contrast to other prognostic markers in oncology such as patient age, number of brain metastases or Ki67 proliferation index. Therefore, nuclear netrin-1 expression constitutes one of the first reported molecular biomarkers for patient survival in brain metastases. Furthermore, netrin-1 may constitute a promising target for future anti-cancer treatment approaches in brain metastases.

It Is Time to Reevaluate the Management of Patients With Brain Metastases

There are many elements to the science that drives the clinical care of patients with brain metastases. Although part of an understanding that continues to evolve, a number of key historical misconceptions remain that commonly drive physicians' and researchers' attitudes and approaches. By understanding how these relate to current practice, we can better comprehend our available science to provide both better research and care. These past misconceptions include: Misconception 1: Once a primary cancer spreads to the brain, the histology of that primary tumor does not have much impact on response to chemotherapy, sensitivity to radiation, risk of further brain relapse, development of additional metastatic lesions, or survival. All tumor primary histologies are the same once they spread to the brain. They are the same in terms of the number of tumors, radiosensitivity, chemoresponsiveness, risk of further brain relapse, and survival. Misconception 2: The number of brain metastases matters. This number matters in terms of subsequent brain relapse, survival, and cognitive dysfunction; the precise number of metastases can also be used as a limit in determining which patients might be eligible for a particular treatment option. Misconception 3: Cancer in the brain is always a diffuse problem due to the presence of micrometastases. Misconception 4: Whole-brain radiation therapy invariably causes disabling cognitive dysfunction if a patient lives long enough. Misconception 5: Most brain metastases are symptomatic. Thus, it is not worth screening patients for brain metastases, especially because the impact on survival is minimal. The conduct and findings of past clinical research have led to conceptions that affect clinical care yet appear limiting.

Brain metastasis effectively treated with erlotinib following the acquisition of resistance to gefitinib: a case report

Introduction

Non-small-cell lung cancer harboring an activated epidermal growth factor receptor mutation exhibits a good response to epidermal growth factor receptor-tyrosine kinase inhibitors; however, clinicians often experience treatment failure following the development of resistance to epidermal growth factor receptor-tyrosine kinase inhibitor.

Case presentation

We here report a case of a 56-year-old Japanese woman with non-small-cell lung carcinoma with a secondary T790M mutation associated with resistance to epidermal growth factor receptor-tyrosine kinase inhibitor that maintained sensitivity of brain metastases to epidermal growth factor receptor-tyrosine kinase inhibitor. An autopsy showed that the primary focus had a T790M mutation; however, no mutations of T790M were found in the brain metastases.

Conclusion

This case demonstrates the detection of T790M was associated with the clinical responsiveness to epidermal growth factor receptor-tyrosine kinase inhibitor.

EGFR mutated non-small cell lung cancer patients: more prone to development of bone and brain metastases?

OBJECTIVES

Both bone and brain are frequent sites of metastasis in non-small cell lung cancer (NSCLC). Conflicting data exist whether EGFR mutant (+) patients are more prone to develop brain metastases or have a better outcome with brain metastases compared to EGFR/KRAS wildtype (WT) or KRAS+ patients. For bone metastases this has not been studied.

METHODS

In this retrospective case-control study all EGFR+ (exons 19 and 21) patients diagnosed at two pathology departments were selected (2004/2008 to 2012). For every EGFR+ patient a consecutive KRAS+ and WT patient with metastatic NSCLC (mNSCLC) was identified. Patients with another malignancy within 2 years of mNSCLC diagnosis were excluded. Data regarding age, gender, performance score, histology, treatment, bone/brain metastases diagnosis, skeletal related events (SRE) and subsequent survival were collected.

RESULTS

189 patients were included: 62 EGFR+, 65 KRAS+, 62 WT. 32%, 35% and 40%, respectively, had brain metastases (p=0.645). Mean time to brain metastases was 20.8 [± 12.0], 10.8 [± 9.8], 16.4 [± 10.2] months (EGFR+-KRAS+, p = 0.020, EGFR+-WT, p = 0.321). Median post brain metastases survival was 12.1 [5.0-19.1], 7.6 [1.2-14.0], 10.7 [1.5-19.8] months (p = 0.674). 60%, 52% and 50% had metastatic bone disease (p=0.528). Mean time to development of metastatic bone disease was 13.4 [± 10.6], 23.3 [± 19.4], 16.4 [± 9.6] months (p = 0.201). Median post metastatic bone disease survival was 15.0 [10.6-20.3], 9.0 [5.2-12.9], 3.2 [0.0-6.9] months (p = 0.010). Time to 1st SRE was not significantly different.

CONCLUSIONS

Incidence of brain and bone metastases was not different between EGFR+, KRAS+ and WT patients. Post brain metastases survival, time from mNSCLC diagnosis to metastatic bone disease and 1st SRE did not differ either. Post metastatic bone disease survival was significantly longer in EGFR+ patients. Although prevention of SRE's is important for all patients, the latter finding calls for a separate study for SRE preventing agents in EGFR+ patients.

Prolonged survival of patients with non-small-cell lung cancer with leptomeningeal carcinomatosis in the modern treatment era

INTRODUCTION

Leptomeningeal carcinomatosis (LM) is a severe complication of non-small-cell lung cancer (NSCLC) historically associated with poor prognosis. New chemotherapeutic and targeted treatments could potentially affect the natural history of LM.

PATIENTS AND METHODS

Patients with a pathologic diagnosis of NSCLC with LM treated at Stanford between 2003 and 2011 were identified via institutional databases and medical records. LM was defined by cerebrospinal fluid (CSF) that was positive for malignant cells or by LM enhancement on magnetic resonance imaging with gadolinium contrast. Retrospective, landmark analyses were performed to estimate survival. Statistical analyses were performed using SAS Enterprise Guide, version 4.3.

RESULTS

LM was identified in 30 patients. All cases were adenocarcinoma; 60% of patients had a known or suspected driver mutation. The mean age was 58 years. Of the 30 patients, 67% were women; 70% were nonsmokers; 27% initially presented with LM; 84% received systemic treatment at or after development of LM; and 53% of these patients received modern systemic therapy for their LM, defined as a regimen containing pemetrexed, bevacizumab, or a tyrosine kinase inhibitor. Mean overall survival after LM diagnosis was 6 months (95% CI, 3-12). Patients who received modern systemic therapy for LM had decreased hazard of death (hazard ratio [HR], 0.24; P = .007).

CONCLUSION

In this retrospective, single-institution analysis, median survival with LM was higher compared with historical experience. Patients who received modern systemic therapy for their LM had particularly good outcomes. These data provide evidence for improving survival outcomes in the modern treatment era for this difficult-to-treat complication.

Brain metastases in non-small-cell lung cancer: better outcomes through current therapies and utilization of molecularly targeted approaches

Non-small-cell lung cancer (NSCLC) patients experience a high incidence of brain metastases, de novo and recurrent. We review the mechanisms of brain metastases and promising NSCLC molecular markers to delineate potential future therapeutic targets. Discussed are the current and previously utilized roles of surgery, radiation (both therapeutic and prophylactic), and systemic therapies in the treatment of NSCLC brain metastases. Future directions for treatment of NSCLC brain metastases will conclude our review.

EGFR mutation status and its impact on survival of Chinese non-small cell lung cancer patients with brain metastases

Brain metastasis (BM) is a leading cause of death in patients with non-small cell lung cancer (NSCLC). EGFR mutations in primary NSCLC lesions have been associated with sensitivity to EGFR tyrosine kinase inhibitor (TKI). Therefore, it has become important to understand EGFR mutation status in BM lesions of NSCLC, and its clinical implications. BM samples of 136 NSCLC patients from South China, in which 15 had paired primary lung tumors, were retrospectively analyzed for EGFR mutation by amplification mutation refractory system (ARMS). Effect of BM EGFR mutations on progression-free survival (PFS) and overall survival (OS) was evaluated by Kaplan-Meier curves and log-rank test. EGFR mutations were detected in 52.9% (72 of 136) of the BM lesions, with preference in female and never-smokers. A concordance rate of 93.3% (14 of 15) was found between the primary NSCLC and corresponding BM. Positive prediction value of testing primary NSCLCs for BM EGFR mutation is 100.0 %, and negative prediction value is 87.5%. Median PFS of BM surgery was 12 and 10 months (P = 0.594) in the wild-type and mutant group, respectively. Median OS of BM surgery was 24.5 and 15 months (P = 0.248) in the wild-type and mutant group, respectively. In conclusion, EGFR mutation status is highly concordant between the primary NSCLC and corresponding BM. The primary NSCLC could be used as surrogate samples to predict EGFR mutation status in BM lesions or vice versa. Moreover, EGFR mutations showed no significant effect on PFS or OS of NSCLCs with BM.

Challenges relating to solid tumour brain metastases in clinical trials, part 2: neurocognitive, neurological, and quality-of-life outcomes. A report from the RANO group

Neurocognitive function, neurological symptoms, functional independence, and health-related quality of life are major concerns for patients with brain metastases. The inclusion of these endpoints in trials of brain metastases and the methods by which these measures are assessed vary substantially. If functional independence or health-related quality of life are planned as key study outcomes, then the reliability and validity of these endpoints can be crucial because methodological issues might affect the interpretation and acceptance of findings. The Response Assessment in Neuro-Oncology (RANO) working group is an independent, international, and collaborative effort to improve the design of clinical trials in patients with brain tumours. In this report, the second in a two-part series, we review clinical trials of brain metastases in relation to measures of clinical benefit and provide a framework for the design and conduct of future trials.

Classification and regression tree analysis of patients with non-small-cell lung cancer treated with gefitinib after chemotherapy

BACKGROUND

Many randomized studies have shown that epidermal growth factor receptor (EGFR-) tyrosine kinase inhibitors (TKIs) are apparently advantageous over standard chemotherapy in non-small-cell lung cancer (NSCLC) patients with EGFR active mutation in front-line treatment. But which subgroup of advanced NSCLC could benefit from EGFR-TKIs in the second-or third-line setting remains elusive. To explore predictive factors of advanced NSCLC patients with the unknown status of EGFR mutation treated by gefitinib in the second-or third-line setting, we used classification and regression tree (CART) analysis to screen which patients would benefit more.

METHODS

One hundred and fifty-five patients with advanced NSCLC previously unsuccessfully treated with platinum-based chemotherapy were included in this study. Patients received gefitinib as part of the Expanded Access Program of the China Charity Federation between 2 March 2005 and 11 May 2011. Multivariate analysis of progression-free survival (PFS) was performed using CART analysis. This method uses recursive partitioning to assess the effect of specific variables on PFS, thereby ultimately generating groups of patients with similar clinical features on PFS.

RESULTS

The median PFS in patients with NSCLC who were treated with gefitinib after prior chemotherapy was 16 months (95% confidence interval [CI] 13.44-18.56). CART was performed with an initial split on adenocarcinoma differentiation, and four terminal subgroups were formed. The median PFS of the four subsets ranged from 12 to 42 months.

CONCLUSIONS

Adenocarcinoma differentiation, brain metastasis and prior thoracic radiotherapy are predictors of PFS in previously treated NSCLC patients. CART can be used to identify homogeneous patient populations in clinical practice and future clinical trials.

Phosphorylated insulin-like growth factor-1 receptor (pIGF1R) is a poor prognostic factor in brain metastases from lung adenocarcinomas

A greater understanding of brain metastases is imperative for developing novel therapeutic strategies. Our previous study showed that insulin-like growth factor (IGF) signaling pathway was activated in brain-tropic cancer cells. In this study, we investigated the clinical relevance of activated (phosphorylated) IGF-1 receptor (pIGF1R) expression in brain metastases originating from lung adenocarcinomas. All pathologically confirmed brain metastases from lung adenocarcinomas, with available archived specimens from January 1998 to December 2009 at National Taiwan University Hospital, were assessed immunohistochemically for pIGF1R expression using H-score criteria. A median H-score was used as a cutoff point to define high or low pIGF1R expression. The mutation status in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) was examined using direct sequencing. The prognostic significance of pIGF1R expression, its correlations with clinicopathological characteristics, and EGFR status were evaluated. In the 86 cases, high membranous/cytoplasmic pIGF1R expression in brain metastases correlated with a shorter median survival (10.8 vs 27.8 mo, P = 0.003). This correlation was more significant in patients with EGFR mutations [hazard ratio (HR) 2.38, 95 % confidence interval (CI) 1.19-4.77 for EGFR mutations; HR 1.99, 95 % CI 0.95-4.15 for EGFR wild type] and remained statistically significant in multivariate analysis after adjusting for the effects of other potential prognostic factors, including the graded prognostic assessment score, solitary brain metastasis, extracranial metastatic status, EGFR mutations, and treatment using EGFR tyrosine kinase inhibitors. Although we also identified nuclear pIGF1R expression, this result was prognostically non-significant. Our study results showed that high membranous/cytoplasmic pIGF1R expression in brain metastases was a poor prognostic factor, more significantly in patients with EGFR mutations than in those with wild-type EGFRs.

Predictive biochemical-markers for the development of brain metastases from lung cancer: clinical evidence and future directions

BACKGROUND

Brain metastases are a common complication of patients with lung cancer and lung cancer is one of the most common causes of brain metastases. The occurrence of brain metastases is associated with poor prognosis and high morbidity, even after intensive multimodal therapy. Therefore, identifying lung cancer patients with who are at high risk of developing brain metastases and applying effect intervention is important to reduce or delay the incidence of brain metastases. Biochemical-markers may meet an unmet need for following patients' mechanisms of brain metastases.

METHODS

Data for this review were identified by searches of Pubmed and Cochrane databases, and references from relevant articles using the search terms "lung cancer" and "brain metastasis". Meeting abstracts, unpublished reports and review articles were not considered.

RESULTS

Clinical results for pathological and circulating markers including cancer molecular subtypes, miRNA, single nucleotide polymorphisms, and other markers are presented. However, these biochemical-markers are not yet established surrogate assessments for prediction of brain metastases.

CONCLUSIONS

Biochemical-markers reported allowed physicians to identify which patients with lung cancer are at high risk for brain metastases. Prospective randomized clinical studies are needed to further assess the utility of these biochemical-markers.

Stereotactic radiosurgery in the treatment of brain metastases: the current evidence

Chemotherapy has made substantial progress in the therapy of systemic cancer, but the pharmacological efficacy is insufficient in the treatment of brain metastases. Fractionated whole brain radiotherapy (WBRT) has been a standard treatment of brain metastases, but provides limited local tumor control and often unsatisfactory clinical results. Stereotactic radiosurgery using Gamma Knife, Linac or Cyberknife has overcome several of these limitations, which has influenced recent treatment recommendations. This present review summarizes the current literature of single session radiosurgery concerning survival and quality of life, specific responses, tumor volumes and numbers, about potential treatment combinations and radioresistant metastases. Gamma Knife and Linac based radiosurgery provide consistent results with a reproducible local tumor control in both single and multiple brain metastases. Ideally minimum doses of ≥18Gy are applied. Reported local control rates were 90-94% for breast cancer metastases and 81-98% for brain metastases of lung cancer. Local tumor control rates after radiosurgery of otherwise radioresistant brain metastases were 73-90% for melanoma and 83-96% for renal cell cancer. Currently, there is a tendency to treat a larger number of brain metastases in a single radiosurgical session, since numerous studies document high local tumor control after radiosurgical treatment of >3 brain metastases. New remote brain metastases are reported in 33-42% after WBRT and in 39-52% after radiosurgery, but while WBRT is generally applied only once, radiosurgery can be used repeatedly for remote recurrences or new metastases after WBRT. Larger metastases (>8-10cc) should be removed surgically, but for smaller metastases Gamma Knife radiosurgery appears to be equally effective as surgical tumor resection (level I evidence). Radiosurgery avoids the impairments in cognition and quality of life that can be a consequence of WBRT (level I evidence). High local efficacy, preservation of cerebral functions, short hospitalization and the option to continue a systemic chemotherapy are factors in favor of a minimally invasive approach with stereotactic radiosurgery.

Brain metastasis: opportunity for drug development?

PURPOSE OF REVIEW

Brain metastases are a common clinical problem, and only limited treatment options exist. We review recent advances in medical brain metastasis research with a focus on the most common tumor types associated with secondary brain colonization: melanoma, breast cancer and lung cancer. We speculate on opportunities for drug development in patients with brain metastases, both as a treatment of established disease and as an adjuvant and prophylactic strategy.

RECENT FINDINGS

BRAF inhibitors and the immunomodulatory anticytotoxic T-lymphocyte-associated antigen 4 antibody ipilimumab have shown clinically meaningful activity in melanoma patients with brain metastases. In breast cancer, current studies on drug treatment of brain metastases are mainly focusing on human epidermal growth factor receptor 2 targeting agents such as lapatinib. Emerging data seem to implicate a potential role of targeted agents including antiangiogenic compounds, pazopanib, and epithelial growth factor receptor inhibitors for prevention of brain metastasis formation in breast cancer or nonsmall cell lung cancer.

SUMMARY

Novel drugs are beginning to enter clinical practice for selected patients with brain metastases. The promising findings from recent studies may fuel more research on brain metastases and their optimal drug treatment.

Epidemiology and prognosis of brain metastases

A substantial, but uncertain, number of patients with cancer develop brain metastases. Risk of brain metastasis is recognized to vary with type of primary cancer. Within specific types of primary cancer, prognostic factors for development of brain metastases are being recognized. Recent data suggest that molecular biomarkers that relate to cellular function can predict risk of developing brain metastases. Such information could optimize surveillance standards and/or be used to select patients for preventive interventions. Though average survival for patients with brain metastases is typically less than 6 months, it is well-recognized that subgroups of patients have significant probability of longer survival. Multiple prognostic models have been proposed, validated, and compared without clearly demonstrating superiority of one model over another. However, some factors show consistency as predictive variables across models, and performance status is almost universally significant. Application of predictive models to specific treatments has been difficult. Tumor-specific prognostic models are evolving, and combinations of biological and clinical factors may be used to optimize models for particular primary tumor types.

EGFR, KRAS, BRAF, and HER-2 molecular status in brain metastases from 77 NSCLC patients

The aim of this study was to determine the frequency of EGFR, KRAS, BRAF, and HER-2 mutations in brain metastases from non-small cell lung carcinomas (BM-NSCLC). A total of 77 samples of BM-NSCLC were included and 19 samples of BM from breast, kidney, and colorectal tumors were also studied as controls. These samples were collected from patients followed between 2008 and 2011 at Poitiers and Nice University Hospitals in France. The frequencies of EGFR, KRAS, BRAF, and HER-2 mutations in BM-NSCLC were 2.6, 38.5, 0, and 0% respectively. The incidence of KRAS mutation was significantly higher in female and younger patients (P < 0.05). No mutations of the four genes were found in BM from breast or kidney. However, among six BM from colorectal tumors, we identified KRAS mutations in three cases and BRAF mutations in two other cases. This study is the largest analysis on genetic alterations in BM-NSCLC performed to date. Our results suggest a low frequency of EGFR mutations in BM-NSCLC whereas KRAS mutations are as frequent in BM-NSCLC as in primitive NSCLC. These results raise the question of the variability of the brain metastatic potential of NSCLC cells in relation to the mutation pattern.

Targeted therapy in brain metastasis

PURPOSE OF REVIEW

To review the state of the art and new developments in the field of targeted agents for brain metastases.

RECENT FINDINGS

The huge amount of information on new molecular compounds and the advances in understanding the molecular pathways that mediate brain colonization have led to an increase of interest in preclinical and clinical investigations in the field of brain metastases. Targeted therapies can be employed either on established brain metastases or in a prevention setting. Targeting angiogenesis is an attractive approach. Up to date, large clinical trial datasets have shown that antiangiogenic agents do not increase the risk of bleeding into the brain. Bevacizumab (an anti-VEGF agent) is undergoing investigation in clinical trials on brain metastases from non-small cell lung cancer (NSCLC), breast cancer and melanoma. Sunitinib, a multitarget small molecule tyrosine kinase inhibitor (TKI), is a promising agent in brain metastases from renal cell cancer. The EGFR inhibitors gefitinib and erlotinib have a definite activity in brain metastases from NSCLC with activating EGFR mutations. Regarding HER2-positive breast cancer patients with established brain metastases, lapatinib (small molecule TKI) seems particularly active in association with capecitabine. Lapatinib alone is attractive in the prevention setting. Brain metastases from melanoma with BRAF V600E mutations respond to a specific inhibitor, such as vemurafenib. The immunomodulator ipilimumab is also active on brain metastases from melanoma.

SUMMARY

The use of targeted agents in brain metastases from solid tumors is promising. The setting of prevention will be probably expanded in the next years. Well designed clinical trials with proper endpoints are needed.

[Brain metastases of non small cell lung cancers: systemic treatments]

Chemotherapy, as all systemic treatments, is generally effective in brain metastases because the brain blood barrier (BBB) does not affect treatment's diffusion. Platinum-based chemotherapy provides response rates ranging from 23 to 50% for brain metastases. Anti-EGFR therapies are effective mostly when a somatic EGFR activating mutation is detected, or in selected population (adenocarcinoma, Asian population, never-smokers and women): response rate ranges from 38 to 69.6%. Bevacizumab is now allowed for non-small cell lung cancer (NSCLC) patients with brain metastases and non-squamous histology. The presence of untreated brain metastases may not influence its efficacy combined with paclitaxel-carboplatin. The best sequence for multimodality management of brain metastases has to be established but upfront systemic treatments in patients with asymptomatic brain metastases is a valid option.

Treating Patients With EGFR-Sensitizing Mutations: First Line or Second Line—Is There a Difference?

First-line epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) is a standard treatment for patients with activating EGFR mutations. Six randomized studies have demonstrated consistent improvement in tumor response rate and progression-free survival over platinum-based combination chemotherapy. The only reason to consider EGFR TKI as second-line therapy is that none of the six comparative studies has shown improvement in overall survival, which can be explained by the high proportion of patients from the chemotherapy arm crossing over to the EGFR TKI arm on progression. It is true that patients with EGFR mutations may benefit from second-line EGFR TKI therapy, but we cannot conclude that the benefit is either equal to or inferior to first-line EGFR TKI therapy. To date, there are no direct comparative data between first- and second-line EGFR TKI in patients with activating EGFR mutations. Tumor response rates to second-line EGFR TKI have been inconsistent, which could potentially be explained by the impact of first-line chemotherapy on the abundance of tumor cells with activating EGFR mutations. However, numerous arguments, including assurance on drug exposure, improvement in quality of life, better tolerance by patients with poor performance status, and deferral of whole-brain radiation therapy for patients with brain metastasis, support the general application of first-line EGFR TKI.

Biology of brain metastases and novel targeted therapies: time to translate the research

Brain metastases (BM) occur in 20% to 40% of patients with cancer and result in significant morbidity and poor survival. The main therapeutic options include surgery, whole brain radiotherapy, stereotactic radiosurgery and chemotherapy. Although significant progress has been made in diagnostic and therapeutic methods, the prognosis in these patients remains poor. Furthermore, the poor penetrability of chemotherapy agents through the blood brain barrier (BBB) continues to pose a challenge in the management of this disease. Preclinical evidence suggests that new targeted treatments can improve local tumor control but our clinical experience with these agents remains limited. In addition, several clinical studies with these novel agents have produced disappointing results. This review will examine the knowledge of targeted therapies in BM. The preclinical and clinical evidence of their use in BM induced by breast cancer, non-small cell lung cancer and melanoma will be presented. In addition, we will discuss the role of antiangiogenic and radiosensitising agents in the treatment of BM and the current strategies available to increase BBB permeability. A better understanding of the mechanism of action of these agents will help us to identify the best targets for testing in future clinical studies.

EGFR mutations are associated with favorable intracranial response and progression-free survival following brain irradiation in non-small cell lung cancer patients with brain metastases

BACKGROUND

The presence of epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) is associated with increased radiosensitivity in vitro. However, the results from clinical studies regarding the radiosensitivity in NSCLC with mutant EGFR are inconclusive. We retrospectively analyzed our NSCLC patients who had been regularly followed up by imaging studies after irradiation for brain metastases, and investigated the impact of EGFR mutations on radiotherapy (RT).

METHODS

Forty-three patients with brain metastases treated with RT, together with EGFR mutation status, demographics, smoking history, performance status, recursive partitioning analysis (RPA) class, tumor characteristics, and treatment modalities, were included. Radiological images were taken at 1 to 3 months after RT, and 3 to 6 months thereafter. Radiographic response was evaluated by RECIST criteria version 1.1 according to the intracranial images before and after RT. Log-rank test and Cox regression model were used to correlate EGFR mutation status and other clinical features with intracranial radiological progression-free survival (RPFS) and overall survival (OS).

RESULTS

The median follow-up duration was 15 months. Patients with mutant EGFR had higher response rates to brain RT than those with wild-type EGFR (80% vs. 46%; p = 0.037). Logistic regression analysis showed that EGFR mutation status is the only predictor for treatment response (p = 0.032). The median intracranial RPFS was 18 months (95% CI = 8.33-27.68 months). In Cox regression analysis, mutant EGFR (p = 0.025) and lower RPA class (p = 0.026) were associated with longer intracranial RPFS. EGFR mutation status (p = 0.061) and performance status (p = 0.076) had a trend to predict OS.

CONCLUSIONS

Mutant EGFR in NSCLC patients is an independent prognostic factor for better treatment response and longer intracranial RPFS following RT for brain metastases.

EGFR mutation status in brain metastases of non-small cell lung carcinoma

Brain metastases are a frequent and grave complication of non-small cell lung carcinoma (NSCLC). The prognosis is generally poor, despite standard therapy based on surgery and radiotherapy. A degree of understanding of the molecular basis of tumors has led to the development of targeted agents with promising initial findings for the treatment of NSCLC. EGFR mutations have been identified which are associated with significant sensitivity to EGFR tyrosine kinase inhibitors (TKI) and correlate with improved outcome in patients with NSCLC who are treated with these agents. The adoption of treatment tailored to the genetic make-up of individual tumors could lead to substantial therapeutic improvements, and such targeted therapy might be considered as a therapeutic option for brain metastases in the future. We review current knowledge about EGFR mutation status in the specific context of brain metastasis: its association with the response of brain metastases to TKI, its prevalence in brain metastases, and the correlation between mutation status in metastases as compared to the corresponding primary lung carcinoma.