First-SIGNAL: first-line single-agent iressa versus gemcitabine and cisplatin trial in never-smokers with adenocarcinoma of the lung

Can EGFR-TKIs be used in first line treatment for advanced non-small cell lung cancer based on selection according to clinical factors? - A literature-based meta-analysis

BACKGROUND

In the first line treatment of non-small cell lung cancer (NSCLC), several clinical trials have shown that not all NSCLC patients can benefit from treatment with tyrosine kinase inhibitors (TKIs) than receiving chemotherapy. Some trials treated patients with TKI according to their clinical characteristics. A few studies only chose patients with an epidermal growth factor receptor (EGFR) mutation for TKI therapy. We aimed to determine whether patients could be treated with TKIs based on clinical factors in the first-line setting.

METHODS

We performed a meta-analysis of randomized trials involving patients with advanced NSCLC treated with chemotherapy or TKIs by different selections. Efficacy outcomes of interest were the objective response rate (ORR), progression-free survival (PFS) and the overall survival (OS) of each treatment arm.

RESULTS

Four trials enrolled unselected patients, and two trials selected East Asian patients using the clinical factors of gender and smoking history. Five trials chose patients with an EGFR mutation who were randomized for treatment with TKI or chemotherapy. For unselected patients, the risk ratio (RR) of the ORR was 3.52, the hazard ratio (HR) of the PFS was 1.29 and the HR of the OS was 1.35. For the clinically selected patients, the RR of the ORR was 0.64. The HRs of the PFS and OS were 0.83 and 0.92, respectively. The ORR and PFS were better for TKIs than for chemotherapy in patients with an EGFR mutation. The ORR was 0.47, and the HRs of the PFS and OS were 0.36 and 1.00, respectively.

CONCLUSIONS

Advanced NSCLC patients with an EGFR mutation benefit most from TKIs. EGFR-TKI treatment is justified for patients with unknown EGFR status,and those who cannot tolerate chemotherapy owing to age, poor performance status (PS) or other medical conditions, when selected according to clinical factors in the first-line setting.

First- and second-line treatment of non-small-cell lung cancer patients withEGFRmutation-positive tumors

SUMMARY EGFR is a mediator of cell proliferation and is targeted by EGFR tyrosine kinase inhibitors (TKIs) to treat non-small-cell lung cancer (NSCLC). Efficacy of EGFR TKIs (specifically erlotinib and gefitinib) is influenced by mutations in EGFR. We review the evidence for targeted use of EGFR TKIs in the first-line treatment of EGFR mutation-positive NSCLC, considering epidemiology and timing/methodology of diagnosis. First- and second-generation TKIs, and other investigational drugs, also have a role in the second-line treatment of EGFR mutation-positive NSCLC; we discuss this in the context of disease progression and drug resistance. Patients with EGFR mutation-positive tumors should be considered as a separate subpopulation within NSCLC, which is the first step towards individualized treatment of this disease.

Should epidermal growth factor receptor tyrosine kinase inhibitors be considered ideal drugs for the treatment of selected advanced non-small cell lung cancer patients?

An ideal target-based agent for the treatment of cancer patients should fulfil a number of requirements, including the availability of biomarkers to select the target population, superiority over existing treatments and specific advantages in terms of pharmacokinetics and/or metabolism. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib, erlotinib and afatinib, have been investigated in the treatment of non-small cell lung cancer (NSCLC), and to date a large amount of clinical data are available. The activity of EGFR-TKIs was initially investigated in unselected patients leading to unsatisfactory results. However, the discovery that response to EGFR-TKIs is associated with the presence of activating EGFR mutations in NSCLC, has led to the design of clinical trials in which patients were selected on the basis of the EGFR mutational status or of clinical and pathological features that are highly associated with the presence of EGFR mutations. In this respect, several phase III randomized trials have demonstrated that first-line EGFR-TKIs, compared to chemotherapy, is associated with longer progression-free survival, higher response rate, better toxicity profile and quality of life in patients carrying EGFR mutations. Although no survival advantage was demonstrated, all the trials suffered of a high post-progression treatment cross-over, which predictably undermined the results. This review will summarize the current evidence that strongly support the hypothesis that gefitinib, erlotinib and afatinib are ideal drugs for NSCLC patients carrying EGFR mutations.

First-line treatment of EGFR-mutant non-small-cell lung cancer: the role of erlotinib and other tyrosine kinase inhibitors

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) were initially established as second- or third-line treatment of advanced non-small-cell lung cancer (NSCLC). Subsequent studies, including IPASS, OPTIMAL, and EURTAC, have demonstrated that these TKIs are effective first-line therapeutic options in patients with tumors harboring activating mutations in the EGFR gene. The TKIs are better tolerated than conventional chemotherapy, with frequent yet mild side effects such as rash and diarrhea, and rarely interstitial lung disease. Because most patients on TKIs develop resistance due to a variety of mechanisms, the use of TKIs in the acquired-resistance setting and in the setting of earlier-staged cancers is being extensively studied. Here we review the major trials leading to the established use of EGFR TKIs in NSCLC, followed by discussion of recently completed and ongoing trials using the next-generation EGFR inhibitor afatinib.

Crizotinib for the treatment of ALK-rearranged non-small cell lung cancer: a success story to usher in the second decade of molecular targeted therapy in oncology

Crizotinib, an ALK/MET/ROS1 inhibitor, was approved by the U.S. Food and Drug Administration for the treatment of anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC) in August 2011, merely 4 years after the first publication of ALK-rearranged NSCLC. The crizotinib approval was accompanied by the simultaneous approval of an ALK companion diagnostic fluorescent in situ hybridization assay for the detection of ALK-rearranged NSCLC. Crizotinib continued to be developed as an ALK and MET inhibitor in other tumor types driven by alteration in ALK and MET. Crizotinib has recently been shown to be an effective ROS1 inhibitor in ROS1-rearranged NSCLC, with potential future clinical applications in ROS1-rearranged tumors. Here we summarize the heterogeneity within the ALK- and ROS1-rearranged molecular subtypes of NSCLC. We review the past and future clinical development of crizotinib for ALK-rearranged NSCLC and the diagnostic assays to detect ALK-rearranged NSCLC. We highlight how the success of crizotinib has changed the paradigm of future drug development for targeted therapies by targeting a molecular-defined subtype of NSCLC despite its rarity and affected the practice of personalized medicine in oncology, emphasizing close collaboration between clinical oncologists, pathologists, and translational scientists.

Challenges in Implementing Personalized Medicine for Lung Cancer within a National Healthcare System

The traditional approach to the treatment of advanced non-small cell lung cancer (NSCLC) relied on the uniform use of cytotoxic chemotherapy. Over the last eight years, this paradigm of care has been shifting towards the use of molecularly targeted agents. Epidermal growth factor receptor (EGFR) mutations have emerged as an important biomarker for these targeted agents and multiple studies have shown that tyrosine kinase inhibitors (TKI) that inhibit EGFR are superior to traditional chemotherapy in patients possessing an EGFR mutation. Nationally funded health care systems face a number of challenges in implementing these targeted therapies, most related to the need to test for biomarkers that predict likelihood of benefiting from the drug. These obstacles include the challenge of getting a large enough tissue sample, workload of involved specialists, reliability of subtyping in NSCLC, differences in biomarker tests, and the disconnect between the funding of drugs and the related biomarker test. In order to improve patient outcomes, in a national healthcare system, there is a need for governments to accept the changing paradigm, invest in technology and build capacity for molecular testing to facilitate the implementation of improved patient care.

Management of non-small cell lung cancer with oligometastasis

Patients with oligometastatic Non-Small Cell Lung Cancer (NSCLC) present a potential opportunity for curative therapy; however, the challenge remains the definitive treatment of their localized disease and ablation of their limited overt metastatic sites of disease. In selecting patients with oligometastatic NSCLC for definitive therapy, proper staging through radiographic studies, including PET and brain MRI, and the pathologic staging of the mediastinal lymph nodes and potential sites of metastatic disease, are critical. With that in mind, the available literature suggests that in highly selected patients with solitary metastases to the brain, adrenals and other organs, long term survival may be achieved with combined definitive therapy of both the primary lung tumor and the solitary metastatic site.

Treatment paradigms for patients with metastatic non-small-cell lung cancer: first-, second-, and third-line

Metastatic non-small-cell lung cancer (nsclc) is the leading cause of cancer mortality in Canada. Although treatment outcomes in advanced disease remain modest, with paradigm shifts in the approach to treatment, they are steadily improving. Customizing treatment based on histology and molecular typing has become the standard of care. EGFR genotyping and pathology subtyping should be considered routine in new diagnoses of metastatic nsclc. Treatment options for those with somatic EGFR activating mutations include gefitinib until progression, followed by standard chemotherapy. For patients with wild-type EGFR, or in patients whose EGFR genotype is unknown, platinum-based chemotherapy remains the first-line standard, with single-agent chemotherapy as an option for older patients and those who are unfit for platinum-doublet therapy. Patients with nonsquamous histology may receive treatment regimens incorporating pemetrexed or bevacizumab. In patients with squamous cell carcinoma, the latter agents should be avoided because of concerns about enhanced toxicity or decreased efficacy. Second-line chemotherapy is offered to a selected subgroup of patients upon progression and may include pemetrexed in non-squamous histology and docetaxel or erlotinib (or both) in all histologies. Currently, only erlotinib is offered as a third-line option in unselected nsclc patients after failure of first- and second-line chemotherapy. Maintenance therapy is emerging as a new option for patients, as are targeted therapies for particular molecular subtypes of nsclc, such as crizotinib in tumours harbouring the EML4-ALK gene rearrangement.