Prospective phase II study of gefitinib in non-small cell lung cancer with epidermal growth factor receptor gene mutations

QT-Interval Prolongation, Torsades de Pointes, and Heart Failure With EGFR Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer: Systematic Review

A systematic literature review was conducted to determine the incidence and mortality of QT-interval prolongation (QTp), torsades de pointes (TdP), and heart failure (HF) in patients with non-small cell lung cancer (NSCLC) who received epidermal growth factor receptor (EGFR) TKIs. Of 296 identified publications, 95 met eligibility criteria and were abstracted for QTp/TdP and HF outcomes (QTp/TdP: 83 publications, including 5 case study publications; HF: 79 publications, including 6 case study publications [involving 8 patients]). QTp incidence ranged from 0% to 27.8% in observational studies and from 0% to 11% in clinical trials, with no deaths due to QTp. There were no TdP events or deaths due to TdP. The incidence of HF ranged from 0% to 8%, and HF mortality rates ranged from 0% to 4%. Patients receiving treatment with EGFR TKIs should be monitored for signs of QTp, TdP, and HF per prescribing information. Standardized definitions and methods to improve monitoring of QTp, TdP, and HF-related events are needed in patients with NSCLC.

Differential efficacy of tyrosine kinase inhibitors according to the types of EGFR mutations and agents in non-small cell lung cancer: a real-world study

BACKGROUND

Both first and second-generation EGFR-TKIs are recommended in advanced NSCLC with common EGFR mutations. However, there are few data on the difference in efficacy of EGFR-TKIs based on the type of EGFR mutation and agents.

METHODS

This retrospective real-world study evaluated the outcomes and clinicopathologic characteristics, including the type of EGFR mutations, of 237 advanced NSCLC patients treated with first- or second-generation (afatinib) EGFR-TKIs as first-line therapy.

RESULTS

The median progression-free survival (PFS) and overall survival (OS) of all patients were 11 months (M) and 25M, respectively. In the univariate analysis, patients with exon 19 deletion (del) (n=130) had significantly longer median OS compared to those with other mutations (L858R: 84, others: 23) (30 vs. 22 M, p=0.047), without a difference in PFS (p=0.138). Patients treated with afatinib (n=60) showed significantly longer median OS compared to those treated with first-generation TKIs (gefitinib: 159, erlotinib: 18) (30 vs. 23 M, p=0.037), without a difference in PFS (p=0.179). In patients with exon 19 del, there was no significant difference in median PFS (p=0.868) or OS (p=0.361) between patients treated with afatinib and those treated with first-generation TKIs, while significantly better PFS (p=0.042) and trend in OS (p=0.069) were observed in patients receiving afatinib in other mutations. Exon 19 del was independently associated with favorable OS (p=0.028), while age >70 years (p=0.017), ECOG performance status ≥2 (p=0.001), primary metastatic disease (p=0.007), and synchronous brain metastasis (p=0.026) were independent prognostic factors of poor OS.

CONCLUSIONS

The EGFR exon 19 del was associated with favorable OS in advanced NSCLC patients receiving first-line EGFR-TKIs. Moreover, in patients with exon 19 del, first-generation TKIs seem to be a reasonable treatment option if osimertinib is unavailable.

Empirical methods for the validation of time-to-event mathematical models taking into account uncertainty and variability: application to EGFR + lung adenocarcinoma

BACKGROUND

Over the past several decades, metrics have been defined to assess the quality of various types of models and to compare their performance depending on their capacity to explain the variance found in real-life data. However, available validation methods are mostly designed for statistical regressions rather than for mechanistic models. To our knowledge, in the latter case, there are no consensus standards, for instance for the validation of predictions against real-world data given the variability and uncertainty of the data. In this work, we focus on the prediction of time-to-event curves using as an application example a mechanistic model of non-small cell lung cancer. We designed four empirical methods to assess both model performance and reliability of predictions: two methods based on bootstrapped versions of parametric statistical tests: log-rank and combined weighted log-ranks (MaxCombo); and two methods based on bootstrapped prediction intervals, referred to here as raw coverage and the juncture metric. We also introduced the notion of observation time uncertainty to take into consideration the real life delay between the moment when an event happens, and the moment when it is observed and reported.

RESULTS

We highlight the advantages and disadvantages of these methods according to their application context. We have shown that the context of use of the model has an impact on the model validation process. Thanks to the use of several validation metrics we have highlighted the limit of the model to predict the evolution of the disease in the whole population of mutations at the same time, and that it was more efficient with specific predictions in the target mutation populations. The choice and use of a single metric could have led to an erroneous validation of the model and its context of use.

CONCLUSIONS

With this work, we stress the importance of making judicious choices for a metric, and how using a combination of metrics could be more relevant, with the objective of validating a given model and its predictions within a specific context of use. We also show how the reliability of the results depends both on the metric and on the statistical comparisons, and that the conditions of application and the type of available information need to be taken into account to choose the best validation strategy.

Knowledge-based mechanistic modeling accurately predicts disease progression with gefitinib in EGFR-mutant lung adenocarcinoma

Lung adenocarcinoma (LUAD) is associated with a low survival rate at advanced stages. Although the development of targeted therapies has improved outcomes in LUAD patients with identified and specific genetic alterations, such as activating mutations on the epidermal growth factor receptor gene (EGFR), the emergence of tumor resistance eventually occurs in all patients and this is driving the development of new therapies. In this paper, we present the In Silico EGFR-mutant LUAD (ISELA) model that links LUAD patients' individual characteristics, including tumor genetic heterogeneity, to tumor size evolution and tumor progression over time under first generation EGFR tyrosine kinase inhibitor gefitinib. This translational mechanistic model gathers extensive knowledge on LUAD and was calibrated on multiple scales, including in vitro, human tumor xenograft mouse and human, reproducing more than 90% of the experimental data identified. Moreover, with 98.5% coverage and 99.4% negative logrank tests, the model accurately reproduced the time to progression from the Lux-Lung 7 clinical trial, which was unused in calibration, thus supporting the model high predictive value. This knowledge-based mechanistic model could be a valuable tool in the development of new therapies targeting EGFR-mutant LUAD as a foundation for the generation of synthetic control arms.

Icotinib, an EGFR tyrosine kinase inhibitor, as adjuvant therapy for patients with stage IIA-IIIA EGFR-mutant non-small-cell lung adenocarcinoma: a multicenter, open-label, single-arm, phase II study (ICAPE)

The survival benefit of icotinib (an oral epidermal growth factor receptor [EGFR] tyrosine kinase inhibitor) in patients with advanced lung cancer has been confirmed in several studies. This study (ICAPE) evaluated the efficacy of icotinib as adjuvant therapy for patients with stage IIA-IIIA EGFR-mutant non-small-cell lung adenocarcinoma. Patients with stage IIA-IIIA EGFR-mutant non-small-cell lung adenocarcinoma were enrolled in the multicenter, open-label, single-arm, phase II study. Eligible patients received oral icotinib 125 mg thrice daily for 1.5 years after complete surgical resection. The primary endpoint was disease-free survival (DFS). Between March 2014 and January 2018, 79 patients were enrolled. The median follow-up time was 39.7 months with a median DFS and overall survival (OS) of 41.4 months (95% CI: 33.6-51.8) and 67.0 months (95% CI: 21.2-not reached [NR]), respectively. The 1-year, 3-year, and 5-year OS rates were 100%, 83.3%, and 61.7%, respectively. No significant difference was found in the median DFS between patients with Bcl-2 interacting mediator of cell death (BIM) mutant-type and wild-type (NR vs. 41.7 months; p = 0.75). No significant difference was found in the median DFS according to EGFR mutation types. Icotinib as adjuvant therapy demonstrated a favorable survival benefit in patients with stage IIA-IIIA EGFR-mutant non-small-cell lung adenocarcinoma, indicating that icotinib might be a promising treatment option for this patient population. The optimal adjuvant duration of icotinib is still not clear and needs more incoming data to answer.

Identification of TCR rearrangements specific for genetic alterations in EGFR-mutated non-small cell lung cancer: results from the ADJUVANT-CTONG1104 trial

Tumor response T cells, which have specific T cell receptor (TCR) rearrangements in tumor-infiltrating lymphocytes, determine their ability to interact with the mutation-derived neoantigens presented by antigen-presenting cells. Little is known about the genetic alterations related to specific TCR clones in non-small cell lung cancer (NSCLC) patients who have an epidermal growth factor receptor (EGFR) mutation. In this study, tumor tissues were collected from 101 patients with stage II/III resectable NSCLC with an EGFR mutation (57 patients were treated with gefitinib and 44 were treated with chemotherapy) in the ADJUVANT-CTONG1104 trial for high-throughput TCRβ V region and exome sequencing. Ten clonal TCRs were associated with EGFR exon 19 deletion (del), EGFR exon 21 mutation (L858R), RB1 alteration, TP53 exon 4/5 missense mutation, TP53 nonsense mutation, or copy number gains in NKX2-1 and CDK4. Among the TCRs, there was frequent use of Vβ20-1Jβ2-3 specifically for EGFR exon 19 del or Vβ9Jβ2-1 specifically for EGFR exon 21 mutation (L858R), and these were significantly associated with favorable overall survival (OS) for NSCLC patients harboring EGFR exon 19 del or exon 21 L858R, particularly in the adjuvant gefitinib setting. Moreover, in comparison with the chemotherapy-preferable (CP) group, higher frequencies of Vβ20-1Jβ2-3 and Vβ9Jβ2-1 were found in the highly TKI-preferable (HTP) or TKI-preferable (TP) groups. Altogether, we identified ten TCR rearrangements specific for genetic alterations in NSCLC. Importantly, high abundance Vβ20-1Jβ2-3 or Vβ9Jβ2-1 may be an immune biomarker for guiding adjuvant gefitinib decisions for NSCLC patients harboring EGFR exon 19 del or EGFR exon 21 L858R.

Third-generation EGFR and ALK inhibitors: mechanisms of resistance and management

The discoveries of EGFR mutations and ALK rearrangements as actionable oncogenic drivers in non-small-cell lung cancer (NSCLC) has propelled a biomarker-directed treatment paradigm for patients with advanced-stage disease. Numerous EGFR and ALK tyrosine kinase inhibitors (TKIs) with demonstrated efficacy in patients with EGFR-mutant and ALK-rearranged NSCLCs have been developed, culminating in the availability of the highly effective third-generation TKIs osimertinib and lorlatinib, respectively. Despite their marked efficacy, resistance to these agents remains an unsolved fundamental challenge. Both 'on-target' mechanisms (largely mediated by acquired resistance mutations in the kinase domains of EGFR or ALK) and 'off-target' mechanisms of resistance (mediated by non-target kinase alterations such as bypass signalling activation or phenotypic transformation) have been identified in patients with disease progression on osimertinib or lorlatinib. A growing understanding of the biology and spectrum of these mechanisms of resistance has already begun to inform the development of more effective therapeutic strategies. In this Review, we discuss the development of third-generation EGFR and ALK inhibitors, predominant mechanisms of resistance, and approaches to tackling resistance in the clinic, ranging from novel fourth-generation TKIs to combination regimens and other investigational therapies.

Genomic characteristics in Chinese non-small cell lung cancer patients and its value in prediction of postoperative prognosis

Background

The genomic profile of non-small cell lung cancer (NSCLC) in Asians is distinct from that of Caucasians, but comprehensive genetic profiling reports have been limited for Asian patients. We aimed to elucidate genomic characteristics of Chinese NSCLC patients and develop potential model including genomic characteristics to predict postoperative prognosis.

Methods

Resected tumor samples from 511 patients with stage I–IV lung cancer were subjected to targeted sequencing using a panel of 295 cancer-related genes. Based on the molecular profiles and clinical features, we established nomogram models with predictors consisting of integrated clinical and genomic characteristics to provide post-operative risk stratification.

Results

Compared to the TCGA population (mainly Caucasians), there was a significantly higher frequency of EGFR (53.7% vs. 14.4%) and NOTCH3 (8.4% vs. 1.3%) mutations and less mutated KRAS (11.0% vs. 32.6%), KEAP1 (4.4% vs. 17.4%) and LRP1B (16.3% vs. 29.6%) in Chinese lung adenocarcinomas (LUAD). Distinct patterns of mutually exclusive and co-occurring mutations were identified between LUAD and lung squamous cell carcinoma (LUSC), indicating the unique histology-specific tumorigenesis mechanism of each subtype. We observed alterations in pathways correlated with clinical characteristics. Additionally, we constructed nomogram model with predictors consisting of clinical and genomic characteristics, which were more accurate than models with clinical characteristics or TNM staging only both in stage I–IIIA patients and T1-2N0M0 sub-cohort.

Conclusions

This study revealed Chinese NSCLC patients have unique genomic profile. Furthermore, the nomogram model combining clinical features with genomic characteristics could improve risk stratification in early-stage NSCLC.

Prognostic value of EGFR 19-del and 21-L858R mutations in patients with non-small cell lung cancer

Previous studies have demonstrated a significant difference in clinical characteristics between patients with non-small cell lung cancer (NSCLC) harboring exon 19 deletion (19-del) and an exon point mutation (21-L858R) in EGFR. The present retrospective study aimed to investigate the differential prognosis in patients with NSCLC harboring exon 19-del and 21-L858R mutations. The clinical and follow-up data of 137 patients treated at the Zhongnan Hospital of Wuhan University (Wuhan, Hubei, China) between August 2012 and August 2016, who were diagnosed with stage IIIB-IV NSCLC harboring either exon 19-del or 21-L858R mutations, were analyzed. The patients were divided into the first-line tyrosine kinase inhibitor (TKI), first-line chemotherapy and second-line TKI treatment groups. The median progression-free survival (PFS) time of patients harboring the exon 19-del mutation was significantly improved compared with that in patients harboring the 21-L858R mutation (11.3 vs. 8.8 months, respectively; P=0.017) following first-line TKI treatments. However, no significant difference in the median PFS time was observed between the exon 19-del and 21-L858R groups following the first-line chemotherapy or second-line TKI treatment. In patients with the exon 19-del, first-line TKI treatment achieved an increased objective response rate (ORR; 51.9 vs. 18.5%; P=0.004) and disease control rate (96.2 vs. 77.8%; P=0.030), and a longer PFS time (11.3 vs. 8.0 months; P=0.034) compared with that in the patients following first-line chemotherapy. First- and second-line TKI treatment achieved a similar PFS time (11.3 vs. 11.0 months, respectively; P=0.140). However, in patients with the 21-L858R mutation, the first-line TKI therapy and first-line chemotherapy groups exhibited a similar PFS time (8.8 vs. 3.5 months, respectively; P=0.063), while the second-line TKI treatment group exhibited a significantly longer PFS time compared with the first-line TKI treatment group (13.6 vs. 8.8 months, respectively; P=0.030). There was a differential sensitivity to treatment between patients harboring the exon 19-del and 21-L858R mutations. Therefore, chemotherapy may increase the sensitivity to TKIs in patients harboring the 21-L858R mutation.

EGFR Exon 19 Deletion is Associated With Favorable Overall Survival After First-line Gefitinib Therapy in Advanced Non-Small Cell Lung Cancer Patients

OBJECTIVES

Exon 19 deletion and L858R mutation in exon 21 of the epidermal growth factor receptor (EGFR) are both common mutations that predict a good response to EGFR tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC). However, the existence of clinically significant difference in sensitivity to EGFR tyrosine kinase inhibitors among different EGFR mutation subtypes is still a matter of debate.

MATERIALS AND METHODS

The outcome of 60 EGFR mutation-positive advanced NSCLC patients who received first-line gefitinib therapy (250 mg/d) was retrospectively analyzed according to EGFR mutation subtypes.

RESULTS

The median progression-free survival (PFS) and overall survival (OS) after the initiation of gefitinib therapy for all patients was 11 and 26 months, respectively. Univariate analysis showed that patients with exon 19 deletion (n=28) had significantly longer median PFS (20 vs. 8 mo, P=0.004) and OS (36 vs. 22 mo, P=0.001) compared with those with L858R mutation (n=25) and uncommon or dual mutations (n=7). Multivariate analysis revealed that exon 19 deletion (P=0.007) was an independent prognostic factor of favorable PFS, with an independent association with poor PFS of male sex (P=0.049). Exon 19 deletion was also independently associated with favorable OS (P<0.0001), whereas male sex (P=0.004) and primary metastatic disease (P=0.032) were independent prognostic factors of poor OS.

CONCLUSIONS

The EGFR exon 19 deletion was associated with favorable PFS and OS in patients receiving first-line gefitinib treatment. The EGFR mutation subtype should be considered when making treatment decision or designing clinical trials for chemotherapy-naive, EGFR mutation-positive advanced NSCLC patients.

Pneumonitis in advanced non-small-cell lung cancer patients treated with EGFR tyrosine kinase inhibitor: Meta-analysis of 153 cohorts with 15,713 patients: Meta-analysis of incidence and risk factors of EGFR-TKI pneumonitis in NSCLC

PURPOSE

Pneumonitis is a significant toxicity of EGFR tyrosine kinase inhibitors (EGFR-TKI) in non-small-cell lung cancer (NSCLC) patients. We studied the incidence of pneumonitis in clinical trials of EGFR-TKI published in 2003-2017, and performed subgroups analyses to identity predisposing factors.

METHODS

Ovid-MEDLINE and EMBASE search up to 4/17/17 using the keywords, "erlotinib", "gefitinib", "afatinib", "osimertinib", and "lung cancer", resulted in a total of 153 eligible trial cohorts with 15,713 advanced NSCLC patients treated with EGFR-TKI. The pooled incidence of all-grade, high-grade, and grade 5 pneumonitis was obtained. Subgroup analyses were performed with meta-regression using study-level covariates.

RESULTS

Among the patients without prior exposure to EGFR-TKI, the overall incidence was 1.12% (95% CI:0.79-1.58%) for all-grade, 0.61% (95% CI:0.40-0.93%) for high-grade, and 0.20% (95% CI:0.11-0.38%) for grade 5 pneumonitis. The incidence was significantly higher in Japanese studies compared to studies of non-Japan origin, for all-grade (4.77% vs. 0.55%, p < 0.001), high grade (2.49% vs. 0.37%, p < 0.001), and grade 5 pneumonitis (1.00% vs. 0.18%, p < 0.001). Multivariate analyses demonstrated higher odds of pneumonitis in Japanese studies for all-grade (odds ratio [OR]: 5.04; 95% CI:3.14-8.11, p < 0.001), high-grade (OR: 4.45; 95% CI:2.50-7.93, p < 0.001), and grade 5 pneumonitis (OR: 4.55; 95% CI:2.20-9.44, p < 0.001) compared to others, after adjusting for types of EGFR-TKI and lines of therapy. In patients with EGFR retreatment analyzed separately, the pooled incidence was 1.13% (95% CI:0.40-3.15%) for all-grade, 0.49% (95% CI:0.21-1.11%) for high-grade, and 0.16% (95% CI:0.04-0.65%) for grade 5 pneumonitis.

CONCLUSIONS

The overall incidence of EGFR-TKI pneumonitis was 1.12% in patients without prior exposure to EGFR-TKI, and 1.13% in EGFR-TKI retreatment group. The cohorts from Japan had significantly higher incidence of pneumonitis, providing insights for further mechanistic studies.

EGFR G796D mutation mediates resistance to osimertinib

Osimertinib is an effective third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) approved in multiple countries and regions for patients with EGFR T790M mutation-positive non-small cell lung cancer (NSCLC). Despite impressive initial tumor responses, development of drug resistance ultimately limits the benefit of this compound. Mechanisms of resistance to osimertinib are just beginning to emerge, such as EGFR C797S and L718Q mutations, BRAF V600E and PIK3CA E545K mutations, as well as ERBB2 and MET amplification. However, a comprehensive view is still missing. In this study, we presented the first case of Chinese NSCLC patient who developed resistance to osimertinib, and discovered de novo EGFR G796D mutation as a potential mechanism. Our findings provided insights into mechanisms of resistance to osimertinib and highlighted tumor heterogeneity and clonal evolution during the development of drug resistance.

Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology

CONTEXT

- In 2013, an evidence-based guideline was published by the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology to set standards for the molecular analysis of lung cancers to guide treatment decisions with targeted inhibitors. New evidence has prompted an evaluation of additional laboratory technologies, targetable genes, patient populations, and tumor types for testing.

OBJECTIVE

- To systematically review and update the 2013 guideline to affirm its validity; to assess the evidence of new genetic discoveries, technologies, and therapies; and to issue an evidence-based update.

DESIGN

- The College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology convened an expert panel to develop an evidence-based guideline to help define the key questions and literature search terms, review abstracts and full articles, and draft recommendations.

RESULTS

- Eighteen new recommendations were drafted. The panel also updated 3 recommendations from the 2013 guideline.

CONCLUSIONS

- The 2013 guideline was largely reaffirmed with updated recommendations to allow testing of cytology samples, require improved assay sensitivity, and recommend against the use of immunohistochemistry for EGFR testing. Key new recommendations include ROS1 testing for all adenocarcinoma patients; the inclusion of additional genes ( ERBB2, MET, BRAF, KRAS, and RET) for laboratories that perform next-generation sequencing panels; immunohistochemistry as an alternative to fluorescence in situ hybridization for ALK and/or ROS1 testing; use of 5% sensitivity assays for EGFR T790M mutations in patients with secondary resistance to EGFR inhibitors; and the use of cell-free DNA to "rule in" targetable mutations when tissue is limited or hard to obtain.

Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology

CONTEXT

In 2013, an evidence-based guideline was published by the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology to set standards for the molecular analysis of lung cancers to guide treatment decisions with targeted inhibitors. New evidence has prompted an evaluation of additional laboratory technologies, targetable genes, patient populations, and tumor types for testing.

OBJECTIVE

To systematically review and update the 2013 guideline to affirm its validity; to assess the evidence of new genetic discoveries, technologies, and therapies; and to issue an evidence-based update.

DESIGN

The College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology convened an expert panel to develop an evidence-based guideline to help define the key questions and literature search terms, review abstracts and full articles, and draft recommendations.

RESULTS

Eighteen new recommendations were drafted. The panel also updated 3 recommendations from the 2013 guideline.

CONCLUSIONS

The 2013 guideline was largely reaffirmed with updated recommendations to allow testing of cytology samples, require improved assay sensitivity, and recommend against the use of immunohistochemistry for EGFR testing. Key new recommendations include ROS1 testing for all adenocarcinoma patients; the inclusion of additional genes (ERBB2, MET, BRAF, KRAS, and RET) for laboratories that perform next-generation sequencing panels; immunohistochemistry as an alternative to fluorescence in situ hybridization for ALK and/or ROS1 testing; use of 5% sensitivity assays for EGFR T790M mutations in patients with secondary resistance to EGFR inhibitors; and the use of cell-free DNA to "rule in" targetable mutations when tissue is limited or hard to obtain.

Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology

CONTEXT

In 2013, an evidence-based guideline was published by the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology to set standards for the molecular analysis of lung cancers to guide treatment decisions with targeted inhibitors. New evidence has prompted an evaluation of additional laboratory technologies, targetable genes, patient populations, and tumor types for testing.

OBJECTIVE

To systematically review and update the 2013 guideline to affirm its validity; to assess the evidence of new genetic discoveries, technologies, and therapies; and to issue an evidence-based update.

DESIGN

The College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology convened an expert panel to develop an evidence-based guideline to help define the key questions and literature search terms, review abstracts and full articles, and draft recommendations.

RESULTS

Eighteen new recommendations were drafted. The panel also updated 3 recommendations from the 2013 guideline.

CONCLUSIONS

The 2013 guideline was largely reaffirmed with updated recommendations to allow testing of cytology samples, require improved assay sensitivity, and recommend against the use of immunohistochemistry for EGFR testing. Key new recommendations include ROS1 testing for all adenocarcinoma patients; the inclusion of additional genes (ERBB2, MET, BRAF, KRAS, and RET) for laboratories that perform next-generation sequencing panels; immunohistochemistry as an alternative to fluorescence in situ hybridization for ALK and/or ROS1 testing; use of 5% sensitivity assays for EGFR T790M mutations in patients with secondary resistance to EGFR inhibitors; and the use of cell-free DNA to "rule in" targetable mutations when tissue is limited or hard to obtain.

Intercalated Treatment Following Rebiopsy Is Associated with a Shorter Progression-Free Survival of Osimertinib Treatment

Purpose

Epidermal growth factor receptor (EGFR) T790M mutation serves as an important predictor of osimertinib efficacy. However, little is known about how it works among patients with various timings of T790M emergence and treatment.

Materials and Methods

Advanced EGFR-mutant lung adenocarcinoma patients with positive T790M mutation in tumor were retrospectively enrolled and observed to determine the outcomes of osimertinib treatment. We evaluated the association between patients’ characteristics and the efficacy of osimertinib treatment, particularly with respect to the timing of T790M emergence and osimertinib prescription.

Results

A total of 91 patients were enrolled, including 14 (15.4%) with primary and 77 (84.6%) with acquired T790M mutation. The objective response rate and disease controlratewere 60.9% and 85.1%, respectively. The median progression-free survival (PFS) and overall survival were 11.5 months (95% confidence interval [CI], 9.0 to 14.0) and 30.4 months (95% CI, 11.3 to 49.5), respectively. There was no significant difference in response rate and PFS between primary and acquired T790M populations. In the acquired T790M subgroup, patientswho received osimertinib after T790M had been confirmed by rebiopsy had a longer PFS than those with intercalated treatments between rebiopsy and osimertinib prescription (14.0 months [95% CI, 9.0 to 18.9] vs. 7.2 months [95% CI, 3.7 to 10.8]; adjusted hazard ratio, 0.48 [95% CI, 0.24 to 0.98; p=0.043]). Rebiopsy timing did not influence the outcome.

Conclusion

Osimertinib prescription with intercalated treatment following rebiopsy but not the timing of T790M emergence influenced the treatment outcome. We suggest that it is better to start osimertinib treatment once T790M mutation has been confirmed by biopsy.

Does the efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor differ according to the type of EGFR mutation in non-small cell lung cancer?

An exon 19 deletion and a L858R mutation in exon 21 of the epidermal growth factor receptor (EGFR) are the two most common mutations that predict favorable efficacy of EGFR tyrosine kinase inhibitors (TKIs) in patients with non-small cell lung cancer (NSCLC). Many retrospective and prospective studies, as well as meta-analyses including patients with NSCLC with various lines of EGFR TKI treatment, have demonstrated longer progression-free survival and sometimes more favorable overall survival in patients with an exon 19 deletion than those with the L858R or other mutations. In contrast, some clinical studies, including phase III trials, have demonstrated no difference in the efficacy of EGFR TKIs according to the EGFR mutation type. Therefore, the existence of clinically significant differences in sensitivity to EGFR-TKIs among different EGFR mutation subtypes remains controversial. In this review, we summarize the evidence suggesting different outcomes according to the type of EGFR mutation in patients with advanced NSCLC who were treated with EGFR-TKIs, along with their clinical significance. We also discuss possible mechanisms that can explain the different sensitivities to EGFR TKIs between cases with an exon 19 deletion and those with the L858R mutation.

Second-Line Treatment of NSCLC-The Pan-ErbB Inhibitor Afatinib in Times of Shifting Paradigms

In contrast to the established role of epidermal growth factor receptor (EGFR) inhibitors for the first-line treatment of patients with non-small cell lung cancer (NSCLC) harboring activating EGFR mutations, the role of EGFR blockade and of EGFR molecular testing in the second-line treatment remains less clear. The irreversible pan-ErbB family inhibitor afatinib (Gi(l)otrif^®) was recently FDA- and EMA-approved for the second-line treatment of NSCLC with squamous cell histology irrespective of the EGFR mutational status (LUX-Lung 8). Contrariwise, results from the TAILOR and DELTA trials among retrospective biomarker analyses show the predictive value of the EGFR mutational status for efficacy of reversible EGFR inhibitors also as a second-line therapy. This mini review critically summarizes the current role of EGFR-targeting strategies in the second-line treatment of NSCLC with special respect to afatinib in light of emerging T790M-specific EGFR and immune check point inhibitors. The review also emphasizes the urgent need for reliable biomarkers to guide therapeutic decision-making and outlines prospective changes to the second-line landscape with some of the current second-line treatment concepts likely to be moved to the first-line.

EGFR Mutation Subtypes Influence Survival Outcomes following First-Line Gefitinib Therapy in Advanced Asian NSCLC Patients

INTRODUCTION

Activating mutations in the EGFR gene have been shown to confer sensitivity to EGFR tyrosine kinase inhibitors in patients with advanced NSCLC. However, wide interpatient variability in treatment outcomes in response to EGFR tyrosine kinase inhibitors in these patients remains unaccounted for. This study aimed to evaluate the influence of EGFR mutation types and subtypes on survival outcomes in advanced Asian patients with NSCLC receiving first-line gefitinib therapy.

METHODS

Patients with stage IIIB or IV NSCLC who were harboring EGFR mutations, receiving first-line gefitinib treatment, and of Asian descent (N = 383) were evaluated. Overall survival (OS) and progression-free survival (PFS) were estimated by Kaplan-Meier analysis. Log-rank tests and Cox proportional hazards models were implemented to evaluate the differences in PFS and OS.

RESULTS

Significant differences in PFS were observed between patients carrying EGFR mutations in exons 18, 19, 20, and 21, with patients carrying EGFR exon 19 mutations having the longest median PFS (overall p = 8.88 × 10^-15). Comparison of PFS among the five different exon 19 mutation subtypes and among the two exon 19 deletion start codons did not reveal any significant differences. No significant difference was observed in OS among patients carrying EGFR mutations on different exons (overall p = 0.054); however, OS was found to be significantly different among the various subtypes of exon 19 mutations, with the 15-nucleotide deletion "non-ELREA" group having the shortest OS of 11.3 months (overall p = 0.025).

CONCLUSIONS

EGFR mutation types and subtypes significantly influence survival outcomes in patients with advanced NSCLC who are receiving first-line gefitinib treatment.

Comparison of clinical outcomes of patients with non-small-cell lung cancer harbouring epidermal growth factor receptor exon 19 or exon 21 mutations after tyrosine kinase inhibitors treatment: a meta-analysis

PURPOSE

Exon 19 deletion and exon 21 L858R mutation were the most common epidermal growth factor receptor (EGFR) mutations. We examined the clinical impact of these two mutations in patients with non-small-cell lung cancer (NSCLC) after EGFR tyrosine kinase inhibitor (TKI) treatment.

METHODS

The outcomes of interest were progression-free survival (PFS), overall survival (OS) and objective response rates (ORR), network meta-analysis and direct meta-analysis were conducted to calculate the efficacy of EGFR-TKIs between these two mutations. We also investigated the association between EGFR mutation types and clinical characteristics.

RESULTS

A total of 4835 patients from 26 trials were assessed. EGFR-TKIs, compared with chemotherapy, significantly prolonged PFS and OS in both exon 19 deletion and exon 21 L858R mutation based on 8 trials. Network meta-analysis revealed that treatment with EGFR-TKIs had greater benefit in exon 19 deletion than in exon 21 L858R mutation. Furthermore, direct meta-analysis from 12 studies showed the similar result; patients with exon 19 deletion had a significantly longer PFS compared with exon 21 L858R mutation (HR, 0.69; 95 % CI, 0.57–0.82; P < 0.001). There were also greater benefit on OS (HR, 0.61; 95 % CI, 0.43–0.86; P = 0.005) and higher ORR (OR, 2.14; 95 % CI, 1.63–2.81; P < 0.001). Additionally, we found that a significant association between the type of mutation and age (P < 0.001) or smoking status (P = 0.022), but no other significant differences were detected in sex, histologic subtype and performance status between these two mutations.

CONCLUSIONS

Patients with NSCLC and EGFR exon 19 deletion had a longer PFS, OS and higher response rates after EGFR-TKI therapy compared with exon 21 L858R mutation.

Epidermal growth factor receptor-tyrosine kinase inhibitor therapy is especially beneficial to patients with exon 19 deletion compared with exon 21 L858R mutation in non-small-cell lung cancer: Systematic review and meta analysis

BACKGROUND

The correlation between epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and EGFR sensitive mutation subtypes in advanced or metastatic non-small cell lung cancer (NSCLC) remains uncertain. We performed this meta-analysis to determine different clinical outcomes between patients with exon 19 deletion accepting EGFR-TKI therapy compared with those with exon 21 L858R mutation.

METHODS

PubMed and Web of Science were analyzed for eligible trials. Raw data were extracted to give pooled estimates of the effect of EGFR-TKI therapy on objective response rate (ORR), one-year progression-free survival (PFS), and two-year overall survival (OS).

RESULTS

We identified 13 eligible trials involving 912 patients. Prospective meta-analysis demonstrated that the ORR of the 19 deletion group was significantly higher than the 21 L858R mutation group (odds ratio [OR] 1.98, 95% confidence interval [CI] 1.18-3.33; P = 0.01), but no statistical significance between the one-year PFS rate of the 19 deletion and 21 L858R groups (OR 1.44, 95% CI 0.96-2.18; P = 0.08) was found. However, retrospective meta-analysis demonstrated that a significantly higher one-year PFS rate was associated with the 19 deletion group (OR 1.73, 95% CI 1.17-2.56; P = 0.006). The two-year survival rate of the 19 deletion group was significantly higher than the 21 L858R group (OR 5.27, 95 % CI 1.76-15.71; P = 0.003).

CONCLUSIONS

In advanced NSCLC patients, an exon 19 deleton may provide superior ORR, PFS, and OS after EGFR-TKI treatment compared with an exon 21 L858R mutation.

Phase I/II study of gefitinib (Iressa(®)) and vorinostat (IVORI) in previously treated patients with advanced non-small cell lung cancer

PURPOSE

Vorinostat has been shown to overcome resistance to gefitinib. We performed a phase I/II study combining gefitinib with vorinostat in previously treated non-small cell lung cancer (NSCLC).

METHODS

A 3 + 3 dose-escalation design was used to determine maximum tolerated dose (MTD) and recommended phase II dose (RP2D). Three dose levels were tested: 250 mg/day gefitinib on days 1-28 and 200, 300 or 400 mg/day vorinostat on days 1-7, and 15-21 out of every 28 days. The primary endpoint was median progression-free survival (PFS).

RESULTS

Fifty-two patients were enrolled and treated (43 in phase II). The median age was 59 years, 28 patients were male, 44 had adenocarcinoma, 29 had never smoked, and 36 had undergone one prior treatment. Twenty-two patients exhibited sensitive EGFR mutations. Planned dose escalation was completed without reaching the MTD. The RP2D was 250 mg gefitinib and 400 mg vorinostat. In 43 assessable patients in phase II, the median PFS was 3.2 months; the overall survival (OS) was 19.0 months. There were 16 partial responses and six cases of stable disease. In EGFR-mutant NSCLC, response rate was 77 %, median PFS was 9.1 months, and median OS was 24.1 months. The most common adverse events were anorexia and diarrhea.

CONCLUSIONS

Treatment with 250 mg gefitinib daily with biweekly 400 mg/day vorinostat was feasible and well tolerated. In an unselected patient population, this combination dose did not improve PFS. However, this combination showed a potential for improving efficacy of gefitinib in EGFR-mutant NSCLC (NCT01027676).

Pooled safety analysis of EGFR-TKI treatment for EGFR mutation-positive non-small cell lung cancer

OBJECTIVES

Three epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) - afatinib, erlotinib, and gefitinib - are available for the treatment of patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). Given the long-term exposure of such patients to EGFR-TKIs, the toxicological properties of these agents in these individuals may differ from those observed in unselected patients. We compared the frequencies of severe adverse events (AEs) among EGFR mutation-positive NSCLC patients treated with these three EGFR-TKIs.

MATERIALS AND METHODS

We performed a pooled analysis of severe AEs according to the type of EGFR-TKI administered with the use of data extracted from prospective clinical trials that evaluated the clinical efficacy of gefitinib, erlotinib, or afatinib in NSCLC patients with EGFR mutations.

RESULTS

Twenty-one trials published between 2006 and 2014 and including 1468 patients were eligible for analysis. Patients in 13 trials (n=457) received gefitinib, those in 5 trials (n=513) received erlotinib, and those in 3 trials (n=498) received afatinib. Rash and diarrhea of grade ≥3 were significantly more frequent with afatinib therapy than with erlotinib or gefitinib therapy. The frequency of interstitial lung disease (ILD) of grade ≥3 was low (0.6-2.2%) with all three EGFR-TKIs and did not differ significantly among them. Gefitinib was associated with a significantly higher frequency of hepatotoxicity of grade ≥3 compared with erlotinib or afatinib. The overall frequency of AEs leading to treatment withdrawal was 6.1% (83 of 1354 evaluable patients), with such AEs occurring significantly more often with afatinib or gefitinib than with erlotinib. The most common withdrawal AEs were skin toxicity, ILD, and hepatotoxicity.

CONCLUSION

Such information on AEs should facilitate selection of the most appropriate EGFR-TKI for EGFR mutation-positive NSCLC patients with regard to mitigation of the risk for certain types of toxicity.

Different efficacy of EGFR tyrosine kinase inhibitors and prognosis in patients with subtypes of EGFR-mutated advanced non-small cell lung cancer: a meta-analysis

BACKGROUND

Nearly 85 % of lung-cancer-specific epidermal growth factor receptor (EGFR) sensitive mutations comprise a substitution at position 858 (21L858R) and deletion mutants in exon 19 (19del). The aim of this study was to assess the role of EGFR mutation subtypes in predicting the efficacy of EGFR tyrosine kinase inhibitors (EGFR TKIs) and the prognosis of patients with advanced non-small cell lung cancer (NSCLC).

METHOD

We systematically searched for eligible articles investigating the association between EGFR mutation subtypes and the efficacy of EGFR TKIs and the prognosis of patients with NSCLC. The summary risk ratio (RR) and mean difference (MD) were calculated using meta-analysis. In addition, we used variance analysis for the progression-free survival data (PFS) and used the rank sum test for the overall survival data.

RESULTS

We identified 22 eligible trials involving 1,082 patients. The objective response rate of the 19del mutation group was significantly higher than the 21L858R mutation group (RR 1.23; 95 % CI 1.12-1.36; P < 0.0001). The PFS (MD 3.55; 95 % CI 0.90-6.20; P = 0.009; MD 2.57; 95 % CI 0.51-4.62; P = 0.01) and overall survival (OS) (MD 10.52; 95 % CI 5.10-15.93; P = 0.0001) of the 19del mutation group were significantly longer than the 21L858R mutation group; the same results were observed in the variance analysis and rank sum test.

CONCLUSION

The 19del mutation may be a more efficient clinical marker for predicting the response of patients with NSCLC to EGFR TKIs. Furthermore, patients with the 19del mutation have both a longer PFS and OS. The 19del mutation is also the prognostic factor for patients with NSCLC.

EGFR mutations as a prognostic and predictive marker in non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) has entered the age of individual treatment, and increasing point mutations of specific oncogenes and rearrangement of some chromosomes are biomarkers used to predict the therapeutic effect of targeted therapy. At present, there is a consensus among clinicians that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have shown favorable efficacy in NSCLC patients with EGFR mutation, and some relevant research has suggested that the presence of EGFR mutations is a favorable prognostic marker. However, the association of EGFR mutation status with the responsiveness to conventional chemotherapy agents and survival in NSCLC patients is still unclear. This review provides an overview of and assesses the role of EGFR as a prognostic marker for postoperative patients and as a predictive marker for response to cytotoxic chemotherapy. In addition, we review the comparison of response to chemotherapy between EGFR mutations in exon 19 and in exon 21 and the predictive role of p.T790M mutation.

Prognostic value of epidermal growth factor receptor mutations in resected non-small cell lung cancer: a systematic review with meta-analysis

BACKGROUND

The prognostic value of epidermal growth factor receptor (EGFR) mutations in resected non-small cell lung cancer (NSCLC) remains controversial. We performed a systematic review with meta-analysis to assess its role.

METHODS

Studies were identified via an electronic search on PubMed, Embase and Cochrane Library databases. Pooled hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS) were calculated for meta-analysis.

RESULTS

There were 16 evaluated studies (n  =  3337) in the meta-analysis. The combined HR evaluating EGFR mutations on disease free survival was 0.96 (95% CI [0.79-1.16] P  =  0.65). The combined HR evaluating EGFR mutations on overall survival was 0.86 (95% CI [0.72-1.04] P  = 0.12). The subgroup analysis based on univariate and multivariate analyses in DFS and OS showed no statistically significant difference. There was also no statistically significant difference in DFS and OS of stage I NSCLC patients.

CONCLUSION

The systematic review with meta-analysis showed that EGFR mutations were not a prognostic factor in patients with surgically resected non-small cell lung cancer. Well designed prospective study is needed to confirm the result.

Pooled analysis of clinical outcome for EGFR TKI-treated patients with EGFR mutation-positive NSCLC

Patients with non-small-cell lung cancer (NSCLC) appear to gain particular benefit from treatment with epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitors (TKI) if their disease tests positive for EGFR activating mutations. Recently, several large, controlled, phase III studies have been published in NSCLC patients with EGFR mutation-positive tumours. Given the increased patient dataset now available, a comprehensive literature search for EGFR TKIs or chemotherapy in EGFR mutation-positive NSCLC was undertaken to update the results of a previously published pooled analysis. Pooling eligible progression-free survival (PFS) data from 27 erlotinib studies (n = 731), 54 gefitinib studies (n = 1802) and 20 chemotherapy studies (n = 984) provided median PFS values for each treatment. The pooled median PFS was: 12.4 months (95% accuracy intervals [AI] 11.6-13.4) for erlotinib-treated patients; 9.4 months (95% AI 9.0-9.8) for gefitinib-treated patients; and 5.6 months (95% AI 5.3-6.0) for chemotherapy. Both erlotinib and gefitinib resulted in significantly longer PFS than chemotherapy (permutation testing; P = 0.000 and P = 0.000, respectively). Data on more recent TKIs (afatinib, dacomitinib and icotinib) were insufficient at this time-point to carry out a pooled PFS analysis on these compounds. The results of this updated pooled analysis suggest a substantial clear PFS benefit of treating patients with EGFR mutation-positive NSCLC with erlotinib or gefitinib compared with chemotherapy.

Detection of mutations by fill-in ligation reaction with enzyme-linked immunosorbent assay for rapid medical diagnosis

Several approaches for parallel genotyping have been developed with increasingly available information on DNA variation. However, these methods require either complex laboratory procedures or expensive instrumentation. None of these procedures is readily performed in local clinical laboratories. In this study, we developed a flexible genotyping method involving fill-in ligation reaction with enzyme-linked immunosorbent assay successfully applied to detect important single-nucleotide polymorphisms (SNPs) for EGFR c.2573T > G (L858R), EGFR c.2582T > A (L861Q), and EGFR c.2155G > T (G719C). This assay exhibited excellent specificity, with a sensitivity as low as 0.5%. Eight out of 62 clinical samples were identified as heterozygotes for the SNP site of L858R, whereas only two samples were identified as heterozygotes by direct sequencing. The developed method enabled accurate identification of SNP in a simple and cost-effective manner adapted to routine analysis.

Molecular Targeted Drugs and Biomarkers in NSCLC, the Evolving Role of Individualized Therapy

Lung cancer first line treatment has been directed from the non-specific cytotoxic doublet chemotherapy to the molecular targeted. The major limitation of the targeted therapies still remains the small number of patients positive to gene mutations. Furthermore, the differentiation between second line and maintenance therapy has not been fully clarified and differs in the clinical practice between cancer centers. The authors present a segregation between maintenance treatment and second line and present a possible definition for the term “maintenance” treatment. In addition, cancer cell evolution induces mutations and therefore either targeted therapies or non-specific chemotherapy drugs in many patients become ineffective. In the present work pathways such as epidermal growth factor, anaplastic lymphoma kinase, met proto-oncogene and PI3K are extensively presented and correlated with current chemotherapy treatment. Future, perspectives for targeted treatment are presented based on the current publications and ongoing clinical trials.

[Personalized targeted therapy for lung cancer]

由于每一肺癌患者在临床特征、预后、治疗反应和耐受性方面的进展都是独特的，所以肺癌被认为是异质性疾病。个体化用药是指运用标志物来预测哪些患者更易获益于某种治疗。对于肺癌而言，日趋完善的表皮生长因子受体(epidermal growth factor receptor, EGFR)和新发现的棘皮动物微管相关蛋白样4-间变淋巴瘤激酶(echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase, EML4-ALK)是重要的治疗靶标。本综述包括EGFR和EML4-ALK活化的机制、预测性生物标记物、耐药的机理和已有的靶向性酪氨酸激酶抑制剂。本文将通过总结基于生物标记物筛选患者而进行的前瞻性临床试验来探讨EGFR和ALK靶向治疗的疗效。此外，由于革命性的测序和系统生物学技术会为癌症的分子特征提供一个全面的理解，有助于为更适宜靶向治疗的患者提供更精确的区分从而提供更有前景的个体化治疗，本综述也将包括这些技术。同时，非亚裔人群中EGFR和ALK相对较低的突变发生率和突变患者反应的缺乏限制了靶向于EGFR或ALK的治疗的应用。测序和系统生物学策略则可能为这些患者提供新的解决方案。

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture published articles from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. EVIDENCE was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture articles published published from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. Evidence was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Epidermal growth factor receptor tyrosine kinase inhibitors as initial therapy for non-small cell lung cancer: focus on epidermal growth factor receptor mutation testing and mutation-positive patients

Activation of the epidermal growth factor receptor (EGFR) pathway has been implicated in tumorigenesis in non-small cell lung cancer (NSCLC), the most common type of lung cancer. As a result, EGFR has become a key focus for the development of personalized therapy, with several molecular biomarkers having been investigated as potential predictors of response with EGFR tyrosine kinase inhibitors (TKIs) in NSCLC (e.g., EGFR expression, EGFR gene copy gain, and EGFR mutations). Of these, activating mutations in EGFR have thus far given the most consistent results based on the available evidence from preclinical studies and clinical trials. In an attempt to identify patients who are most likely to benefit from treatment with EGFR TKIs, EGFR mutation testing is being increasingly utilized in clinical practice. Currently in the United States, no EGFR TKI or accompanying mutational test is approved for the identification and first-line treatment of patients with advanced NSCLC. However, the first-generation EGFR TKIs, erlotinib and gefitinib, as well as investigational ErbB family TKIs and EGFR mutation testing methods are being evaluated in this setting. This review will discuss EGFR mutation testing as a biomarker of response to EGFR TKIs and the evolution of EGFR mutational analysis in NSCLC. Completed and ongoing clinical trials evaluating currently available or investigational EGFR TKIs as first-line therapy in molecularly and clinically selected patients with NSCLC, with a focus on trials in patients whose tumors have EGFR mutations, will also be reviewed.

Molecularly targeted approaches herald a new era of non-small-cell lung cancer treatment

The discovery of activating mutations in the epidermal growth-factor receptor (EGFR) gene in 2004 opened a new era of personalized treatment for non-small-cell lung cancer (NSCLC). EGFR mutations are associated with a high sensitivity to EGFR tyrosine kinase inhibitors, such as gefitinib and erlotinib. Treatment with these agents in EGFR-mutant NSCLC patients results in dramatically high response rates and prolonged progression-free survival compared with conventional standard chemotherapy. Subsequently, echinoderm microtubule-associated protein-like 4 (EML4)–anaplastic lymphoma kinase (ALK), a novel driver oncogene, has been found in 2007. Crizotinib, the first clinically available ALK tyrosine kinase inhibitor, appeared more effective compared with standard chemotherapy in NSCLC patients harboring EML4-ALK. The identification of EGFR mutations and ALK rearrangement in NSCLC has further accelerated the shift to personalized treatment based on the appropriate patient selection according to detailed molecular genetic characterization. This review summarizes these genetic biomarker-based approaches to NSCLC, which allow the instigation of individualized therapy to provide the desired clinical outcome.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture articles published from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. Evidence was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Mutations of the EGFR and K-ras genes in resected stage I lung adenocarcinoma and their clinical significance

PURPOSE

This study retrospectively assessed the mutations of the epidermal growth factor receptor (EGFR) and K-ras genes and their clinical significance in patients with resected stage I adenocarcinomas.

METHODS

A total of 354 patients with resected lung adenocarcinomas were included, and 256 patients with stage I disease were analyzed for the prognostic and predictive value of these mutations.

RESULTS

Mutations of EGFR and K-ras genes were detected in 149 (41.1 %) and 23 (6.4 %) of all tumors, and in 122 (47.6 %) and 14 (5.5 %) of stage I tumors, respectively. There were no significant differences in the disease-free survival (DFS) and overall survival (OS) between the EGFR-mutant and wild-type groups. However, the DFS and OS were significantly shorter in patients with K-ras mutations than in those without (5-year DFS: 50.8 vs. 76.9 %, 5-year OS: 70.0 vs. 86.6 %, p < 0.01). A multivariate analysis showed that K-ras mutations were an independent poor prognostic factor. Twenty-four of the 41 patients with recurrent disease after surgery were treated with an EGFR-TKI. Fifteen EGFR-mutant patients treated with an EGFR-TKI had a better prognosis than did the nine EGFR-wild-type patients.

CONCLUSION

The presence of an EGFR gene mutation was a predictive factor for the response to EGFR-TKI treatment in patients with resected stage I adenocarcinoma, but was not a prognostic factor. The presence of a K-ras gene mutation was a poor prognostic factor.

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.

Epidermal growth factor receptor (EGFR) mutation and personalized therapy in advanced nonsmall cell lung cancer (NSCLC)

Before 2009, nonsmall cell lung cancer (NSCLC) was one disease entity treated by cytotoxic chemotherapy that provided a response rate of 20-35 % and a median survival time (MST) of 10-12 months. In 2004, it was found that activated mutations of the epidermal growth factor receptor (EGFR) gene were present in a subset of NSCLC and that tumors with EGFR mutations were highly sensitive to EGFR tyrosine kinase inhibitors (TKI). Four phase III studies (North East Japan (NEJ) 002, West Japan Thoracic Oncology Group (WJTOG) 3405, OPTIMAL, and EUROTAC) prospectively compared TKI (gefitinib or erlotinib) with cytotoxic chemotherapy as first-line therapy in EGFR-mutated NSCLC. These studies confirmed that progression-free survival (PFS) with TKIs (as the primary endpoint) was significantly longer than that with standard chemotherapy (hazard ratio [HR] = 0.16-0.49) from 2009 to 2011. Although the NEJ 002 study showed identical overall survival (OS) between the arms (HR = 0.89), quality of life (QoL) was maintained much longer in patients treated with gefitinib. In conclusion, TKI should be considered as the standard first-line therapy in advanced EGFR-mutated NSCLC. Since 2009, a new step has been introduced in the treatment algorithm for advanced NSCLC.

Real world impact of epidermal growth factor receptor mutation status on treatment patterns in patients with non-small cell lung cancer

BACKGROUND

Epidermal growth factor receptor (EGFR) mutation status is an important predictor of the efficacy of EGFR tyrosine kinase inhibitor (TKI) therapy in patients with non-small cell lung cancer (NSCLC). We evaluated the real impact of EGFR mutation status on chemotherapy patterns of NSCLC patients.

PATIENTS AND METHODS

This is a retrospective cohort study of consecutive advanced NSCLC patients attended at the Samsung Medical Centre in Seoul, Korea, from January 2007 through July 2010. EGFR mutation was analyzed by direct sequencing testing.

RESULTS

Among 1164 patients treated during the study period, 166 (14.3%) were EGFR mutation positive, 275 (23.6%) were mutation negative, and 723 (62.1%) had mutation status unknown. Overall, 605 (52%) received TKI therapy as a first-, second-, or third-line therapy. The proportions of patients receiving TKI therapy among those with positive, negative and unknown EGFR mutation status were 88.0, 46.5, and 45.8%, respectively. After adjustment for other factors, patients with a positive EGFR mutation status (odds ratio [OR] 7.88, 95% CI 4.58, 13.57), and those who were female (OR 2.83, 95% CI 2.04, 3.92) or had poor performance status (OR 1.58, 95% CI 1.13, 2.22) were significantly more likely to receive TKI treatment. Furthermore, the temporal relationship between EGFR mutation reporting and initiation of TKI therapy significantly differed by EGFR mutation status.

CONCLUSION

EGFR mutation status significantly affected the chemotherapy patterns in advanced NSCLC. More widespread EGFR testing and the use of faster and more sensitive mutation tests will result in more timely and appropriate use of TKI therapy in advanced NSCLC.

Personalized medicine for targeted and platinum-based chemotherapy of lung and bladder cancer

The personalized medicine revolution is occurring for cancer chemotherapy. Biomarkers are increasingly capable of distinguishing genotypic or phenotypic traits of individual tumors, and are being linked to the selection of treatment protocols. This review covers the molecular basis for biomarkers of response to targeted and cytotoxic lung and bladder cancer treatment with an emphasis on platinum-based chemotherapy. Platinum derivatives are a class of drugs commonly employed against solid tumors that kill cells by covalent attachment to DNA. Platinum-DNA adduct levels in patient tissues have been correlated to response and survival. The sensitivity and precision of adduct detection has increased to the point of enabling subtherapeutic dosing for diagnostics applications, termed diagnostic microdosing, prior to the initiation of full-dose therapy. The clinical status of this unique phenotypic marker for lung and bladder cancer applications is detailed along with discussion of future applications.

EGFR-targeted therapy for non-small cell lung cancer: focus on EGFR oncogenic mutation

The two essential requirements for pathologic specimens in the era of personalized therapies for non-small cell lung carcinoma (NSCLC) are accurate subtyping as adenocarcinoma (ADC) versus squamous cell carcinoma (SqCC) and suitability for EGFR molecular testing, as well as for testing of other oncogenes such as EML4-ALK and KRAS. Actually, the value of EGFR expressed in patients with NSCLC in predicting a benefit in terms of survival from treatment with an epidermal growth factor receptor targeted therapy is still in debate, while there is a convincing evidence on the predictive role of the EGFR mutational status with regard to the response to tyrosine kinase inhibitors (TKIs).This is a literature overview on the state-of-the-art of EGFR oncogenic mutation in NSCLC. It is designed to highlight the preclinical rationale driving the molecular footprint assessment, the progressive development of a specific pharmacological treatment and the best method to identify those NSCLC who would most likely benefit from treatment with EGFR-targeted therapy. This is supported by the belief that a rationale for the prioritization of specific regimens based on patient-tailored therapy could be closer than commonly expected.

Personalized targeted therapy for lung cancer

Lung cancer has long been recognized as an extremely heterogeneous disease, since its development is unique in every patient in terms of clinical characterizations, prognosis, response and tolerance to treatment. Personalized medicine refers to the use of markers to predict which patient will most likely benefit from a treatment. In lung cancer, the well-developed epidermal growth factor receptor (EGFR) and the newly emerging EML4-anaplastic lymphoma kinase (ALK) are important therapeutic targets. This review covers the basic mechanism of EGFR and EML4-ALK activation, the predictive biomarkers, the mechanism of resistance, and the current targeted tyrosine kinase inhibitors. The efficacy of EGFR and ALK targeted therapies will be discussed in this review by summarizing the prospective clinical trials, which were performed in biomarker-based selected patients. In addition, the revolutionary sequencing and systems strategies will also be included in this review since these technologies will provide a comprehensive understanding in the molecular characterization of cancer, allow better stratification of patients for the most appropriate targeted therapies, eventually resulting in a more promising personalized treatment. The relatively low incidence of EGFR and ALK in non-Asian patients and the lack of response in mutant patients limit the application of the therapies targeting EGFR or ALK. Nevertheless, it is foreseeable that the sequencing and systems strategies may offer a solution for those patients.

Updated overall survival results from a randomized phase III trial comparing gefitinib with carboplatin-paclitaxel for chemo-naïve non-small cell lung cancer with sensitive EGFR gene mutations (NEJ002)

BACKGROUND

NEJ002 study, comparing gefitinib with carboplatin (CBDCA) and paclitaxel (PTX; Taxol) as the first-line treatment for advanced non-small cell lung cancer (NSCLC) harboring an epidermal growth factor receptor (EGFR) mutation, previously reported superiority of gefitinib over CBDCA/PTX on progression-free survival (PFS). Subsequent analysis was carried out mainly regarding overall survival (OS).

MATERIALS AND METHODS

For all 228 patients in NEJ002, survival data were updated in December, 2010. Detailed information regarding subsequent chemotherapy after the protocol treatment was also assessed retrospectively and the impact of some key drugs on OS was evaluated.

RESULTS

The median survival time (MST) was 27.7 months for the gefitinib group, and was 26.6 months for the CBDCA/PTX group (HR, 0.887; P=0.483). The OS of patients who received platinum throughout their treatment (n=186) was not statistically different from that of patients who never received platinum (n=40). The MST of patients treated with gefitinib, platinum, and pemetrexed (PEM) or docetaxel (DOC, Taxotere; n=76) was around 3 years.

CONCLUSIONS

No significant difference in OS was observed between gefitinib and CBDCA/PTX in the NEJ002 study, probably due to a high crossover use of gefitinib in the CBDCA/PTX group. Considering the many benefits and the risk of missing an opportunity to use the most effective agent for EGFR-mutated NSCLC, the first-line gefitinib is strongly recommended.

Biomarkers that currently affect clinical practice: EGFR, ALK, MET, KRAS

New drugs such as pemetrexed, the epidermal growth factor receptor (egfr) tyrosine kinase inhibitors, and the Alk inhibitor crizotinib have recently enabled progress in the management of advanced non-small-cell lung cancer (nsclc). More drugs, especially Met inhibitors, will follow. However, the benefits of these agents are not uniform across the spectrum of nsclc, and optimizing their utility requires some degree of subgrouping of nsclc by the presence or absence of certain biomarkers.The biomarkers of current or imminent value are EGFR and KRAS mutational status, ALK rearrangements, and MET immunohistochemistry. As a predictor of benefit for anti-egfr monoclonal antibodies, EGFR immunohistochemistry is also of potential interest.Some of the foregoing biomarkers (EGFR, ALK, MET) are direct drivers of the malignant phenotype. As such, they are, quite rationally, the direct targets of inhibitory drugs. However, KRAS, while definitely a driver, has resisted attempts at direct pharmacologic manipulation, and its main value might lie in its role as part of an efficient testing algorithm, because KRAS mutations appear to exclude EGFR and ALK mutations. The indirect value of KRAS in determining sensitivity to other targeted agents or to pemetrexed remains controversial. The other biomarkers (EGFR, ALK, MET) may also have indirect value as predictors of sensitivity to chemotherapy in general, to pemetrexed specifically, and to radiotherapy and molecularly targeted agents.These biomarkers have all enabled the co-development of new drugs with companion diagnostics, and they illustrate the paradigm that will govern progress in oncology in the immediate future. However, in nsclc, the acquisition of sufficient biopsy material remains a stubborn obstacle to the evolution of novel targeted therapies.

Association of the expression of mutant epidermal growth factor receptor protein as determined with mutation-specific antibodies in non-small cell lung cancer with progression-free survival after gefitinib treatment

INTRODUCTION

Somatic mutations in the epidermal growth factor receptor (EGFR) gene are associated with an increased response to EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib in patients with non-small cell lung cancer (NSCLC). Although most NSCLC patients with EGFR mutations benefit from EGFR-TKI treatment, the efficacy of such treatment varies among individuals. Molecular markers for prediction of EGFR-TKI treatment efficacy in EGFR mutation-positive NSCLC have not been well defined.

METHODS

The expression of mutant EGFR proteins was quantitated by immunohistochemical analysis with mutation-specific antibodies in tumor specimens from 47 NSCLC patients with postoperative recurrent disease who harbored activating EGFR mutations. The expression score was determined from both the staining intensity and the proportion of tumor tissue expressing the mutant EGFR.

RESULTS

The median progression-free survival after the start of gefitinib treatment was significantly longer in patients with a high score for mutant EGFR expression than in those with a low score (12.2 versus 3.4 months, p < 0.001), whereas no significant difference in median overall survival was apparent between the two groups (24.9 versus 17.7 months, respectively, p = 0.144). This association between the expression score for mutant EGFR and progression-free survival was apparent both in patients with deletions in exon 19 of EGFR and in those with the L858R mutation in exon 21.

CONCLUSIONS

Quantitative analysis of mutant EGFR expression by immunohistochemical analysis with mutation-specific antibodies may predict the efficacy of gefitinib treatment for EGFR mutation-positive NSCLC.

The emerging role of epidermal growth factor receptor (EGFR) inhibitors in first-line treatment for patients with advanced non-small cell lung cancer positive for EGFR mutations

Gefitinib and erlotinib, small-molecule tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR), were the first molecularly targeted agents to become clinically available for the treatment of non-small cell lung cancer (NSCLC). During the course of their clinical development, it has become clear that the substantial clinical benefit associated with EGFR-TKIs is limited to patients harboring activating mutations of EGFR. Accumulating clinical outcomes in patients with EGFR mutation-positive NSCLC treated with EGFR-TKIs support the notion that this group of individuals constitutes a clinically distinct population. These findings have prompted investigations of the potential role of first-line treatment with EGFR-TKIs in molecularly selected patients, with platinum-based doublet chemotherapy currently being the standard of care for most individuals with advanced NSCLC. This review summarizes the results of recent clinical trials of EGFR-TKIs in selected patients and highlights the efficacy of these drugs in first-line treatment as a form of personalized medicine aimed at improving therapy for advanced NSCLC.