Biomarkers of minimal residual disease and treatment

Minimal residual disease (MRD) has been defined as a very small numbers of cancer cells that remain in the body after curative treatment. Its presence or absence will ultimately determine prognosis. With the introduction of new technologies the presence of MRD in patients with solid tumours can be detected and characterized. As MRD predicts future relapse, be it early or late treatment failure, in an otherwise asymptomatic patient its treatment and when to start treatment remains to be determined. Thus the concepts of personalized medicine using different biomarkers to classify the biological properties of MRD maybe come possible. Based on this determinations it may be possible to use targeted therapies rather than all patients with the same type of cancer receiving a standard treatment. However, it is important to understand the limitations of the different technologies, what these techniques are detecting and how they may help in the treatment of patients with cancer. The majority of published studies are in patients with metastatic cancer and there are few reports in patients with MRD. In this chapter the concept of MRD, the methods used to detect it and what treatments may be effective based on the biological characteristics of the tumour cells as determined by different biomarkers is reviewed. MRD depends on the phenotypic properties of the tumour cells to survive in their new environment and the anti-tumour immune response. This is a dynamic process and changes with time in the wake of immunosuppression caused by the tumour cells and/or the effects of treatment to select resistant tumour cells. With the use of biomarkers to typify the characteristics of MRD and the development of new drugs a personalized treatment can be designed rather than all patients given the same treatment. Patients who are initially negative for MRD may not require further treatment with liquid biopsies used to monitor the patients during follow-up in order to detect those patients who may become MRD positive. The liquid biopsy used during the follow up of MRD positive patients can be used to detect changes in the biological properties of the tumour cells and thus may need treatment changes to overcome tumour cell resistance.

Exploratory analysis of immunochemotherapy compared to chemotherapy after EGFR-TKI in non-small cell lung cancer patients with EGFR mutation: A multicenter retrospective study

BACKGROUND

Patients with epidermal growth factor receptor (EGFR)-mutated, advanced non-small cell lung cancer have received immunochemotherapy as one of the treatment options after tyrosine kinase inhibitor (TKI) failure.

METHODS

We retrospectively examined EGFR-mutant patients treated with atezolizumab-bevacizumab-carboplatin-paclitaxel (ABCP) therapy or platinum-based chemotherapy (Chemo) after EGFR-TKI therapy at five institutions in Japan.

RESULTS

A total of 57 patients with EGFR mutation were analyzed. The median progression-free survival (PFS) and overall survival (OS) in the ABCP (n = 20) and Chemo (n = 37) were 5.6 and 20.9 months, 5.4 and 22.1 months, respectively (PFS, p = 0.39; OS, p = 0.61). In programmed death-ligand 1 (PD-L1)-positive patients, median PFS in the ABCP group was longer than in the Chemo group (6.9 vs. 4.7 months, p = 0.89). In PD-L1-negative patients, median PFS in the ABCP group was significantly shorter than in the Chemo group (4.6 vs. 8.7 months, p = 0.04). There was no difference in median PFS between the ABCP and Chemo groups in the subgroups of brain metastases, EGFR mutation status, or chemotherapy regimens, respectively.

CONCLUSION

The effect of ABCP therapy and chemotherapy was comparable in EGFR-mutant patients in a real-world setting. The indication for immunochemotherapy should be carefully considered, especially in PD-L1-negative patients.

Liquid Biopsies in Lung Cancer

As lung cancer has the highest cancer-specific mortality rates worldwide, there is an urgent need for new therapeutic and diagnostic approaches to detect early-stage tumors and to monitor their response to the therapy. In addition to the well-established tissue biopsy analysis, liquid-biopsy-based assays may evolve as an important diagnostic tool. The analysis of circulating tumor DNA (ctDNA) is the most established method, followed by other methods such as the analysis of circulating tumor cells (CTCs), microRNAs (miRNAs), and extracellular vesicles (EVs). Both PCR- and NGS-based assays are used for the mutational assessment of lung cancer, including the most frequent driver mutations. However, ctDNA analysis might also play a role in monitoring the efficacy of immunotherapy and its recent accomplishments in the landscape of state-of-the-art lung cancer therapy. Despite the promising aspects of liquid-biopsy-based assays, there are some limitations regarding their sensitivity (risk of false-negative results) and specificity (interpretation of false-positive results). Hence, further studies are needed to evaluate the usefulness of liquid biopsies for lung cancer. Liquid-biopsy-based assays might be integrated into the diagnostic guidelines for lung cancer as a tool to complement conventional tissue sampling.

Clinical Utility and Application of Liquid Biopsy Genotyping in Lung Cancer: A Comprehensive Review

Precision medicine has revolutionized the therapeutic management of cancer patients with a major impact on non-small cell lung cancer (NSCLC), particularly lung adenocarcinoma, where advances have been remarkable. Tissue biopsy, required for tumor molecular testing, has significant limitations due to the difficulty of the biopsy site or the inadequacy of the histological specimen. In this context, liquid biopsy, consisting of the analysis of tumor-released materials circulating in body fluids, such as blood, is increasingly emerging as a valuable and non-invasive biomarker for detecting circulating tumor DNA (ctDNA) carrying molecular tumor signatures. In advanced/metastatic NSCLC, liquid biopsy drives target therapy by monitoring response to treatment and identifying eventual genomic mechanisms of resistance. In addition, recent data have shown a significant ability to detect minimal residual disease in early-stage lung cancer, underlying the potential application of liquid biopsy in the adjuvant setting, in early detection of recurrence, and also in the screening field. In this article, we present a review of the currently available data about the utility and application of liquid biopsy in lung cancer, with a particular focus on the approach to different techniques of analysis for liquid biopsy and a comparison with tissue samples as well as the potential practical uses in early and advanced/metastatic NSCLC.

Minimal residual disease in EGFR-mutant non-small-cell lung cancer

Targeted therapy with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is an effective treatment for EGFR-mutant non-small-cell lung cancer (NSCLC), however most patients invariably relapse after a period of minimal residual disease (MRD). This mini-review explores the mechanistic pathways leading to tumour dormancy, cellular senescence and epigenetic changes involving YAP/TEAD activation. We describe the various approaches of utilising TKIs in combination with agents to intensify initial depth of response, enhance apoptosis and target senescence-like dormancy. This mini-review will also highlight the potential novel therapies under development targeting MRD to improve outcomes for patients with EGFR-mutant NSCLC.

The quantum leap in therapeutics for advanced ALK+ non-small cell lung cancer and pursuit to cure with precision medicine

Since the discovery 15 years ago, we have seen a quantum leap in the treatment and survival for individuals diagnosed with ALK+ lung cancers. Unfortunately however, for most, the diagnosis is made in an incurable circumstance given the late presentation of symptoms. Through a revolutionary wave of therapeutics, individuals may remarkably live over a decade, however many fall short of this milestone, as the molecular profile of this disease is very heterogeneous, reflected in variable survival outcomes. Despite a significant improval in survival and quality of life with ALK-inhibitor monotherapies, now available across multiple-generations, drug resistance and disease relapse remains inevitable, and treatment is offered in an empiric, stepwise, non personalised biomarker informed fashion. A proposed future focus to treating ALK to improve the chronicity of this disease and even promote cure, is to deliver a personalised dynamic approach to care, with rational combinations of drugs in conjunction with local ablative therapies to prevent and constantly proactively alter clonal selection. Such an approach would be informed by precision imaging with MRI-brain and FDG-PETs sequentially, and by regular plasma sampling including for circulating tumour DNA sequencing with personalised therapeutic switches occurring prior to the emergence of radiological and clinical relapse. Such an approach to care will require a complete paradigm shift in the way we approach the treatment of advanced cancer, however evidence to date in ALK+ lung cancers, support this new frontier of investigation.

Real-world efficacy of osimertinib in previously EGFR-TKI treated NSCLC patients without identification of T790M mutation

BACKGROUND

The efficacy of osimertinib in previously EGFR-TKI-treated NSCLC without identification of T790M mutational status remains unclear in real-world practice.

PATIENTS AND METHODS

417 patients had stage III-IV NSCLC harboring EGFR mutation and 154 out of 417 patients receiving osimertinib as ≥ second-line EGFR-TKI were identified. The time to treatment failure and risk of death were analyzed.

RESULTS

Higher risk of death was found in EGFR-mutant patients with age ≥ 65 years, non-adenocarcinoma, no surgery or radiation, non-exon 19 deletion/exon 21 L858R, higher ECOG PS (2-4), PD-L1 expression ≥ 50%, and bone/liver/adrenal metastasis (all p < 0.05). Osimertinib as ≥ second-line TKI in patients with/without identification of T790M revealed lower risk of death compared to first-line first/second generation TKI without subsequent osimertinib (p = 0.0002; 0.0232, respectively). However, osimertinib-treated patients with T790M did not have superior survival than those without (p = 0.2803). A higher risk of treatment failure for osimertinib was found in males, patients with first-line TKI duration ≤ 12 months, BMI drop > 10%, and PD-L1 expression ≥ 50% (All p < 0.05). Nonetheless, osimertinib as ≥ second-line TKI in patients without identification of 790 M did not have higher risk of treatment failure than those with T790M (p = 0.1236).

CONCLUSIONS

This study demonstrates that osimertinib as second line or subsequent TKI in EGFR-TKI-treated patients without identification of T790M revealed lower risk of death compared to first-line first/second generation TKI without subsequent osimertinib, in real-world practice. Additionally, EGFR-mutant patients with PD-L1 expression ≥ 50% had a higher risk of treatment failure for osimertinib and worse overall survival than those with PD-L1 expression < 50%. These results suggest that osimertinib as second line or subsequent TKI may be a potential alternative option for the treatment of patients without identification of T790M and PD-L1 expression ≥ 50% is associated with a significantly poor outcome in patients receiving osimertinib.

Histological Transformation after Acquired Resistance to the Third-Generation EGFR-TKI in Patients with Advanced EGFR-Mutant Lung Adenocarcinoma

Background and Objectives: Third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) is one of the standard-of-care therapies in patients with EGFR-mutant lung adenocarcinoma; however, acquired resistance inevitably developed. Despite the proposition of histological transformation being one of the resistance mechanisms, its incidence and influence on outcome remain unclear. Materials and Methods: This was a retrospective study conducted at Taichung Veterans General Hospital on patients with advanced EGFR-mutant lung adenocarcinoma receiving the third-generation EGFR-TKI. Only patients receiving rebiopsy were included in the analysis. Results: A total of 55 patients were studied. Eight patients (14.5%) showed histological transformation, including three small cell carcinoma, three squamous cell carcinoma, one large cell neuroendocrine carcinoma, and one with a mixture of adenocarcinoma and squamous cell carcinoma components. The median treatment duration of the third-generation EGFR-TKI before rebiopsy was numerically longer in patients with histological transformation than those without (16.0 vs. 10.9 months). Both the overall survival time from the start of third-generation EGFR-TKI initiation (30.8 vs. 41.2 months) and from rebiopsy (6.6 vs. 12.9 months) to mortality were numerically shorter amongst the transformed population. All patients in the transformed group did not respond to the next line of systemic treatment. One patient with histological transformation receiving local treatment for the metastatic site had a longer overall survival. Conclusions: Repeating biopsy to identify histological transformation should be considered in patients with progression to the third-generation EGFR-TKI. Histological transformations could contribute to the acquired resistance with the implication of a worse prognosis. Further studies are needed to determine the optimal therapy for these patients.

Diagnostic Value and Cost-Effectiveness of Next Generation Sequencing-Based Testing for Treatment of Patients with Advanced/Metastatic Non-Squamous Non-Small Cell Lung Cancer in the United States

The study evaluated the diagnostic value and cost-effectiveness of next generation sequencing (NGS)-based testing versus various combinations of single-gene tests (SGTs) for selection of first-line treatment for patients with advanced/metastatic non-squamous non-small cell lung cancer in the United States. A dynamic decision analysis model was developed comparing NGS versus SGT from a payer perspective. Inputs were obtained from published sources and included diagnostic performance, biomarker-positive disease rates, biomarker-directed recommendations for treatment, and survival outcomes. Costs were reported in 2020 US dollars. In the base case, NGS improved the detection of actionable biomarkers by 74.4%, increased the proportion of patients receiving biomarker-driven therapy by 11.9%, and decreased the proportion of patients with biomarker-positive disease receiving non-biomarker-driven first-line treatment by 40.5%. The incremental cost-effectiveness ratio per life-year gained of NGS testing versus SGT was $7224 (excluding post-diagnostic costs); the incremental cost-effectiveness ratio for NGS-directed therapy was $148,786 versus SGT-directed therapy. Sensitivity analyses confirmed the robustness of these findings; survival outcomes and targeted therapy costs had the greatest impact on results. Testing strategies with NGS are more comprehensive in the detection of actionable biomarkers and can improve the proportion of patients receiving biomarker-driven therapies. NGS testing may provide a cost-effective strategy for advanced/metastatic non-squamous non-small cell lung cancer; however, the value of NGS-directed therapy varies by the willingness-to-pay threshold of the decision-maker.

TP53 Co-Mutations in Advanced EGFR-Mutated Non-Small Cell Lung Cancer: Prognosis and Therapeutic Strategy for Cancer Therapy

Lung cancer is the leading cause of cancer-related deaths worldwide. As the most prevalent molecular mutation subtypes in non-small cell lung cancer (NSCLC), EGFR-TKIs are currently a standard first-line therapy for targeting the mutated EGFR in advanced NSCLC patients. However, 20-30% of this subset of patients shows primary resistance to EGFR-TKIs. Patients with co-mutations of EGFR and several other genes have a poor response to EGFR-TKIs, whereas the prognostic and predictive significance of EGFR/TP53 co-mutation in NSCLC patients remains controversial. Meanwhile, little is known about how to choose an optimal therapeutic strategy for this subset of patients. Presently, no drugs targeting TP53 mutations are available on the market, and some p53 protein activators are in the early stage of clinical trials. A combination of EGFR-TKIs with antiangiogenic agents or chemotherapy or other agents might be a more appropriate strategy to tackle the problem. In this review, we describe the prognostic and predictive value of EGFR/TP53 co-mutation in NSCLC patients, investigate the mechanisms of this co-mutation affecting the response to EGFR-TKIs, and further explore optimal regimens effectively to prolong the survival time of the NSCLC patients harboring this co-mutation.

Clinical Applications of Circulating Tumour Cells and Circulating Tumour DNA in Non-Small Cell Lung Cancer-An Update

Despite efforts to improve earlier diagnosis of non-small cell lung cancer (NSCLC), most patients present with advanced stage disease, which is often associated with poor survival outcomes with only 15% surviving for 5 years from their diagnosis. Tumour tissue biopsy is the current mainstream for cancer diagnosis and prognosis in many parts of the world. However, due to tumour heterogeneity and accessibility issues, liquid biopsy is emerging as a game changer for both cancer diagnosis and prognosis. Liquid biopsy is the analysis of tumour-derived biomarkers in body fluids, which has remarkable advantages over the use of traditional tumour biopsy. Circulating tumour cells (CTCs) and circulating tumour DNA (ctDNA) are two main derivatives of liquid biopsy. CTC enumeration and molecular analysis enable monitoring of cancer progression, recurrence, and treatment response earlier than traditional biopsy through a minimally invasive liquid biopsy approach. CTC-derived ex-vivo cultures are essential to understanding CTC biology and their role in metastasis, provide a means for personalized drug testing, and guide treatment selection. Just like CTCs, ctDNA provides opportunity for screening, monitoring, treatment evaluation, and disease surveillance. We present an updated review highlighting the prognostic and therapeutic significance of CTCs and ctDNA in NSCLC.

Comparison of sampling methods for next generation sequencing for patients with lung cancer

Introduction

Success of next generation sequencing (NGS) analysis is becoming indispensable in the treatment of advanced lung cancer. However, the advantages and disadvantages of each sampling method in the NGS analysis have not yet been clarified.

Methods

We compared the success rates of NGS analysis, and DNA and RNA yields for transbronchial biopsy (TBB), endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA), computed tomography (CT)‐guided biopsy, fluid sample, and surgical biopsy for NGS analysis in patients through the lung cancer genomic screening project for individualized medicine (LC‐SCRUM)‐Asia, a nationwide NGS screening project. In case, sufficient samples could not be collected by TBB and EBUS‐TBNA, re‐biopsy (genome re‐biopsy) was performed.

Results

A total of 223 patients were enrolled and success rates of NGS analysis were not different between samples obtained through TBB, EBUS‐TBNA, and CT‐guided biopsy; however, success rates for fluid samples and surgical biopsy samples were significantly higher than those of other methods. The risk of genome re‐biopsy was higher with TBB for centrally located lesions. CT‐guided biopsy yielded more samples but had a lower success rate for analysis of RNA‐based NGS than TBB.

Conclusions

TBB is the mainstay of sampling methods, but for centrally located lesions, EBUS‐TBNA may be a better strategy. For CT‐guided biopsy, the success rate of RNA‐based NGS analysis is low. Fluid samples are expected to yield successful results as surgical biopsy samples, but the latter are better for sample preservation. Determining the optimal method for genome biopsy for each case is important.

Clinical Outcomes of Chemotherapeutic Molecules as Single and Multiple Agents in Advanced Non-Small-Cell Lung Carcinoma (NSCLC) Patients

Background and Objectives: Lung cancer is the second most common cancer in the world. Non-small-cell lung carcinoma (NSCLC) makes up 85% of all lung cancer cases and the majority of patients are diagnosed when the cancer is advanced. Over the years, many anticancer drugs have been designed and introduced into the market to treat patients with advanced NSCLC. This review aims to discuss the comparative therapeutic benefits of conventional chemotherapeutics and other drugs available for treating advanced NSCLC. Materials and Methods: A literature search for first-line treatment of advanced NSCLC was carried out on PubMed and Google Scholar. Objective response rate (ORR) and overall survival were chosen as target endpoints. Results: Monotherapy showed lower treatment endpoints compared to combination therapy. Different combinations of platinum-based doublets demonstrated similar efficacies in treating NSCLC. However, pemetrexed-platinum doublets showed significantly better treatment endpoint in patients with non-squamous NSCLC. Most studies showing the best complete response rate (CRR) utilized epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI), while most studies producing the best overall survival included programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors in their treatment regimens. Conclusions: The findings of this review indicate that targeted therapy using specific inhibitors is now the most promising first-line anticancer treatment available in the market. However, chemotherapy is still effective in treating advanced NSCLC and is viable as a first-line treatment.

Liquid Biopsy for Advanced NSCLC: A Consensus Statement From the International Association for the Study of Lung Cancer

Although precision medicine has had a mixed impact on the clinical management of patients with advanced-stage cancer overall, for NSCLC, and more specifically for lung adenocarcinoma, the advances have been dramatic, largely owing to the genomic complexity and growing number of druggable oncogene drivers. Furthermore, although tumor tissue is historically the "accepted standard" biospecimen for these molecular analyses, there are considerable innate limitations. Thus, liquid biopsy represents a practical alternative source for investigating tumor-derived somatic alterations. Although data are most robust in NSCLC, patients with other cancer types may also benefit from this minimally invasive approach to facilitate selection of targeted therapies. The liquid biopsy approach includes a variety of methodologies for circulating analytes. From a clinical point of view, plasma circulating tumor DNA is the most extensively studied and widely adopted alternative to tissue tumor genotyping in solid tumors, including NSCLC, first entering clinical practice for detection of EGFR mutations in NSCLC. Since the publication of the first International Association for the Study of Lung Cancer (IASLC) liquid biopsy statement in 2018, several additional advances have been made in this field, leading to changes in the therapeutic decision-making algorithm for advanced NSCLC and prompting this 2021 update. In view of the novel and impressive technological advances made in the past few years, the growing clinical application of plasma-based, next-generation sequencing, and the recent Food and Drug and Administration approval in the United States of two different assays for circulating tumor DNA analysis, IASLC revisited the role of liquid biopsy in therapeutic decision-making in a recent workshop in October 2020 and the question of "plasma first" versus "tissue first" approach toward molecular testing for advanced NSCLC. Moreover, evidence-based recommendations from IASLC provide an international perspective on when to order which test and how to interpret the results. Here, we present updates and additional considerations to the previous statement article as a consensus from a multidisciplinary and international team of experts selected by IASLC.

The Impact of Variant Allele Frequency in EGFR Mutated NSCLC Patients on Targeted Therapy

EGFR mutations represent the most common currently targetable oncogenic driver in non-small cell lung cancer. There has been tremendous progress in targeting this alteration over the course of the last decade, and third generation tyrosine kinase inhibitors offer previously unseen survival rates among these patients. Nonetheless, a better understanding is still needed, as roughly a third of patients do not respond to targeted therapy and there is an important heterogeneity among responders. Allelic frequency, or the variant EGFR allele frequency, corresponds to the fraction of sequencing reads harboring the mutation. The allelic fraction is influenced by the proportion of tumor cells in the sample, the presence of copy number alterations but also, most importantly, by the proportion of cells within the tumor that carry the mutation. Mutations that occur early in tumor evolution, often called clonal or truncal, have a higher allelic frequency than late, subclonal mutations, and are more often drivers of cancer evolution and attractive therapeutic targets. Most, but not all, EGFR mutations are clonal. Although an exact estimate of clonal proportion is hard to derive computationally, the allelic frequency is readily available to clinicians and could be a useful surrogate. We hypothesized that tumors with low allelic frequency of the EGFR mutation will respond less favorably to targeted treatment.

Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors and Lung Cancer: History, Epidemiology, and Market Outlook

Lung cancer is a leading cause of death for both men and women. The treatment of lung cancer has been stifled with pessimism for many years. However, molecularly targeted therapies directed at pathologic epidermal growth factor receptor tyrosine kinases have come to market and, with them, a new tone to an old diagnosis. Treatment of lung cancer is a complex science that requires not only anatomical knowledge of the patient but also an understanding of the patient's overall physiologic condition. When patients are treated appropriately, this drug can transform the natural progression of their disease and improve survival. Interestingly, the clinical solidarity of these first-generation tyrosine kinase inhibitors (TKIs) has become the prelude to a second wave of advances in molecular targeting that we can expect to further improve how we classify and treat lung cancers. Cancers that become resistant to epidermal growth factor receptor (EGFR)-specific TKIs through a secondary mutation are likely to be dependent on the activated kinase for their growth and survival. Therefore, discovering a secondary means of inhibiting EGFR T790M may be therapeutically necessary. This has prompted the preclinical and clinical development of second and third-generation kinase inhibitors. Tumor subtypes are also now being identified, potentially allowing patients to be treated with drugs that most benefit their tumor subtype. We used the TriNetX research platform to analyze the rate of patients being prescribed first, second, and third-generation EGFR TKIs and propose a rationale for the trends seen over time.

Efficacy and Safety of Rociletinib Versus Chemotherapy in Patients With EGFR-Mutated NSCLC: The Results of TIGER-3, a Phase 3 Randomized Study

INTRODUCTION

The TIGER-3 (NCT02322281) study was initiated to compare the efficacy and safety of rociletinib, a third-generation EGFR tyrosine kinase inhibitor (TKI) that targets EGFR T790M and common EGFR-activating mutations, versus chemotherapy in patients with NSCLC who progressed on first- or second-generation EGFR TKIs.

METHODS

Patients with advanced or metastatic EGFR-mutated NSCLC with disease progression on standard therapy (previous EGFR TKI and platinum-based chemotherapy) were randomized to oral rociletinib (500 or 625 mg twice daily) or single-agent chemotherapy (pemetrexed, gemcitabine, docetaxel, or paclitaxel).

RESULTS

Enrollment was halted when rociletinib development was discontinued in 2016. Of 149 enrolled patients, 75 were randomized to rociletinib (n = 53: 500 mg twice daily; n = 22: 625 mg twice daily) and 74 to chemotherapy. The median investigator-assessed progression-free survival (PFS) was 4.1 months (95% confidence interval [CI]: 2.6-5.4) in the rociletinib 500-mg group and 5.5 months (95% CI: 1.8-8.1) in the 625-mg group versus 2.5 months (95% CI: 1.4-2.9) in the chemotherapy group. An improved PFS was observed in patients with T790M-positive NSCLC treated with rociletinib (n = 25; 500 mg and 625 mg twice daily) versus chemotherapy (n = 20; 6.8 versus 2.7 mo; hazard ratio = 0.55, 95% CI: 0.28-1.07, p = 0.074). Grade 3 or higher hyperglycemia (24.0%), corrected QT prolongation (6.7%), diarrhea (2.7%), and vomiting (1.3%) were more frequent with rociletinib than chemotherapy (0%, 0%, 1.4%, and 0%, respectively).

CONCLUSIONS

Rociletinib had a more favorable median PFS versus chemotherapy but had higher rates of hyperglycemia and corrected QT prolongation in patients with advanced EGFR-mutated NSCLC who progressed on previous EGFR TKI. Incomplete enrollment prevented evaluation of the primary efficacy end point.

Molecular profiling of advanced non-small cell lung cancer in the era of immunotherapy approach: a multicenter Italian observational prospective study of biomarker screening in daily clinical practice

AIMS

Heterogeneous implementation of molecular tests in current diagnostic algorithm at a European and international level is emerging as a major issue for efficient lung cancer molecular profiling.

METHODS

From May 2017 until October 2017, N=1612 patients referring to 13 Italian institutions were selected, at advanced stage non-small cell lung cancer (NSCLC), and prospectively evaluated. Principal endpoints were: the percentage of diagnoses performed on cytological and histological material, the proportion of requests for epidermal growth factor receptor (EGFR) mutational status, and resistance mutations detected on tissue and/or liquid biopsy samples after first-generation or second-generation tyrosine kinase inhibitors, the proportion of requests for anaplastic lymphoma kinase (ALK) gene rearrangements, ROS proto-oncogene 1 (ROS1) and Kirsten Rat Sarcoma (KRAS) determinations, the proportion of requests for programmed death-ligand1 (PD-L1) evaluation and, finally, the different assays used for the detection of EGFR mutations, ALK and ROS1 gene rearrangements and PD-L1 expression.

RESULTS

Of 1325 patients finally included, only 50.8% requests were related to driver mutations with target agents already available in first-line at that preplanned time, while 49.2% were associated with PD-L1, ROS1, KRAS and others. Multiplex genomic assays (such as next-generation sequencing) were considered by all participating centres.

CONCLUSIONS

To the best of our knowledge, this is the first study in a 'real-life daily practice' involving both pathologists and oncologists evaluating routinely workflow and trends towards improvements in molecular requests. Collected data aim to describe the applied algorithms and evolution of molecular screening for stage IV NSCLC in clinical practice.

Effect of Osimertinib and Bevacizumab on Progression-Free Survival for Patients With Metastatic EGFR-Mutant Lung Cancers: A Phase 1/2 Single-Group Open-Label Trial

Importance

The combination of erlotinib and bevacizumab as initial treatment of epidermal growth factor receptor (EGFR [OMIM 131550])-mutant lung cancers improves progression-free survival (PFS) compared with erlotinib alone. Because osimertinib prolongs PFS compared with erlotinib, this trial was designed to study the combination of osimertinib and bevacizumab as first-line treatment.

Objectives

To determine the safety and tolerability of osimertinib and bevacizumab combination treatment and assess the 12-month PFS of the combination in patients with metastatic EGFR-mutant lung cancers.

Design, Setting, and Particiants

From August 15, 2016, to May 15, 2018, 49 patients with metastatic EGFR-mutant lung cancers were enrolled in this interventional clinical trial, conducted at a single academic cancer center. In the phase 1 portion of the study, a standard 3 + 3 dose de-escalation design was used to determine the maximum tolerated dose of osimertinib and bevacizumab. In the phase 2 portion of the study, patients were treated at the maximum tolerated dose defined in the phase 1 portion. Statistical analysis was performed from August 1 to October 1, 2019.

Interventions

All patients received osimertinib, 80 mg daily, and bevacizumab, 15 mg/kg once every 3 weeks.

Main Outcomes and Measures

The primary objective of the phase 2 portion of the study was to determine the number of patients receiving the combination of osimertinib and bevacizumab who were progression free at 12 months. Secondary end points included overall response rate, median PFS, overall survival, and definition of the toxic effects of the combination treatment.

Results

Among the 49 patients in the study (34 women; median age, 60 years [range, 36-83 years]), PFS at 12 months was 76% (95% CI, 65%-90%). The overall response rate was 80% (95% CI, 67%-91%), and median PFS was 19 months (95% CI, 15-24 months). Of the 6 patients with measurable central nervous system disease, all had a partial or complete central nervous system response. Persistent detection of EGFR-mutant circulating tumor (ct)DNA at 6 weeks was associated with shorter median PFS (clearance at 6 weeks, 16.2 months [95% CI, 13 months to not reached]; and no clearance at 6 weeks, 9.8 months [95% CI, 4 months to not reached]; P = .04) and median overall survival (clearance at 6 weeks, not reached; and no clearance at 6 weeks, 10.1 months [95% CI, 6 months to not reached]; P = .002). Identified mechanisms of resistance included squamous cell transformation (n = 2) pleomorphic transformation (n = 1), and acquired EGFR L718Q (n = 1) and C797S (n = 1) mutations.

Conclusions and Relevance

The combination of osimertinib and bevacizumab met the study's prespecified effectiveness end point. Persistent EGFR-mutant circulating tumor DNA at 6 weeks was associated with early progression and shorter survival. A randomized phase 3 study comparing osimertinib and bevacizumab with osimertinib alone is planned.

Trial Registration

ClinicalTrials.gov Identifier: NCT02803203.

Treating Choroidal Metastases and Improving Vision with Osimertinib in EGFR T790M-Mutated Lung Adenocarcinoma: A Case Report and Review of the Literature

A 41-year-old never-smoking female was diagnosed with epidermal growth factor receptor (EGFR)-mutated T2bN3M1b lung adenocarcinoma with axillary lymph nodes. She complained of blurred vision in the left eye (2/60) and was subsequently found to have a left choroidal metastasis. Treatment with tyrosine kinase inhibitor (TKI) erlotinib was started, and after 1 year of disease stability, she developed unsteadiness and worsening visual disturbance (1/60). Brain imaging showed 24 new brain metastases, which were treated with Gamma Knife stereotactic radiosurgery. An enlarging axillary lymph node was biopsied, which identified the T790M mutation, and she commenced the novel TKI osimertinib. Three weeks later, her choroidal lesion had regressed from 3.1 mm to 2.2 mm, and after 2 months of osimertinib, her visual acuity had improved to 6/9. At the last follow-up 8 months after initiation of osimertinib, her choroidal metastasis remains stable, and visual acuity has improved to 6/6. Evidence suggests that osimertinib's efficacy in treating cerebral metastases is superior to that of chemotherapy and other EGFR-TKIs (gefitinib and erlotinib); however, the literature is sparse with regards to the use of osimertinib for the treatment of intraocular disease. In this case, the need for intense daily radiation treatment with its associated toxicities was negated, and as such we propose that osimertinib may be a promising treatment for choroidal metastasis secondary to EGFR-mutated lung adenocarcinoma.

Development of Liposomal Vesicles for Osimertinib Delivery to EGFR Mutation-Positive Lung Cancer Cells

Osimertinib (OSI, AZD9291), is a third-generation, irreversible tyrosine kinase inhibitor (TKI) of the epidermal growth factor receptor (EGFR) that selectively inhibits both EGFR-TKI–sensitizing and EGFR T790M resistance mutations. OSI has been approved as a first-line treatment of EGFR-mutant lung cancer and for metastatic EGFR T790M-mutant non-small cell lung cancer. Liposome-based delivery of OSI can provide a new formulation of the drug that can be administered via alternative delivery routes (intravenous, inhalation). In this manuscript, we report for the first time development and characterization of liposomal OSI formulations with diameters of ca. 115 nm. Vesicles were composed of phosphatidylcholines with various saturation and carbon chain lengths, cholesterol and pegylated phosphoethanolamine. Liposomes were loaded with OSI passively, resulting in a drug being dissolved in the phospholipid matrix or actively via remote-loading leading to the formation of OSI precipitate in the liposomal core. Remotely loaded liposomes were characterized by nearly 100% entrapment efficacy and represent a depot of OSI. Passively-loaded vesicles released OSI following the Peppas-Sahlin model, in a mechanism combining drug diffusion and liposome relaxation. OSI-loaded liposomes composed of l-α-phosphatidylcholine (egg-PC) demonstrated a higher toxicity in non-small lung cancer cells with EGFR T790M resistance mutation (H-1975) when compared with free OSI. Developed OSI formulations did not show antiproliferative activity in vitro in healthy lung epithelial cells (MRC-5) without the EGFR mutation.

Targeted Therapies in Early Stage NSCLC: Hype or Hope?

Non-small-cell lung cancer (NSCLC) represents roughly 85% of lung cancers, with an incidence that increases yearly across the world. The introduction in clinical practice of several new and more effective molecules has led to a consistent improvement in survival and quality of life in locally advanced and metastatic NSCLC. In particular, oncogenic drivers have indeed transformed the therapeutic algorithm for NSCLC. Nearly 25% of patients are diagnosed in an early stage when NSCLC is still amenable to radical surgery. In spite of this, five-year survival rates for fully resected early stage remains rather disappointing. Adjuvant chemotherapy has shown a modest survival benefit depending on the stage, but more than half of patients relapse. Given this need for improvement, over the last years different targeted therapies have been evaluated in early-stage NSCLC with no survival benefit in unselected patients. However, the identification of reliable predictive biomarkers to these agents in the metastatic setting, the design of molecularly-oriented studies, and the availability of novel potent and less toxic agents opened the way for a novel era in early stage NSCLC treatment. In this review, we will discuss the current landscape of targeted therapeutic options in early NSCLC.

Mutant Proteomics of Lung Adenocarcinomas Harboring Different EGFR Mutations

Epidermal growth factor receptor EGFR major driver mutations may affect downstream molecular networks and pathways, which would influence treatment outcomes of non-small cell lung cancer (NSCLC). This study aimed to unveil profiles of mutant proteins expressed in lung adenocarcinomas of 36 patients harboring representative driver EGFR mutations (Ex19del, nine; L858R, nine; no Ex19del/L858R, 18). Surprisingly, the orthogonal partial least squares discriminant analysis performed for identified mutant proteins demonstrated the profound differences in distance among the different EGFR mutation groups, suggesting that cancer cells harboring L858R or Ex19del emerge from cellular origins different from L858R/Ex19del-negative cells. Weighted gene coexpression network analysis, together with over-representative analysis, identified 18 coexpressed modules and their eigen proteins. Pathways enriched differentially for both the L858R and Ex19del mutations included carboxylic acid metabolic process, cell cycle, developmental biology, cellular responses to stress, mitotic prophase, cell proliferation, growth, epithelial to mesenchymal transition (EMT), and immune system. The IPA causal network analysis identified the highly activated networks of PARPBP, HOXA1, and APH1 under the L858R mutation, whereas those of ASGR1, APEX1, BUB1, and MAPK10 were highly activated under the Ex19del mutation. Interestingly, the downregulated causal network of osimertinib intervention showed the highest significance in overlap p-value among most causal networks predicted under the L858R mutation. We also identified the causal network of MAPK interacting serine/threonine kinase 1/2 (MNK1/2) highly activated differentially under the L858R mutation. Tumor-suppressor AMOT, a component of the Hippo pathways, was highly inhibited commonly under both L858R and Ex19del mutations. Our results could identify disease-related protein molecular networks from the landscape of single amino acid variants. Our findings may help identify potential therapeutic targets and develop therapeutic strategies to improve patient outcomes.

Osimertinib Improves Overall Survival in Patients With EGFR-Mutated NSCLC With Leptomeningeal Metastases Regardless of T790M Mutational Status

INTRODUCTION

Osimertinib, a third-generation EGFR tyrosine kinase inhibitor, efficiently penetrates the blood-brain barrier. This study explored whether treatment with osimertinib leads to improved overall survival (OS) for patients with EGFR-mutated NSCLC with leptomeningeal metastases (LM) compared with those not treated with osimertinib.

METHODS

From October 2008 to October 2019, patients with EGFR-mutated NSCLC and cytologically confirmed LM were retrospectively analyzed for OS according to osimertinib treatment and T790M mutational status. The OS was defined as the time from the diagnosis of LM to death.

RESULTS

For the 351 patients with LM included in the analysis, the median OS (mOS) was 8.1 months (95% confidence interval [CI]: 7.2-9.0). T790M mutation was detected in 88 of 197 patients tested, and a total of 110 patients were treated with osimertinib after LM. No difference in mOS according to T790M mutational status (10.1 mo [95% CI: 4.31-15.82] versus 9.0 [95% CI: 6.81-11.21], p = 0.936) was found. Nevertheless, patients treated with osimertinib had a superior OS of 17.0 months (95% CI: 15.13-18.94) compared with those not treated with osimertinib who had a mOS of 5.5 months (95% CI: 4.34-6.63), regardless of T790M mutational status (hazard ratio: 0.36 [95% CI: 0.28-0.47], p < 0.001). This was also considerably longer even than the mOS of 8.7 months (95% CI: 7.01-10.39) of those who were never treated with osimertinib but had first- or second-generation EGFR tyrosine kinase inhibitors.

CONCLUSIONS

Osimertinib is a promising treatment option for EGFR-mutated NSCLC with LM regardless of T790M mutational status.

Disease-related cellular protein networks differentially affected under different EGFR mutations in lung adenocarcinoma

It is unclear how epidermal growth factor receptor EGFR major driver mutations (L858R or Ex19del) affect downstream molecular networks and pathways. This study aimed to provide information on the influences of these mutations. The study assessed 36 protein expression profiles of lung adenocarcinoma (Ex19del, nine; L858R, nine; no Ex19del/L858R, 18). Weighted gene co-expression network analysis together with analysis of variance-based screening identified 13 co-expressed modules and their eigen proteins. Pathway enrichment analysis for the Ex19del mutation demonstrated involvement of SUMOylation, epithelial and mesenchymal transition, ERK/mitogen-activated protein kinase signalling via phosphorylation and Hippo signalling. Additionally, analysis for the L858R mutation identified various pathways related to cancer cell survival and death. With regard to the Ex19del mutation, ROCK, RPS6KA1, ARF1, IL2RA and several ErbB pathways were upregulated, whereas AURK and GSKIP were downregulated. With regard to the L858R mutation, RB1, TSC22D3 and DOCK1 were downregulated, whereas various networks, including VEGFA, were moderately upregulated. In all mutation types, CD80/CD86 (B7), MHC, CIITA and IFGN were activated, whereas CD37 and SAFB were inhibited. Costimulatory immune-checkpoint pathways by B7/CD28 were mainly activated, whereas those by PD-1/PD-L1 were inhibited. Our findings may help identify potential therapeutic targets and develop therapeutic strategies to improve patient outcomes.

Much has changed in the last decade except overall survival: A Swiss single center analysis of treatment and survival in patients with stage IV non-small cell lung cancer

BACKGROUND

Molecular therapies for cancers with targetable driver mutations and immunotherapies have revolutionized treatment of non-small cell lung cancer (NSCLC) during the last decade. International treatment guidelines began integrating targeted therapies in 2009 and immunotherapies in 2015. The aim of this study was to examine whether the benefits described for these new therapies in pivotal phase III trials have been translated to a real world patient population.

PATIENTS AND METHODS

Data from all consecutive patients diagnosed with stage IV NSCLC diagnosed at a community hospital in Switzerland between 2007 and 2018 were analyzed. Three groups of patients were compared, namely patients diagnosed before 2009 (group 1), between 2009 and 2015 (introduction of targeted therapies, group 2) and after 2015 (introduction of immunotherapies, group 3). The primary outcome was overall survival (OS). Time to treatment failure was a secondary outcome. Both endpoints were estimated using the Kaplan Meyer method and compared by log-rank test.

RESULTS

408 patients were included. Patient characteristics were similar in the three groups. Median OS in groups 1, 2, and 3 was 9.8 (95% CI, 6.2 to 13.4), 9.9 (95% CI, 7.6 to 12.1) and 8.6 (95% CI, 6.6 to 10.5) months, respectively (p = 0.5). Across groups patients treated with targeted- and immunotherapies had a significantly better outcome than those treated with chemotherapy or best supportive care (p<0.001). Nevertheless, OS remained unchanged between groups despite adequate molecular testing and integration of targeted- and immunotherapies. Over time, the patient population got more morbid with respect to tumor burden (p = 0.02) and co-morbidities (p = 0.02).

CONCLUSIONS

While selected subgroups of patients may benefit from new therapies, outcome in this unselected population of patients with stage IV NSCLC treated in daily practice has not improved over the last decade.

Routine-Dose and High-Dose Icotinib in Patients with Advanced Non-Small Cell Lung Cancer Harboring EGFR Exon 21-L858R Mutation: the Randomized, Phase II, INCREASE Trial

PURPOSE

Our primary purpose is to explore safety and efficacy of high-dose icotinib in comparison with routine-dose icotinib in patients with non-small cell lung cancer (NSCLC) harboring 21-L858R mutation.

PATIENTS AND METHODS

Patients with treatment-naïve, EGFR-mutant (21-L858R or exon 19 deletion at 2:1) NSCLC were enrolled. Patients with 21-L858R mutation were randomized to receive routine-dose icotinib (125 mg, thrice daily; L858R-RD) or high-dose icotinib (250 mg, thrice daily; L858R-HD), whereas patients with exon 19 deletion received only routine-dose icotinib (19-Del-RD) until progression, death, or unacceptable toxicity. The primary endpoint was median progression-free survival (mPFS), assessed by an independent review committee.

RESULTS

From May 2015 to November 2017, 253 patients (86 in L858R-RD; 90 in L858R-HD; and 77 in 19-Del-RD) were enrolled. The mPFS in L858R-HD group was similar to that in 19-Del-RD group (12.9 months and 12.5 months, respectively) and was significantly longer than that in L858R-RD group [12.9 months vs. 9.2 months, hazard ratio (HR): 0.75; 95% confidence interval (CI), 0.53-1.05]. A longer but statistically nonsignificant mPFS was observed between 19-Del-RD and L858R-RD groups (12.5 months vs. 9.2 months, HR: 0.80; 95% CI, 0.57-1.13). A higher objective response rate (ORR) was observed in L858R-HD group compared with L858R-RD group (73% vs. 48%), also between 19-Del-RD and L858R-RD groups (75% vs. 48%). Similar incidences of grade 3/4 toxicities were observed among the three treatment groups.

CONCLUSIONS

High-dose icotinib improved mPFS and ORR in patients with NSCLC harboring 21-L858R mutation with acceptable tolerability, which could be a new therapeutic option for this patient population.

Heregulin expression and its clinical implication for patients with EGFR-mutant non-small cell lung cancer treated with EGFR-tyrosine kinase inhibitors

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are standard therapy for EGFR-mutant non-small cell lung cancer (NSCLC). Preclinically, HER3 ligand heregulin induces resistance to EGFR-TKIs, whereas the pan-human EGFR family inhibitor afatinib remains effective. Here, we examined whether soluble heregulin levels have clinical implications for EGFR-mutant NSCLC treated with EGFR-TKIs. Soluble heregulin was immunologically measured in plasma from EGFR-mutant NSCLC patients. Cutoff values were determined by 1-year PFS ROC curve. The relationship between soluble heregulin and PFS following EGFR-TKI therapy was analyzed by Cox proportional hazards model. Seventy-three patients were enrolled: 44 were treated with 1^st-generation and 29 with 2^nd-generation EGFR-TKIs. Soluble heregulin levels varied (range: 274-7,138 pg/mL, median: 739 pg/mL). Among patients treated with 1^st-generation EGFR-TKIs, those with high heregulin (n = 20, >800 pg/mL) had a tendency for shorter PFS than those with low heregulin (n = 24, <800 pg/mL), with median PFS of 322 and 671 days, respectively. Cox proportional hazards model also indicated a trend toward resistance against 1^st-generation EGFR-TKIs (HR: 1.825, 95% CI: 0.865-4.318) but not against 2^nd-generation EGFR-TKIs. Soluble heregulin potentially correlates with resistance to EGFR-TKIs but not 2^nd-generation EGFR-TKIs in patients with EGFR-mutant NSCLC.

Tyrosine Kinase Inhibitors for the Treatment of EGFR Mutation-Positive Non-Small-Cell Lung Cancer: A Clash of the Generations

The availability of 3 generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) with different pharmacologic characteristics and clinical profiles has provided oncologists with a potentially confusing choice for the treatment of EGFR mutation-positive non-small-cell lung cancer. Although recent head-to-head clinical trials have demonstrated improved efficacy with second-generation (ie, afatinib, dacomitinib) and third-generation (ie, osimertinib) TKIs compared with the first-generation TKIs (eg, erlotinib, gefitinib), acquired resistance has been inevitable, regardless of which agent has been chosen as first-line therapy. Thus, the potential availability of subsequent treatment options is an important consideration. Recent data have demonstrated that osimertinib confers an overall survival benefit compared with first-generation EGFR TKIs, and dacomitinib has shown an overall survival benefit compared with gefitinib in an exploratory analysis. However, the relative benefits of different sequential EGFR-TKI regimens, especially those involving second- and third-generation agents, have remained uncertain and require prospective evaluation. Few such data currently exist to inform treatment choices. In the present review, we examined the pharmacologic characteristics and current clinical data for EGFR TKIs, including emerging information on the molecular mechanisms of resistance across the different generations of TKIs. Given the uncertainties regarding the optimal treatment choice, we have focused on the factors that might help determine the treatment decisions, such as efficacy and safety in patient subgroups. We also discussed the emerging real-world data, which have provided some insights into the benefits of sequential regimens in everyday clinical practice.