Treatment of Advanced Non-Small Cell Lung Cancer with RET Fusions: Reality and Hopes.

RET-selective tyrosine kinase inhibitors (TKIs) selpercatinib and pralsetinib have revolutionized the landscape of RET-positive (RET+) advanced non-small cell lung cancer (NSCLC) treatment, thanks to their efficacy and safety profiles. This class of medications currently represents the standard of care for both naïve and patients that have not received selective RET-TKIs in the first-line setting. However, we presently lack a satisfactory understanding of resistance mechanism developing after selective RET-TKIs usage, as well as a specific treatment for patients progressing on selpercatinib or pralsetinib. Chemotherapy ± immunotherapy is considered as a recommended subsequent second-line regimen in these patients. Therefore, it is of paramount importance to better define and understand the resistance mechanisms triggered by RET-TKIs. With this in mind, the present review article has been conceived to provide a comprehensive overview about RET+ advanced NSCLC, both from a therapeutic and molecular point of view. Besides comparing the clinical outcome achieved in RET+ advanced NSCLC patients after multikinase inhibitors (MKIs) and/or RET-selective TKIs' administration, we focused on the molecular mechanisms accountable for their long-term resistance. Finally, a critical perspective on many of today's most debated issues and concerns is provided, with the purpose of shaping the possible pharmacological approaches for tomorrow's therapies.

Alectinib rescue therapy in advanced ALK rearranged lung adenocarcinoma: a case report.

Alectinib is a highly selective tyrosine kinase inhibitor of anaplastic lymphoma kinase (ALK) that is approved as first-line treatment in adult patients with ALK-positive non-small cell lung cancer (NSCLC) and as second-line in patients previously treated with crizotinib, and has been shown in the literature to significantly prolong progression-free survival compared to chemotherapy in patients with advanced non-small cell lung cancer. The authors describe a clinical case of a 24-year-old woman with malignant massive pleural effusion caused by ALK rearranged pulmonary adenocarcinoma with pleural and pericardial metastasis, in which, despite a dramatic clinical debut, the correct and timely management of the diagnostic and therapeutic path allowed for extraordinary therapeutic success.

Clinicopathologic correlates of first-line pembrolizumab effectiveness in patients with advanced NSCLC and a PD-L1 expression of ≥ 50.

BACKGROUND: Single-agent pembrolizumab represents the standard first-line option for metastatic non-small-cell lung cancer (NSCLC) patients with a PD-L1 (programmed death-ligand 1) expression of ≥ 50%. METHODS: We conducted a multicenter retrospective study aimed at evaluating the clinicopathologic correlates of pembrolizumab effectiveness in patients with treatment-naïve NSCLC and a PD-L1 expression of ≥ 50%. RESULTS: One thousand and twenty-six consecutive patients were included. The objective response rate (ORR) was 44.5% (95% CI 40.2-49.1), while the median progression free survival (PFS) and overall survival (OS) were 7.9 months (95% CI 6.9-9.5; 599 events) and 17.2 months (95% CI 15.3-22.3; 598 censored patients), respectively. ECOG-PS ≥ 2 (p < 0.0001) and bone metastases (p = 0.0003) were confirmed to be independent predictors of a worse ORR. Former smokers (p = 0.0002), but not current smokers (p = 0.0532) were confirmed to have a significantly prolonged PFS compared to never smokers at multivariate analysis. ECOG-PS (p < 0.0001), bone metastases (p < 0.0001) and liver metastases (p < 0.0001) were also confirmed to be independent predictors of a worse PFS. Previous palliative RT was significantly related to a shortened OS (p = 0.0104), while previous non-palliative RT was significantly related to a prolonged OS (p = 0.0033). Former smokers (p = 0.0131), but not current smokers (p = 0.3433) were confirmed to have a significantly prolonged OS compared to never smokers. ECOG-PS (p < 0.0001), bone metastases (p < 0.0001) and liver metastases (p < 0.0001) were also confirmed to be independent predictors of a shortened OS. A PD-L1 expression of ≥ 90%, as assessed by recursive partitioning, was associated with significantly higher ORR (p = 0.0204), and longer and OS (p = 0.0346) at multivariable analysis. CONCLUSION: Pembrolizumab was effective in a large cohort of NSCLC patients treated outside of clinical trials. Questions regarding the effectiveness in clinical subgroups, such as patients with poorer PS and with liver/bone metastases, still remain to be addressed. We confirmed that the absence of tobacco exposure, and the presence of bone and liver metastasis are associated with worse clinical outcomes to pembrolizumab. Increasing levels of PD-L1 expression may help identifying a subset of patients who derive a greater benefit from pembrolizumab monotherapy.

Unproductive Effects of ALK Gene Amplification and Copy Number Gain in Non-Small-Cell Lung Cancer. ALK Gene Amplification and Copy Gain in NSCLC.

Background: The Anaplastic Lymphoma Kinase (ALK) gene is known to be affected by several genetic alterations, such as rearrangement, amplification and point mutation. The main goal of this study was to comprehensively analyze ALK amplification (ALK-A) and ALK gene copy number gain (ALK-CNG) in a large cohort of non-small-cell lung cancer (NSCLC) patients in order to evaluate the effects on mRNA and protein expression. Methods: ALK locus number status was evaluated in 578 NSCLC cases by fluorescence in situ hybridization (FISH). In addition, ALK immunohistochemistry and ALK mRNA in situ hybridization were performed. Results: Out of 578 cases, 17 cases showed ALK-A. In addition, 14 cases presented ALK-CNG and 72 cases presented chromosome 2 polyploidy. None of those carrying ALK-A and -CNG showed either ALK immunohistochemical expression or ALK mRNA expression through in situ hybridization. We observed a high frequency of extra copies of the ALK gene. Conclusions: Our findings demonstrated that ALK-A is not involved in mRNA production and consequently is not involved in protein production; these findings support the hypothesis that ALK-A might not play a role in the pathogenesis of NSCLC, underlining the absence of a specific clinical application.

Prognostic Factors and Biomarkers of Responses to Immune Checkpoint Inhibitors in Lung Cancer.

Manipulation of the immune response is a game changer in lung cancer treatment, revolutionizing management. PD1 and CTLA4 are dynamically expressed on different T cell subsets that can either disrupt or sustain tumor growth. Monoclonal antibodies (MoAbs) against PD1/PDL1 and CTLA4 have shown that inhibitory signals can be impaired, blocking T cell activation and function. MoAbs, used as both single-agents or in combination with standard therapy for the treatment of advanced non-small cell lung cancer (NSCLC), have exhibited advantages in terms of overall survival and response rate; nivolumab, pembrolizumab, atezolizumab and more recently, durvalumab, have already been approved for lung cancer treatment and more compounds are in the pipeline. A better understanding of signaling elicited by these antibodies on T cell subsets, as well as identification of biological determinants of sensitivity, resistance and correlates of efficacy, will help to define the mechanisms of antitumor responses. In addition, the relevance of T regulatory cells (Treg) involved in immune responses in cancer is attracting increasing interest. A major challenge for future research is to understand why a durable response to immune checkpoint inhibitors (ICIs) occurs only in subsets of patients and the mechanisms of resistance after an initial response. This review will explore current understanding and future direction of research on ICI treatment in lung cancer and the impact of tumor immune microenvironment n influencing clinical responses.

Immune Checkpoint Blockade for Advanced NSCLC: A New Landscape for Elderly Patients.

The therapeutic scenario for elderly patients with advanced NSCLC has been limited to radiotherapy and chemotherapy. Recently, a novel therapeutic approach based on targeting the immune-checkpoints has showed noteworthy results in advanced NSCLC. PD1/PD-L1 pathway is co-opted by tumor cells through the expression of PD-L1 on the tumor cell surface and on cells within the microenvironment, leading to suppression of anti-tumor cytolytic T-cell activity by the tumor. The success of immune-checkpoints inhibitors in clinical trials led to rapid approval by the FDA and EMA. Currently, data regarding efficacy and safety of ICIs in older subjects is limited by the poor number of elderly recruited in clinical trials. Careful assessment and management of comorbidities is essential to achieve better outcomes and limit the immune related adverse events in elderly NSCLC patients.

Development of a gene panel for next-generation sequencing of clinically relevant mutations in cell-free DNA from cancer patients.

BACKGROUND: When tumour tissue is unavailable, cell-free DNA (cfDNA)can serve as a surrogate for genetic analyses. Because mutated alleles in cfDNA are usually below 1%, next-generation sequencing (NGS)must be narrowed to target only clinically relevant genes. In this proof-of-concept study, we developed a panel to use in ultra-deep sequencing to identify such mutations in cfDNA. METHODS: Our panel ('SiRe') covers 568 mutations in six genes (EGFR, KRAS, NRAS, BRAF, cKIT and PDGFRα)involved in non-small-cell lung cancer (NSCLC), gastrointestinal stromal tumour, colorectal carcinoma and melanoma. We evaluated the panel performance in three steps. First, we analysed its analytical sensitivity on cell line DNA and by using an artificial reference standard with multiple mutations in different genes. Second, we analysed cfDNA from cancer patients at presentation (n=42), treatment response (n=12) and tumour progression (n=11); all patients had paired tumour tissue and cfDNA previously genotyped with a Taqman-derived assay (TDA). Third, we tested blood samples prospectively collected from NSCLC patients (n=79) to assess the performance of SiRe in clinical practice. RESULTS: SiRe had a high analytical performance and a 0.01% lower limit of detection. In the retrospective series, SiRe detected 40 EGFR, 11 KRAS, 1 NRAS and 5 BRAF mutations (96.8% concordance with TDA). In the baseline samples, SiRe had 100% specificity and 79% sensitivity relative to tumour tissue. Finally, in the prospective series, SiRe detected 8.7% (4/46) of EGFR mutations at baseline and 42.9% (9/21) of EGFR p.T790M in patients at tumour progression. CONCLUSIONS: SiRe is a feasible NGS panel for cfDNA analysis in clinical practice.

The Treatment of a New Entity in Advanced Non-Small Cell Lung Cancer: MET exon 14 Skipping Mutation.

BACKGROUND: MET (MET Proto-Oncogene, Receptor Tyrosine Kinase) exon 14 skipping mutation represents one of the most common MET alterations, accounting for approximately 1-3% of all mutations in advanced lung adenocarcinomas. While until 2020 no specific treatment was available for this subset of patients, as of today, three MET Tyrosine Kinase Inhibitors (TKIs) are currently approved in this setting, namely capmatinib, tepotinib and savolitinib. OBJECTIVE: This article aims to provide an extensive overview of the current therapeutic standard of care for exon 14 skipped advanced Non-Small Cell Lung Cancer (NSCLC) patients, alongside with mentions of the main future challenges and opportunities. CONCLUSION: FDA-approved MET-TKIs currently represent the best option for treating exon 14 skipped advanced NSCLC patients, thanks to their excellent efficacy profile, alongside their manageable safety and tolerability. However, we currently lack specific agents to treat patients progressing on capmatinib or tepotinib, due to a limited understanding of the mechanisms underlying both on- and off-target resistance. In this respect, on-target mutations presently constitute the most explored ones from a mechanistic point of view, and type II MET-TKIs are currently under investigation as the most promising agents capable of overcoming the acquired resistance.

Recently approved and emerging monoclonal antibody immune checkpoint inhibitors for the treatment of advanced non-small cell lung cancer.

INTRODUCTION: CTLA-4/PD-1/PD-L1- directed immune checkpoint inhibitors (ICIs) are one of the standard therapies for the treatment of advanced non-small cell lung cancer (NSCLC). However, some new classes of monoclonal antibodies are emerging as promising therapies for advanced NSCLC. AREAS COVERED: Therefore, this paper aims to provide a comprehensive review of the recently approved as well as emerging monoclonal antibody immune checkpoint inhibitors for the treatment of advanced NSCLC. EXPERT OPINION: Further and larger studies will be needed to explore the promising emerging data on new ICIs. Future phase III trials could allow us to properly assess the role of each immune checkpoints in the wider context of the tumor microenvironment and thus the best new ICIs to use, the best approach and the most effective subset of patients to select.

Prognostic Factors in Advanced Non-Small Cell Lung Cancer Patients Treated with Immunotherapy.

Taking into account the huge epidemiologic impact of lung cancer (in 2020, lung cancer accounted for 2,206,771 of the cases and for 1,796,144 of the cancer-related deaths, representing the second most common cancer in female patients, the most common cancer in male patients, and the second most common cancer in male and female patients) and the current lack of recommendations in terms of prognostic factors for patients selection and management, this article aims to provide an overview of the current landscape in terms of currently available immunotherapy treatments and the most promising assessed prognostic biomarkers, highlighting the current state-of-the-art and hinting at future challenges.

First-line treatment of advanced non-small cell lung cancer with ALK rearrangement: state of the art and future development.

Introduction: Approximately 5% of all diagnosed non-small cell lung cancer (NSCLC) patients harbor a genetic rearrangement between the ALK and EML4 genes, representing a specific molecular, histological and clinical subgroup (ALK+ NSCLC). To date, upfront treatment with ALK-tyrosine-kinase inhibitors (ALK-TKIs) has replaced chemotherapy in the first line setting for this subset of patients with excellent results. However, all treated patients eventually develop acquired resistance mechanisms to these agents (mainly resistance mutations) and experience progression of the disease.Areas covered: This paper provides a comprehensive state-of-the-art review about first-line approved ALK-TKIs, furthermore, it discusses the most promising ALK-TKIs under development designed to overcome resistance mutations and their implications.Expert opinion: Alectinib should currently be regarded as the standard of care for the first-line treatment of ALK+ NSCLC, considering its superior efficacy and safety profile. Regarding developing agents, lorlatinib and ensartinib appear to be the most promising ones, even though the data from their trials are still immature.

The role of antiangiogenic monoclonal antibodies combined to EGFR-TKIs in the treatment of advanced non-small cell lung cancer with activating EGFR mutations: acquired resistance mechanisms and strategies to overcome them.

As of today, only two antiangiogenic monoclonal antibodies plus epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) combinations are FDA and EMA-approved and are recommended by American Society of Clinical Oncology, European Society for Medical Oncology, and National Comprehensive Cancer Network for the first-line treatment of EGFR+ advanced non-small cell lung cancer patients: erlotinib plus bevacizumab and erlotinib plus ramucirumab. However, all treated patients eventually become unresponsive to such drugs, due to several different acquired resistance mechanisms, mainly represented by T790M substitutions and MET amplifications. While osimertinib treatment in T790M+ patients still represents the only approved treatment, MET-TKIs will likely change this status quo in the near future. In fact, existing clinical data strongly support a role for MET-TKI-based combinations in EGFR+ MET-amplified patients, possibly revolutionizing our current treatment algorithm. Chemotherapy plus immunotherapy plus antiangiogenic therapy combinations could also represent another useful addition.

Chemotherapy plus single/double immunotherapy in the treatment of non-oncogene addicted advanced non-small cell lung cancer: where do we stand and where are we going?

INTRODUCTION: Chemo-immunotherapy combinations have revolutionized our treatment algorithm with respect to naïve advanced NSCLC; however, given the great number of developed and approved combinations, the question arises as to which combinations provide the best efficacy and safety. AREAS COVERED: This review assesses and discusses the available data concerning chemo-immunotherapy combinations in the treatment of naïve advanced NSCLC, as well as presenting the most promising data involving combinations currently under investigation. EXPERT OPINION: Pembrolizumab-containing chemo-immunotherapy combinations are associated with the most mature data available and presently represent the standard treatment in clinical practice in naïve advanced NSCLC-affected patients. The nivolumab plus ipilimumab plus short-course chemotherapy combination, more recently approved by regulatory agencies, is an appealing alternative, thanks to the reduced rate of grade 3-5 TRAEs and the limited chemotherapy administration. The new chemo-immunotherapy combinations currently under investigation will help us to better identify both the best immune checkpoints to target and the most effective combinations to administer.

Moving Immune Checkpoint Inhibitors to Early Non-Small Cell Lung Cancer: A Narrative Review.

Lung cancer is the leading cause of cancer-related death worldwide. Since prognosis of early-stage non-small cell lung cancer (NSCLC) remains dismal for common relapses after curative surgery, considerable efforts are currently focused on bringing immunotherapy into neoadjuvant and adjuvant settings. Previously, perioperative chemotherapy showed only a modest but significative improvement in overall survival. The presence of broad tumor neoantigens load at primary tumor prior to surgery as well as the known immunosuppressive status following resection represent the main rationale for immunotherapy in early disease. Several trials have been conducted in recent years, leading to atezolizumab and nivolumab approval in the adjuvant and neoadjuvant setting, respectively, and perioperative immunotherapy in NSCLC remains a field of active clinical and preclinical investigation. Unanswered questions in perioperative therapy in NSCLC include the optimal sequence and timing of chemotherapy and immunotherapy, the potential of combination strategies, the role of predictive biomarkers for patient selection and the choice of useful endpoints in clinical investigation.

Epidermal growth factor receptor exon 20 insertion variants in non-small cell lung cancer patients.

Epidermal growth factor receptor (EGFR) exon 20 insertions occur rarely among different cancer types, with the highest frequency reported among non-small-cell lung cancer (NSCLC) patients, particularly adenocarcinomas (ADCs). Exon 20 insertions fall back in the tyrosine kinase domain, and can be clustered into two principal groups represented by in frame insertions and three to 21 bp (corresponding to 1-7 amino acids) duplications within amino acids 762 and 774. The identification of these alterations is key for an adequate management of NSCLC patients due to the possibility to treat these patients with specific targeted therapies. Next generation sequencing (NGS) technology, able to detect several hotspot gene mutations for different patients simultaneously, is the best detection approach due to its higher sensitivity and specificity compared to other techniques. Here we reviewed the principal biological characteristics, the main detection technologies and treatment options for NSCLC patients harbouring EGFR exon 20 insertions.

RNA-based next-generation sequencing in non-small-cell lung cancer in a routine setting: an experience from an Italian referral center.

Aim: ALK, ROS1, NTRK and RET gene fusions and MET exon 14 skipping alterations represent novel predictive biomarkers for advanced non-small-cell lung cancer (NSCLC). Therefore, testing patients for these genetic variants is crucial for choosing the best selective treatment. Over the last couple of decades, next-generation sequencing (NGS) platforms have emerged as an extremely useful tool for detecting these variants. Materials & methods: In the present study, we report our NGS molecular records produced during a year of diagnostic activity. Results: Overall, our in-house developed NGS workflow successfully analyzed n = 116/131 (88.5%) NSCLC samples. Of these, eight (6.8%) and five (4.3%) out of 116 patients harbored ALK and RET gene rearrangements, respectively: one case harbored ROS1 gene fusion (0.7%). Conclusion: Our results highlight that an RNA-based NGS analysis can reliably detect gene fusion alterations, thereby playing a pivotal role in the management of NSCLC patients.

The role of nivolumab combined to immunotherapy and/or chemotherapy in the first-line treatment of advanced Non Small Cell Lung Cancer.

Introduction: One of the latest breakthroughs in the treatment of advanced Non Small Cell Lung Cancer (NSCLC) is represented by PD-1/PD-L1-targeting Immune Checkpoint Inhibitors (ICIs). However, only a limited subset of advanced NSCLC patients can receive first-line ICI monotherapy (advanced NSCLC patients without driver mutations and with a PD-L1 expression ≥50% or ≥1%) and naïve ICI-respondent patients represent an even more limited subgroup of patients, which eventually experience progression of disease after approximately 7-11 months. Therefore, different strategies are being evaluated to obtain a higher response rate and a more durable clinical response in this setting. A very encouraging one is represented by ICI-combination therapies, i.e. the use of an ICI combined to cytotoxic chemotherapy and/or another immunotherapeutic agent.Areas covered: This paper aims to assess currently available data from trials evaluating nivolumab-based first-line combination therapies.Expert opinion: Nivolumab-based combinations regimens will represent one of the standard treatments for naïve advanced NSCLC patients in a near future. However, in order to fully exploit these combination therapies, additional studies assessing potential predictive and/or prognostic biomarkers are required to better clarify which patients are more likely to benefit from these regimens, alongside with studies investigating safer and more durable second-line treatments.

The treatment of advanced lung adenocarcinoma with activating EGFR mutations.

INTRODUCTION: Lung adenocarcinomas account for approximately 40-50% of all NSCLC (Non-Small Cell Lung Cancer) cases. In addition, lung adenocarcinomas can harbor several different genetic mutations, EGFR (Epidermal Growth Factor Receptor) being the most frequent one, accounting for approximately 5-15% of all the mutations in western patients and for approximately 40-55% in Asian patients; on the other hand, EGFR mutations are uncommon in squamous histology. Approximately 90% of EGFR mutations are represented by exon 19 in-frame deletion and by the L858R exon 21-point mutation, that confer sensitivity to EGFR TKI (Tyrosine Kinase Inhibitors) treatment. AREAS COVERED: The authors comprehensively review the current state of the art with reference to EGFR+ NSCLC treatment and to discuss the possible future developments. EXPERT OPINION: Osimertinib must be considered the preferred first-line agent in EGFR+ advanced NSCLC patients thanks to its superior performances. With respect to acquired resistance mechanisms to osimertinib, the currently ongoing clinical trials will surely help us to better understand and tackle them. Globally, we strongly believe that a biomarker-driven sequential treatment algorithm is key in order to provide personalized, effective and durable therapies in the increasingly complex landscape of EGFR+ advanced NSCLC.

Immune checkpoint inhibitors: a new landscape for extensive stage small cell lung cancer treatment.

Introduction: Landscape of Extensive Stage (ES)-SCLC treatment has been unchanged over the years. Chemotherapy, mostly based on cisplatin and etoposide, remained the standard-of-care for patients with ES-SCLC for almost 40 years. Recently, immune check points inhibitors have emerged marking a turning point for ES-SCLC treatmentAreas covered: Aim of the paper is to discuss ICIs impact on ES-SCLC treatment algorithms, review current clinical trials, and explore future perspectives.Expert opinion: A growing body of evidence supports ICI-containing regimens as a new mainstay of ES-SCLC treatment. Whether subgroups of SCLC patients may have greater survival benefits from ICIs treatment needs to be better defined. Understanding the impact of tumor microenvironment and identifying reliable predictive and/or prognostic biomarkers will be fundamental to move toward a personalized treatment approach leading to improved survival.

Tumor mutational burden on cytological samples: A pilot study.

BACKGROUND: Immune-checkpoint inhibitors (ICIs) represent an important treatment option for patients who have advanced stage non-small cell lung cancer (NSCLC). Currently, evaluation of the expression level of programmed death-ligand 1 (PD-L1) has proven highly successful as a positive predictive biomarker for ICIs. In addition to PD-L1, other promising predictive biomarkers are emerging, including high tumor mutational burden (TMB-H). However, measuring TMB-H remains challenging for several reasons, among which is the difficulty in obtaining adequate tissue material from NSCLC patients. There are no data in the current literature regarding the possibility of adopting cell blocks (CBs) for TMB evaluation; therefore, our goal was to evaluate the feasibility of analyzing TMB on CBs. METHODS: For evaluation of differences in run metric parameters, 8 pairs of histological and CB samples from patients with NSCLC were analyzed using the Oncomine Tumor Mutational Load Assay on Ion Torrent S5 GS next-generation sequencing (NGS) platform. RESULTS: Most CBs (6/8, 75.0%) were successfully analyzed by adopting the broad NGS panel approach. CBs provided results similar to those obtained on histological matched specimens in terms of median total reads (7207048.80 vs 7558817.80), median mapped reads (7075753.83 vs 7513822.00), median read lengths (115.50 vs. 113.00), median percentage of reads on-target (97.49% vs. 98.45%), median average reads per amplicon (454.67 vs 476.14), and median uniformity of amplicon coverage (83.52% vs 84.13%). CONCLUSION: In this pilot study, we demonstrated the technical feasibility of assessing TMB on CBs.