Predictive factors associated with gefitinib response in patients with advanced non-small-cell lung cancer （NSCLC）

Purpose： A number of different clinical characteristics have been reported to singly correlate with therapeutic activity of epidermal growth factor receptor （EGFR） tyrosine kinase inhibitors （TKIs） in advanced non-small-cell lung cancer （NSCLC）. This study aimed to identify predictive factors associated with prognostic benefits of gefitinib. Patients and methods： EGFR gene typing in 33 advanced NSCLC patients received gefitinib （250 mg/day） were analyzed with mutant-enriched PCR assay. Gefitinib response was evaluated with potential predictive factors retrospectively. Results： The overall objective response rate （ORR） and median progression-flee survival （PFS） in the 33 patients treated by gefitinib were 45.5% and 3.0 （2.0-4.0） months. The ORR and median PFS in EGFR gene mutation patients were significantly higher/longer than those in EGFR gene wild-type patients （P〈0.01）. Similarly, the ORR and median PFS in non-smoker patients were significantly higher/longer than those in smoker patients （P〈0.05, P〈0.01, respectively）. However, no difference for ORR and median PFS occurred between male and female patients. Logistic multivariate analysis showed that only EGFR mutated gene was significantly associated with the ORR （P〈0.01）. Both EGFR mutated gene and non-smoker were the major factors that contributed to PFS （P〈0.05）. Conclusions： EGFR mutated gene and non-smoker status are potential predictors for gefitinib response in NSCLC patients.     

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.     

Quality of life with gefitinib in patients with EGFR-mutated non-small cell lung cancer: quality of life analysis of North East Japan Study Group 002 Trial

Background.

For non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations, first-line gefitinib produced a longer progression-free survival interval than first-line carboplatin plus paclitaxel but did not show any survival advantage in the North East Japan 002 study. This report describes the quality of life (QoL) analysis of that study.

Methods.

Chemotherapy-naïve patients with sensitive EGFR-mutated, advanced NSCLC were randomized to receive gefitinib or chemotherapy (carboplatin and paclitaxel). Patient QoL was assessed weekly using the Care Notebook, and the primary endpoint of the QoL analysis was time to deterioration from baseline on each of the physical, mental, and life well-being QoL scales. Kaplan–Meier probability curves and log-rank tests were employed to clarify differences.

Results.

QoL data from 148 patients (72 in the gefitinib arm and 76 in the carboplatin plus paclitaxel arm) were analyzed. Time to defined deterioration in physical and life well-being significantly favored gefitinib over chemotherapy (hazard ratio [HR] of time to deterioration, 0.34; 95% confidence interval [CI], 0.23–0.50; p < .0001 and HR, 0.43; 95% CI, 0.28–0.65; p < .0001, respectively).

Conclusion.

QoL was maintained much longer in patients treated with gefitinib than in patients treated with standard chemotherapy, indicating that gefitinib should be considered as the standard first-line therapy for advanced EGFR-mutated NSCLC in spite of no survival advantage.     

Experience With Afatinib in Patients With Non‐Small Cell Lung Cancer Progressing After Clinical Benefit From Gefitinib and Erlotinib

Background.

Afatinib, an irreversible ErbB family blocker, demonstrated superiority to chemotherapy as first-line treatment in patients with EGFR-mutated non-small cell lung cancer (NSCLC). Afatinib is also active in patients progressing on EGFR tyrosine kinase inhibitors (EGFR-TKIs). We report the results of a large cohort of NSCLC patients receiving afatinib within a compassionate-use program (CUP).

Patients and Methods.

Patients with advanced NSCLC progressing after one line or more of chemotherapy and one line or more of EGFR-TKI treatment with either an EGFR mutation or documented clinical benefit were enrolled. Data collection was not monitored or verified by central review. The intention of this CUP was to provide controlled preregistration access to afatinib for patients with life-threatening diseases and no other treatment option.

Results.

From May 2010 to October 2013, 573 patients (65% female; median age: 64 years [range: 28–89 years]) were enrolled, with strong participation of community oncologists. Comorbidities were allowed, including second malignancies in 11% of patients. EGFR mutation status was available in 391 patients (72%), and 83% tested mutation positive. Median time to treatment failure (TTF) of 541 patients treated with afatinib was 3.7 months (range: 0.0 to >29.0 months). Median TTF was 4.0 and 2.7 months in patients with adenocarcinomas and squamous cell carcinomas, respectively, and 4.6 months in patients with EGFR-mutated NSCLC. Adverse events were generally manageable.

Conclusion.

Afatinib was able to be given in a real-world setting to heavily pretreated patients with EGFR-mutated or EGFR-TKI-sensitive NSCLC. Acknowledging the constraints of data collection in a CUP, afatinib appears to be safe and to confer some clinical benefit in this population.     

Afatinib in Non‐Small Cell Lung Cancer Harboring Uncommon EGFR Mutations Pretreated With Reversible EGFR Inhibitors

Background.

Afatinib, an irreversible ErbB family blocker, is approved for treatment of patients with previously untreated non-small cell lung cancer (NSCLC) harboring activating epidermal growth factor receptor (EGFR) mutations. Efficacy of afatinib in EGFR tyrosine kinase inhibitor-naïve (TKI-naïve) patients with uncommon EGFR mutations (other than exon 19 deletions or exon 21 point mutations) has been reported; however, efficacy in TKI-pretreated patients with uncommon EGFR mutations is unknown.

Materials and Methods.

In the afatinib compassionate use program (CUP), patients with advanced or metastatic, histologically confirmed NSCLC progressing after at least one line of chemotherapy and one line of EGFR-TKI treatment were enrolled. Demographic data, mutation type, response rates, time to treatment failure (TTF), and safety in patients harboring uncommon EGFR mutations were reported.

Results.

In 60 patients (63% female, median age 63 years [range: 30–84 years]), a total of 66 uncommon EGFR mutations including 30 T790M mutations were reported (18.4% and 11%, respectively, of known EGFR mutations within the CUP). Most patients (67%) received afatinib as third- or fourth-line treatment. Median TTF was 3.8 months (range: 0.2 to >24.6 months; p = .244) in patients with uncommon mutations compared with 5.1 months (range: 0.1 to >21.1 months) in patients with common mutations (n = 165). Pronounced activity was observed with E709X mutations (TTF >12 months). No new safety signals were detected.

Conclusion.

Afatinib is clinically active and well tolerated in many TKI-pretreated NSCLC patients harboring uncommon EGFR mutations. Compared with results reported in TKI-naïve patients, activity was also indicated in patients with T790M and exon 20 insertion mutations.

Implications for Practice:

This analysis consists of a large database of non-small cell lung cancer patients with uncommon EGFR mutations who were previously treated with reversible EGFR tyrosine kinase inhibitors. Although indirectly assessed, the results indicate that patients with uncommon EGFR mutations can derive benefit from treatment with the irreversible ErbB family blocker afatinib, even in some cases of tumors harboring resistance-mediating exon 20 mutations. In this study, adverse events were modest and consistent with previous reports on afatinib.     

Detection of EGFR mutations in circulating free DNA by PNA-mediated PCR clamping

Background

Epidermal growth factor receptor (EGFR)-activating mutations are major determinants in predicting the tumor response to EGFR tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC). Noninvasive test for the detection of EGFR mutations is required, especially in NSCLC patients from whom tissue is not available. In this study, we assessed the feasibility of detection of EGFR mutations in free DNA circulating in plasma.

Methods

Plasma samples of 60 patients with partial response to gefitinib were analyzed to detect EGFR-activating mutations in exons 19 and 21. Forty (66.7%) of patients had tumor EGFR mutation results. EGFR mutations in plasma were detected using the peptide nucleic acid (PNA)-mediated polymerase chain reaction (PCR) clamping method. All clinical data and plasma samples were obtained from 11 centers of the Korean Molecular Lung Cancer Group (KMLCG).

Results

Of the 60 patients, 39 were female and the median age was 62.5 years. Forty-three patients never smoked, 53 had adenocarcinomas, and seven had other histologic types. EGFR-activating mutation was detected in plasma of 10 cases (exon 19 deletion in seven and exon 21 L858R point mutation in three). It could not be found in plasma after treatment for 2 months. When only patients with confirmed EGFR mutation in tumor were analyzed, 17% (6 of 35) of them showed positive plasma EGFR mutation and the mutation type was completely matched with that in tumor. There was no statistically significant difference in clinical parameters between patients with EGFR mutations in plasma and those without EGFR mutations.

Conclusions

The detection rate of EGFR mutations from plasma was not so high despite highly sensitive EGFR mutation test suggesting that more advances in detection methods and further exploration of characteristics of circulating free DNA are required.     

PTEN and PIK3CA gene copy numbers and poor outcomes in non-small cell lung cancer patients with gefitinib therapy

Background:

Preclinical studies in non-small cell lung cancer (NSCLC) suggest the interaction of PTEN and PI3K affects sensitivity to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). We investigated outcomes in relation to PTEN, PIK3CA and EGFR gene copy number, and chromosome 7 (CEN7) polysomy in NSCLC patients treated with gefitinib.

Methods:

Fluorescent in situ hybridisation analyses of PTEN, PIK3CA, EGFR and CEN7 were performed on tumour specimens from patients treated on the expanded access gefitinib trial. Progression-free survival (PFS) and overall survival (OS) were correlated with outcomes in all patients and EGFR wild-type patients.

Results:

Progression-free survival (hazard ratio=2.54, P<0.001) and OS (hazard ratio=4.04, P<0.001) were significantly shorter in patients whose tumours had all of the following molecular patterns: CEN7 <4 copies per cell, PTEN loss (<2 copies in at least 20% of cells), and PIK3CA gain (>2 copies in at least 40% of cells) both in all and EGFR wild-type only patients.

Conclusion:

The combination of low CEN7 copy number, PTEN loss, and PI3KCA gain may be useful for identifying NSCLC patients unlikely to benefit from treatment with EGFR (TKIs), specifically in wild-type EGFR cases.     

Antitumor activity of selective MEK1/2 inhibitor AZD6244 in combination with PI3K/mTOR inhibitor BEZ235 in gefitinib-resistant NSCLC xenograft models

Purpose

Although the EGF receptor tyrosine kinase inhibitors (EGFR-TKI) gefitinib have shown dramatic effects against EGFR mutant lung cancer, patients become resistant by various mechanisms, including gatekeeper EGFR-T790M mutation, MET amplification, and KRAS mutation, thereafter relapsing. AZD6244 is a potent, selective, and orally available MEK1/2 inhibitor. In this study, we evaluated the therapeutic efficacy of AZD6244 alone or with BEZ235, an orally available potent inhibitor of phosphatidylinositol 3–kinase (PI3K) and mammalian target of rapamycin (mTOR), in gefitinib-resistant non-small cell lung carcinoma (NSCLC) models.

Experimental design

NCI-H1975 with EGFR-T790M mutation, NCI-H1993 with MET amplification and NCI-H460 with KRAS/PIK3CA mutation human NSCLC cells were subcutaneous injected into the athymic nude mice respectively. Mice were randomly assigned to treatment with AZD6244, BEZ235, AZD6244 plus BEZ235, or control for 3 weeks, then all mice were sacrificed and tumor tissues were subjected to western blot analyses and immunohistochemical staining.

Results

AZD6244 could inhibit the tumor growth of NCI-H1993, but slightly inhibit the tumor growth of NCI-1975 and NCI-H460. Combining AZD6244 with BEZ235 markedly enhanced their antitumor effects and without any marked adverse events. Western blot analysis and immunohistochemical staining revealed that AZD6244 alone reduced ERK1/2 phosphorylation, angiogenesis, and tumor cell proliferation. Moreover, MEK1/2 inhibition resulted in decreased AKT phosphorylation in NCI-H1993 tumor model. BEZ235 also inhibited AKT phosphorylation as well as their downstream molecules in all three tumor models. The antiangiogenic effects were substantially enhanced when the agents were combined, which may due to the reduced expression of matrix metallopeptidase-9 in tumor tissues (MMP-9).

Conclusions

In this study, we evaluated therapy directed against MEK and PI3K/mTOR in distinct gefitinib-resistant NSCLC xenograft models. Combining AZD6244 with BEZ235 enhanced their antitumor and antiangiogenic effects. We concluded that the combination of a selective MEK inhibitor and a PI3K/mTOR inhibitor was effective in suppressing the growth of gefitinib-resistant tumors caused by EGFR T790M mutation, MET amplification, and KRAS/PIK3CA mutation. This new therapeutic strategy may be a practical approach in the treatment of these patients.     

Serum levels of surfactant protein D predict the anti-tumor activity of gefitinib in patients with advanced non-small cell lung cancer

Purpose

Gefitinib is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that has dramatic effects in selective patients with non-small cell lung cancer (NSCLC). A simple non-invasive method for predicting the efficacy of gefitinib is preferable in clinical settings. In this study, we evaluated prospectively whether surfactant protein-A (SP-A) and -D (SP-D) may be new conventional predictors of the efficacy of gefitinib treatment.

Methods

We measured serum SP-A and SP-D levels on days 0 and 29 in 40 patients with advanced NSCLC treated with 250?mg gefitinib daily. Eligibility criteria included performance status ??3, age ??80?years, and stage IIIB?CIV disease. In addition, EGFR mutations were analyzed in 24 patients.

Results

Multivariate analysis showed that favorable progression-free survival (PFS) after gefitinib treatment was associated with adenocarcinoma and high serum SP-D levels before treatment. EGFR mutation analysis of 24 patients showed that 16 patients had exon 19 deletion and/or exon 21 point mutations. EGFR mutations were significantly correlated with response to gefitinib and serum SP-D levels before treatment was significantly high in patients with the EGFR mutations. Serum SP-A levels were not associated with PFS.

Conclusions

The present study showed that measurement of serum SP-D levels before treatment in patients with NSCLC may be a new surrogate marker for predicting the response to gefitinib.     

DNA Methylation status of Wnt antagonist SFRP5 can predict the response to the EGFR-tyrosine kinase inhibitor therapy in non-small cell lung cancer

Background

It is well known that genetic alternation of epidermal growth factor receptor (EGFR) plays critical roles in tumorgenesis of lung cancer and can predict outcome of non-small-cell lung cancer treatment, especially the EGFR tyrosine-kinase inhibitors (EGFR-TKIs) therapy. However, it is unclear whether epigenetic changes such as DNA methylation involve in the response to the EGFR-TKI therapy.

Methods

Tumor samples from 155 patients with stages IIIB to IV NSCLC who received EGFR-TKI therapy were analyzed for DNA methylation status of Wnt antagonist genes, including SFRP1, SFRP2, SFRP5, DKK3, WIF1, and APC, using methylation specific PCR (MSP) method. EGFR mutations detections were performed in the same tissues samples using Denaturing High Performance Liquid Chromatography (DHPLC).

Results

We found that Wnt antagonists tend to methylate simultaneously. Methylation of sFRP1 and sFRP5 are reversely correlated with EGFR mutation (P = 0.005, P = 0.011). However, no correlations of methylations of other Wnt antagonist genes with EGFR mutation were found. The patients with methylated SFRP5 have a significant shorter progression free survival than those with unmethylated SFRP5 in response to EGFR-TKI treatment (P = 0.002), which is independent of EGFR genotype.

Conclusions

Patients with unmethylated SFRP5 are more likely to benefit from EGFR-TKI therapy.     

Revisiting Clinical Trials Using EGFR Inhibitor-Based Regimens in Patients with Advanced Non-Small Cell Lung Cancer: A Retrospective Analysis of an MD Anderson Cancer Center Phase I Population

Purpose

Single-agent EGFR inhibitor therapy is effective mainly in patients with lung cancer and EGFR mutations. Treating patients who develop resistance, or who are insensitive from the outset, often because of resistant mutations, other aberrations or the lack of an EGFR mutation, probably requires rational combinations. We therefore investigated the outcome of EGFR inhibitor-based combination regimens in patients with heavily-pretreated non-small cell lung cancer (NSCLC) referred to a Phase I Clinic.

Methods

We reviewed the electronic records of patients with NSCLC treated with an EGFR inhibitor-based combination regimen: erlotinib and cetuximab; erlotinib, cetuximab and bevacizumab; erlotinib and dasatinib; erlotinib and bortezomib; or cetuximab and sirolimus.

Results

EGFR mutations were detected in 16% of patients (21/131). EGFR inhibitor-based combination regimens were administered to 15 patients with EGFR-mutant NSCLC and 24 with EGFR wild-type disease. Stable disease (SD) ≥6 months/partial remission (PR) was attained in 20% of EGFR-mutant patients (3/15; two with sensitive mutations and secondary resistance to prior erlotinib, and one with a resistant mutation), as well as 26% of evaluable patients (5/19) with wild-type disease. One of three evaluable patients with squamous cell histology achieved SD for 26.5 months (EGFR wild-type, TP53-mutant, regimen=erlotinib, cetuximab and bevacizumab).

Conclusions

Eight of 34 evaluable patients (24%) with advanced, refractory NSCLC evaluable for response achieved SD ≥6 months/PR (PR=3; SD ≥6 months=5) on EGFR inhibitor-based combination regimens (erlotinib, cetuximab; erlotinib, cetuximab and bevacizumab; and, erlotinib, bortezomib), including patients with secondary resistance to single-agent EGFR inhibitors, resistant mutations, wild-type disease, and, squamous histology.     

Coexistence of EGFR with KRAS,or BRAF,or PIK3CA somatic mutations in lung cancer: a comprehensive mutation profiling from 5125 Chinese cohorts

Background:

Determining the somatic mutations of epidermal growth factor receptor (EGFR)-pathway networks is the key to effective treatment for non-small cell lung cancer (NSCLC) with tyrosine kinase inhibitors (TKIs).The somatic mutation frequencies and their association with gender, smoking history and histology was analysed and reported in this study.

Methods:

Five thousand one hundred and twenty-five NSCLC patients'' pathology samples were collected, and EGFR, KRAS, BRAF and PIK3CA mutations were detected by multiplex testing. The mutation status of EGFR, KRAS, BRAF and PIK3CA and their association with gender, age, smoking history and histological type were evaluated by appropriate statistical analysis.

Results:

EGFR, KRAS, BRAF and PIK3CA mutation rates revealed 36.2%, 8.4%, 0.5% and 3.3%, respectively, across the 5125 pathology samples. For the first time, evidence of KRAS mutations were detected in two female, non-smoking patients, age 5 and 14, with NSCLC. Furthermore, we identified 153 double and coexisting mutations and 7 triple mutations. Interestingly, the second drug-resistant mutations, T790M or E545K, were found in 44 samples from patients who had never received TKI treatments.

Conclusions:

EGFR exons 19, 20 and 21, and BRAF mutations tend to happen in females and non-smokers, whereas KRAS mutations were more inclined to males and smokers. Activating and resistant mutations to EGFR-TKI drugs can coexist and ‘second drug-resistant mutations'', T790M or E545K, may be primary mutations in some patients. These results will help oncologists to decide candidates for mutation testing and EGFR-TKI treatment.     

Clinical characteristics of non-small cell lung cancer patients who experienced acquired resistance during gefitinib treatment

Background

The NSCLC patients who experienced good clinical responses to an EGFR-TKI will inevitably develop acquired resistance. A great deal of research is being carried out to discover the molecular mechanisms underlying this resistance. In comparison, few studies have been conducted to find out about the clinical characteristics of acquired resistance in the patients who had responded to an EGFR-TKI. Herein we investigated clinical characteristics of NSCLC patients who experienced acquired resistance during gefitinib therapy.

Patients and methods

We reviewed NSCLC patients who showed a clinical benefit from initial gefitinib therapy. All clinical data were obtained from 11 centers of Korean Molecular Lung Cancer Group (KMLCG). The clinical manifestations of acquired resistance, time to progression (TTP), and post-progression survival (PPS) after gefitinib failure were analyzed retrospectively.

Results

A total of 417 patients were recruited. Median TTP was 10.2 months (95% CI, 9.5–10.9). TTP showed a significant longer duration in female, non-smoker, and patients with adenocarcinoma. At the time of acquired resistance, 63.3% of the patients showed symptomatic deterioration. Sites of disease progression were as follows: primary lung lesion in 58.4%, previous metastasis in 38.3%, and new metastasis in 54.2%. Patients with EGFR wild type showed a tendency of higher frequency in symptomatic deterioration and newly development of CNS metastasis compared with patients with EGFR mutation. There was a significant difference in newly development of lung metastasis between patients with exon 19 deletion and those with L858R mutation (41.4% vs. 6.3%, p = 0.02). PPS was 8.9 months (95% CI, 7.4–10.4). Smoking history, PS, new CNS lesion and subsequent chemotherapy were independent factors for PPS.

Conclusion

This study suggests that clinical manifestations of acquired resistance may be different according to EGFR mutation status and EGFR mutation genotype. In addition, subsequent chemotherapy confers clinical benefit in terms of PPS in NSCLC patients who experienced acquired resistance after gefitinib therapy.     

Low EGFR/MET ratio is associated with resistance to EGFR inhibitors in non-small cell lung cancer

Purpose

Although activating mutations in the epidermal growth factor receptor (EGFR) gene are predictive markers for response to EGFR inhibitors, 30–40% of EGFR-mutant non-small cell lung cancer (NSCLC) patients are de novo non-responders. Hence, we sought to explore additional biomarkers of response.

Methods

We conducted a prospective pilot study to characterize the expression and/or activation of key receptor tyrosine kinases (RTKs) in stage IIIB-IV NSCLC tumors. A total of 37 patients were enrolled and 34 underwent EGFR inhibitor treatment.

Results

As expected, patients bearing activating EGFR mutations showed increased progression free survival (PFS) compared to patients with wild-type EGFR status (9.3 vs 1.4 months, p = 0.0629). Analysis of baseline tumor RTK profiles revealed that, regardless of EGFR mutation status, higher levels of EGFR relative to MET correlated with longer PFS. At multiple EGFR/MET ratio cut-offs, including 1, 2 and 3, median PFS according to below vs. above cut-offs were 0.4 vs. 6.1 (p = 0.0001), 0.5 vs. 9.3 (p = 0.0006) and 1.0 vs. 11.2 months (p = 0.0008), respectively.

Conclusion

The EGFR/MET ratio measured in tumors at baseline may help identify NSCLC patients most likely to benefit from prolonged PFS when treated with EGFR inhibitors.     

Outcomes after combined modality therapy for EGFR-mutant and wild-type locally advanced NSCLC

Background.

Epidermal growth factor receptor (EGFR) mutations identify a unique biological subtype of non-small cell lung cancer (NSCLC). Treatment outcomes for EGFR-mutant locally advanced NSCLC patients have not been well described.

Methods.

We retrospectively examined outcomes after combined modality therapy including thoracic radiation therapy (RT) in 123 patients with locally advanced NSCLC and known EGFR mutation status. Outcomes were compared using Kaplan–Meier analysis, the log-rank test, and multivariate Cox regression models.

Results.

All 123 patients underwent thoracic RT; 25% had tumors with EGFR mutations and 94% had stage III disease. Overall, 81% received chemotherapy concurrent with RT and 55% underwent surgical resection. With a median follow-up of 27.5 months, the overall survival (OS) rate was significantly higher in patients with EGFR-mutant tumors than in those with wild-type EGFR tumors (2-year estimate: 92.6% versus 69.0%; p = .04). The 2-year relapse-free survival and distant recurrence rates did not differ significantly by genotype. The 2-year locoregional recurrence rate (LRR) was significantly lower in EGFR-mutant than in wild-type EGFR patients (17.8% versus 41.7%; p = .005). EGFR-mutant genotype was associated with a lower risk for LRR on multivariate analysis, but not OS, after adjusting for surgery and other potential confounders.

Conclusion.

We observed that EGFR-mutant patients with locally advanced NSCLC treated with RT had lower rates of LRR than wild-type EGFR patients, raising the hypothesis that EGFR mutations may confer sensitivity to RT and/or chemotherapy. The association between mutation status and OS after combined modality therapy was less robust. Our data may serve as a useful baseline estimate of outcomes by EGFR genotype for future prospective studies.     

Gefitinib Versus Adjuvant Chemotherapy in Patients With Stage II-IIIA Non–Small-Cell Lung Cancer Harboring Positive EGFR Mutations: A Single-Center Retrospective Study

Background

The superior efficacy of first-line treatment with gefitinib over that of standard chemotherapy was demonstrated in patients with advanced non–small-cell lung cancer (NSCLC) harboring sensitive mutation of epidermal growth factor receptor (EGFR). However, scarce evidence showing the superiority of gefitinib to chemotherapy exists regarding the postoperative adjuvant therapy of EGFR mutation–positive patients with stage II-IIIA NSCLC. To address this important gap, we undertook a retrospective study to assess the efficacy of adjuvant gefitinib versus adjuvant chemotherapy (AC) in patients with completely resected EGFR-mutant stage II-IIIA NSCLC.

A Phase I/II Study Combining Erlotinib and Dasatinib for Non‐Small Cell Lung Cancer

Background.

EGFR and Src are frequently activated in non-small cell lung cancer (NSCLC). In preclinical models, combining EGFR and Src inhibition has additive synergistic effects. We conducted a phase I/II trial of the combination of Src inhibitor dasatinib with EGFR inhibitor erlotinib to determine the maximum tolerated dose (MTD), pharmacokinetic drug interactions, biomarkers, and efficacy in NSCLC.

Methods.

The phase I 3+3 dose-escalation study enrolled patients with solid tumors to determine the MTD. The phase II trial enrolled patients with advanced NSCLC who had undergone no previous treatments to determine progression-free survival (PFS) and response. Pharmacokinetic and tissue biomarker analyses were performed.

Results.

MTD was 150 mg of erlotinib and 70 mg of dasatinib daily based on 12 patients treated in the phase I portion. No responses were observed in phase I. The 35 NSCLC patients treated in phase II had an overall disease control rate of 59% at 6 weeks. Five patients (15%) had partial responses; all had activating EGFR mutations. Median PFS was 3.3 months. Epithelial-mesenchymal transition markers did not correlate with outcomes.

Conclusion.

The combination of erlotinib and dasatinib is safe and feasible in NSCLC. The results of this study do not support use of this combination in molecularly unselected NSCLC.     

Gefitinib selectively inhibits tumor cell migration in EGFR-amplified human glioblastoma

Background

Tissue invasion is a hallmark of most human cancers and remains a major source of treatment failure in patients with glioblastoma (GBM). Although EGFR amplification has been previously associated with more invasive tumor behavior, existing experimental models have not supported quantitative evaluation of interpatient differences in tumor cell migration or testing of patient-specific responses to therapies targeting invasion. To explore these questions, we optimized an ex vivo organotypic slice culture system allowing for labeling and tracking of tumor cells in human GBM slice cultures.

Methods

With use of time-lapse confocal microscopy of retrovirally labeled tumor cells in slices, baseline differences in migration speed and efficiency were determined and correlated with EGFR amplification in a cohort of patients with GBM. Slices were treated with gefitinib to evaluate anti-invasive effects associated with targeting EGFR.

Results

Migration analysis identified significant patient-to-patient variation at baseline. EGFR amplification was correlated with increased migration speed and efficiency compared with nonamplified tumors. Critically, gefitinib resulted in a selective and significant reduction of tumor cell migration in EGFR-amplified tumors.

Conclusions

These data provide the first identification of patient-to-patient variation in tumor cell migration in living human tumor tissue. We found that EGFR-amplified GBM are inherently more efficient in their migration and can be effectively targeted by gefitinib treatment. These data suggest that stratified clinical trails are needed to evaluate gefitinib as an anti-invasive adjuvant for patients with EGFR-amplified GBM. In addition, these results provide proof of principle that primary slice cultures may be useful for patient-specific screening of agents designed to inhibit tumor invasion.     

First-line gefitinib in Caucasian EGFR mutation-positive NSCLC patients: a phase-IV,open-label,single-arm study

Background:

Phase-IV, open-label, single-arm study ({"type":"clinical-trial","attrs":{"text":"NCT01203917","term_id":"NCT01203917"}}NCT01203917) to assess efficacy and safety/tolerability of first-line gefitinib in Caucasian patients with stage IIIA/B/IV, epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC).

Methods:

Treatment: gefitinib 250 mg day⁻¹ until progression. Primary endpoint: objective response rate (ORR). Secondary endpoints: disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and safety/tolerability. Pre-planned exploratory objective: EGFR mutation analysis in matched tumour and plasma samples.

Results:

Of 1060 screened patients with NSCLC (859 known mutation status; 118 positive, mutation frequency 14%), 106 with EGFR sensitising mutations were enrolled (female 70.8% adenocarcinoma 97.2% never-smoker 64.2%). At data cutoff: ORR 69.8% (95% confidence interval (CI) 60.5–77.7), DCR 90.6% (95% CI 83.5–94.8), median PFS 9.7 months (95% CI 8.5–11.0), median OS 19.2 months (95% CI 17.0–NC; 27% maturity). Most common adverse events (AEs; any grade): rash (44.9%), diarrhoea (30.8%); CTC (Common Toxicity Criteria) grade 3/4 AEs: 15% SAEs: 19%. Baseline plasma 1 samples were available in 803 patients (784 known mutation status; 82 positive; mutation frequency 10%). Plasma 1 EGFR mutation test sensitivity: 65.7% (95% CI 55.8–74.7).

Conclusion:

First-line gefitinib was effective and well tolerated in Caucasian patients with EGFR mutation-positive NSCLC. Plasma samples could be considered for mutation analysis if tumour tissue is unavailable.     

Predictive value of K-ras and PIK3CA in non-small cell lung cancer patients treated with EGFR-TKIs: a systemic review and meta-analysis

Objective

A meta-analysis was performed to augment the insufficient data on the impact of mutative EGFR downstream phosphatidylinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways on the clinical efficiency of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment of non-small cell lung cancer (NSCLC) patients.

Methods

Network databases were explored in April, 2015. Papers that investigated the clinical outcomes of NSCLC patients treated with EGFR-TKIs according to the status of K-ras and/or PIK3CA gene mutation were included. A quantitative meta-analysis was conducted using standard statistical methods. Odds ratios (ORs) for objective response rate (ORR) and hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS) were calculated.

Results

Mutation in K-ras significantly predicted poor ORR [OR =0.22; 95% confidence interval (CI), 0.13-0.35], shorter PFS (HR =1.56; 95% CI, 1.27-1.92), and shorter OS (HR =1.59; 95% CI, 1.33-1.91) in NSCLC patients treated with EGFR-TKIs. Mutant PIK3CA significantly predicted shorter OS (HR =1.83; 95% CI, 1.05-3.20), showed poor ORR (OR =0.70; 95% CI, 0.22-2.18), and shorter PFS (HR =1.79; 95% CI, 0.91-3.53) in NSCLC patients treated with EGFR-TKIs.

Conclusion

K-ras mutation adversely affected the clinical response and survival of NSCLC patients treated with EGFR-TKIs. PIK3CA mutation showed similar trends. In addition to EGFR, adding K-ras and PIK3CA as routine gene biomarkers in clinical genetic analysis is valuable to optimize the effectiveness of EGFR-TKI regimens and identify optimal patients who will benefit from EGFR-TKI treatment.KEYWORDS : Non-small cell lung cancer (NSCLC), tyrosine kinase inhibitor (TKI), targeted therapy, K-ras, PIK3CA, meta-analysis