Efficacy of ALK inhibitors on NSCLC brain metastases: A systematic review and pooled analysis of 21 studies

Combined use of radiotherapy and tyrosine kinase inhibitors in the management of metastatic non-small cell lung cancer: A literature review

The approval of tyrosine kinase inhibitors (TKIs) as first-line agents has revolutionised treatment of patients diagnosed with advanced non-small cell lung cancer (NSCLC) harboring targetable mutations, adding substantial overall survival (OS) benefit, compared to chemotherapy. However, the efficacy of these agents is inevitably diminished at a point in the disease course, either because of cellular resistance-mechanisms or due to affected pharmacokinetics, like low-central nervous system penetration. The aim of this article is to review existing evidence on the combined use of EGFR (epidermal growth factor)- or ALK (anaplastic lymphoma kinase)-specific TKIs and radiotherapy (RT) in advanced NSCLC setting, as an attempt to delay or overcome TKI-resistance and thus, to expand the time period during which patients derive benefit from a given line of targeted therapy. At present, combining RT with EGFR- or ALK-TKIs in the management of advanced, oncodriver-mutated NSCLC has shown quite promising results, with regards to PFS and OS, rendering prolongation of the TKI-derived benefit feasible, with generally tolerable toxicity. Future studies to confirm the observed efficacy and clarify possible safety issues as well as the appropriate treatment sequence and target volumes are needed, especially in the rapidly-evolving era of newer-generation TKIs.

Tyrosine kinase inhibitors in cancers: Treatment optimization - Part I

A multitude of TKI has been developed and approved targeting various oncogenetic alterations. While these have provided improvements in efficacy compared with conventional chemotherapies, resistance to targeted therapies occurs. Mutations in the kinase domain result in the inability of TKI to inactivate the protein kinase. Also, gene amplification, increased protein expression and downstream activation or bypassing of signalling pathways are commonly reported mechanisms of resistance. Improved understanding of mechanisms involved in TKI resistance has resulted in the development of new generations of targeted agents. In a race against time, the search for new, more potent and efficient drugs, and/or combinations of drugs, remains necessary as new resistance mechanisms to the latest generation of TKI emerge. This review examines the various generations of TKI approved to date and their common mechanisms of resistance, focusing on TKI targeting BCR-ABL, epidermal growth factor receptor, anaplastic lymphoma kinase and BRAF/MEK tyrosine kinases.

A Review of the Molecular Determinants of Therapeutic Response in Non-Small Cell Lung Cancer Brain Metastases

Lung cancer is a leading cause of cancer-related morbidity and mortality worldwide. Metastases in the brain are a common hallmark of advanced stages of the disease, contributing to a dismal prognosis. Lung cancer can be broadly classified as either small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). NSCLC represents the most predominant histology subtype of lung cancer, accounting for the majority of lung cancer cases. Recent advances in molecular genetics, coupled with innovations in small molecule drug discovery strategies, have facilitated both the molecular classification and precision targeting of NSCLC based on oncogenic driver mutations. Furthermore, these precision-based strategies have demonstrable efficacy across the blood-brain barrier, leading to positive outcomes in patients with brain metastases. This review provides an overview of the clinical features of lung cancer brain metastases, as well as the molecular mechanisms that drive NSCLC oncogenesis. We also explore how precision medicine-based strategies can be leveraged to improve NSCLC brain metastases.

Effectiveness of ALK inhibitors in treatment of CNS metastases in NSCLC patients

Metastases to the central nervous system (CNS) in patients with non-small cell lung cancer constitute an extremely difficult clinical problem, and their occurrence is associated with a poor prognosis. Due to the existence of the blood-brain barrier (BBB) and the action of proteins responsible for the transport of drugs, e.g. P-glycoprotein (P-gp), the penetration of drugs into the CNS is insufficient. Until recently, the only method of CNS metastases treatment was radiotherapy and neurosurgery. The advancement of molecular biology allowed discover targets for molecularly targeted therapies. One of targets is abnormal anaplastic lymphoma kinase, which results from the rearrangement of the ALK gene in patients with non-small cell lung cancer (NSCLC). ALK rearrangement occurs in only about 4.5% of NSCLC patients, but its presence favors brain metastases. The ALK inhibitors (ALKi) were modified to obtain molecules with high ability to penetrate into the CNS. This was achieved by modifying the structure of individual molecules, which became, inter alia, less substrates for P-gp. These modifications caused that less than 10% of patients experience progression in CNS during new ALK inhibitors treatment. This review summarizes the knowledge about the action of BBB, the pharmacodynamics and pharmacokinetics of ALKi, with particular emphasis on their ability to penetrate the CNS and the intracranial activity of individual drugs from different generations of ALK inhibitors.

Strategies to overcome resistance to ALK inhibitors in non-small cell lung cancer: a narrative review

Background and Objective

Anaplastic lymphoma kinase (ALK) rearrangements are detected in 3-7% of advanced non-small cell lung cancer (NSCLC). There are currently 5 U.S Food and Drug Administration (FDA)-approved ALK tyrosine kinase inhibitors (TKIs) for the treatment of patients with ALK-positive lung cancer in the advanced/metastatic disease setting. Despite these advances, most patients with ALK-positive lung cancer who are treated with ALK TKI therapy ultimately experience disease progression due to various mechanisms of drug resistance. In this review, we discuss strategies to address acquired therapeutic resistance to ALK inhibition, novel agents and combinatorial strategies in development for both on and off-target resistance, and some emerging approaches to prolong response to ALK inhibitors.

Methods

We performed a search of peer-reviewed literature in the English language, conference abstracts, and trial registrations from the MEDLINE (Ovid), Embase (Elsevier), and CENTRAL (Cochrane Library) databases and major international oncology meetings up to August 2022. We then screened for studies describing interventions to overcome ALK resistance based on review of each title and abstract.

Key Content and Findings

For patients with oligo-progression, treatment may include maintaining the same systemic treatment beyond progression while adding local therapies to progressing lesions. Strategies to combat ALK TKI resistance mediated by on-target resistance mechanisms include 4th generation TKIs (TPX-0131, NVL-655) and proteolysis-targeting chimeras (PROTACs) currently in development. While for those patients who develop tumor progression due to off-target (ALK independent) resistance, options may include combination therapies targeting ALK and other downstream or parallel pathways, novel antibody drug conjugates, or combinations of ALK inhibitors with chemotherapy and immunotherapy. Lastly, other potential strategies being explored in the clinic include circulating tumor DNA (ctDNA) surveillance to monitor for molecular mediators of drug resistance prior to frank progression on imaging studies and utilization of ALK TKIs in the adjuvant and neoadjuvant settings.

Conclusions

Strategies to overcome resistance to currently available ALK inhibitors are urgently needed. Given the variety of resistance mechanisms, tailormade approaches are required for disease control.

Comparative Efficacy of ALK Inhibitors for Treatment-Naïve ALK-Positive Advanced Non-Small Cell Lung Cancer with Central Nervous System Metastasis: A Network Meta-Analysis

Central nervous system (CNS) metastases and acquired resistance complicate the treatment of anaplastic lymphoma kinase (ALK) rearrangement-positive (ALK-p) advanced non-small cell lung cancer (NSCLC). Thus, this review aimed to provide a comprehensive overview of brain metastasis, acquired resistance, and prospects for overcoming these challenges. A network meta-analysis of relevant phase III randomized controlled trials was performed to compare the efficacies of multiple ALK inhibitors by drug and generation in overall patients with ALK-p untreated advanced NSCLC and a subgroup of patients with CNS metastases. The primary endpoint was progression-free survival (PFS). Generation-specific comparison results showed that third-generation ALK inhibitors were significantly more effective than second-generation ALK inhibitors in prolonging the PFS of the subgroup of patients with CNS metastases. Drug-specific comparison results demonstrated that lorlatinib was the most effective in prolonging PFS, followed by brigatinib, alectinib, ensartinib, ceritinib, crizotinib, and chemotherapy. While lorlatinib was superior to brigatinib for PFS in the overall patient population, no significant difference between the two was found in the subgroup of patients with CNS metastases. These results can serve as a foundation for basic, clinical, and translational research and guide clinical oncologists in developing individualized treatment strategies for patients with ALK-p, ALK inhibitor-naive advanced NSCLC.

The role of targeted therapy and immune therapy in the management of non-small cell lung cancer brain metastases

Brain metastases are a significant source of morbidity and mortality in patients with non-small cell lung cancer. Historically, surgery and radiation therapy have been essential to maintaining disease control within the central nervous system due to poorly penetrant conventional chemotherapy. With the advent of targeted therapy against actionable driver mutations, there is potential to control limited and asymptomatic intracranial disease and delay local therapy until progression. In this review paper, intracranial response rates and clinical outcomes to biological and immune therapies are summarized from the literature and appraised to assist clinical decision making and identify areas for further research. Future clinical trials ought to prioritize patient-centered quality of life and neurocognitive measures as major outcomes and specifically stratify patients based on mutational marker status, disease burden, and symptom acuity.

Towards a single-assay approach: a combined DNA/RNA sequencing panel eliminates diagnostic redundancy and detects clinically-relevant fusions in neuropathology

Since the introduction of integrated histological and molecular diagnoses by the 2016 World Health Organization (WHO) Classification of Tumors of the Nervous System, an increasing number of molecular markers have been found to have prognostic significance in infiltrating gliomas, many of which have now become incorporated as diagnostic criteria in the 2021 WHO Classification. This has increased the applicability of targeted-next generation sequencing in the diagnostic work-up of neuropathology specimens and in addition, raises the question of whether targeted sequencing can, in practice, reliably replace older, more traditional diagnostic methods such as immunohistochemistry and fluorescence in-situ hybridization. Here, we demonstrate that the Oncomine Cancer Gene Mutation Panel v2 assay targeted-next generation sequencing panel for solid tumors is not only superior to IHC in detecting mutation in IDH1/2 and TP53 but can also predict 1p/19q co-deletion with high sensitivity and specificity relative to fluorescence in-situ hybridization by looking at average copy number of genes sequenced on 1p, 1q, 19p, and 19q. Along with detecting the same molecular data obtained from older methods, targeted-next generation sequencing with an RNA sequencing component provides additional information regarding the presence of RNA based alterations that have diagnostic significance and possible therapeutic implications. From this work, we advocate for expanded use of targeted-next generation sequencing over more traditional methods for the detection of important molecular alterations as a part of the standard diagnostic work up for CNS neoplasms.

Survival Prediction After Neurosurgical Resection of Brain Metastases: A Machine Learning Approach

BACKGROUND

Current prognostic models for brain metastases (BMs) have been constructed and validated almost entirely with data from patients receiving up-front radiotherapy, leaving uncertainty about surgical patients.

OBJECTIVE

To build and validate a model predicting 6-month survival after BM resection using different machine learning algorithms.

METHODS

An institutional database of 1062 patients who underwent resection for BM was split into an 80:20 training and testing set. Seven different machine learning algorithms were trained and assessed for performance; an established prognostic model for patients with BM undergoing radiotherapy, the diagnosis-specific graded prognostic assessment, was also evaluated. Model performance was assessed using area under the curve (AUC) and calibration.

RESULTS

The logistic regression showed the best performance with an AUC of 0.71 in the hold-out test set, a calibration slope of 0.76, and a calibration intercept of 0.03. The diagnosis-specific graded prognostic assessment had an AUC of 0.66. Patients were stratified into regular-risk, high-risk and very high-risk groups for death at 6 months; these strata strongly predicted both 6-month and longitudinal overall survival ( P < .0005). The model was implemented into a web application that can be accessed through http://brainmets.morethanml.com .

CONCLUSION

We developed and internally validated a prediction model that accurately predicts 6-month survival after neurosurgical resection for BM and allows for meaningful risk stratification. Future efforts should focus on external validation of our model.

Real world use of radiation for newly diagnosed brain metastases in ALK-positive lung cancer receiving a first line ALK inhibitor

PURPOSE

Management paradigms now allow systemic targeted drugs before central nervous system (CNS)-directed radiotherapy (RT) in selected asymptomatic patients with non-small cell lung cancer (NSCLC) with brain metastases (BM). We aim to quantify how novel targeted agents with improved CNS activity, such as second-generation ALK inhibitors (e.g. alectinib), might impact the role of CNS-directed RT.

METHODS AND MATERIALS

This retrospective, observational, real world patterns of care study used a nationwide electronic health record-derived de-identified longitudinal database. A random sample of patients with ALK+ advanced NSCLC and BM on first-line ALK-inhibitor monotherapy between January 1, 2014 and August 31, 2019 were included. Using an index date of the first instance of BM, the outcome was brain-directed local treatment within four months. Trends over time were reported and tested using multivariable modified Poisson regression with robust error variance, including an indicator of in or after 2017 (when alectinib was approved).

RESULTS

Of 352 patients, 146 had BM. 104 received CNS-directed local therapy and 42 did not. The majority (89.4%) were treated with RT alone. Of those receiving RT, stereotactic radiosurgery (SRS) monotherapy was the most common (53%) followed by whole brain radiotherapy (WBRT) alone (39%). On multivariable analysis, those patients who had their first BM in or after 2017 had a decreased rate of receiving local BM treatment versus those prior to 2017 with an adjusted incidence rate ratio (aIRR) 0.63 (95% confidence interval [CI]: 0.41-0.95; p=0.026). We found no change in the proportion of BM treated with WBRT in or after 2017 vs before (aIRR = 0.70; 95% CI: 0.24-2.06; p = 0.517).

CONCLUSIONS

We found decreasing use of CNS-directed RT in patients with NSCLC with new BM on first-line ALK inhibitors. Clinical outcomes for these patients require continued investigation as physicians may be increasingly comfortable deferring upfront local therapy for BM in lieu of novel targeted agents with improved CNS activity.

Lorlatinib as a treatment for ALK-positive lung cancer

Lorlatinib, a third-generation ALK tyrosine kinase inhibitor, has been approved as a treatment for ALK-positive lung cancer. This review provides information regarding the pharmacology and clinical features of lorlatinib, including its efficacy and associated adverse events. Pivotal clinical trials are discussed along with the current status of lorlatinib as a treatment for ALK-positive lung cancer and future therapeutic challenges.

ASCEND-7: Efficacy and Safety of Ceritinib Treatment in Patients with ALK-Positive Non-Small Cell Lung Cancer Metastatic to the Brain and/or Leptomeninges

PURPOSE

Central nervous system metastases are a prominent cause of morbidity and mortality in patients with ALK-positive (ALK+) non-small cell lung cancer (NSCLC). The phase II ASCEND-7 (NCT02336451) study was specifically designed to assess the efficacy and safety of the ALK inhibitor (ALKi) ceritinib in patients with ALK+ NSCLC metastatic to the brain and/or leptomeninges.

PATIENTS AND METHODS

Patients with active brain metastases were allocated to study arms 1 to 4 based on prior exposure to an ALKi and/or prior brain radiation (arm 1: prior radiotherapy/ALKi-pretreated; arm 2: no radiotherapy/ALKi-pretreated; arm 3: prior radiotherapy/ALKi-naïve; arm 4: no radiotherapy/ALKi-naïve). Arm 5 included patients with leptomeningeal carcinomatosis. Patients received ceritinib 750 mg once daily (fasted condition). Primary endpoint was investigator-assessed whole-body overall response rate (ORR) per RECIST v1.1. Secondary endpoints included disease control rate (DCR) and intracranial/extracranial responses.

RESULTS

Per investigator assessment, in arms 1 (n = 42), 2 (n = 40), 3 (n = 12), and 4 (n = 44), respectively: whole-body ORRs [95% confidence interval (CI)] were 35.7% (21.6-52.0), 30.0% (16.6-46.5), 50.0% (21.1-78.9), and 59.1% (43.2-73.7); whole-body DCR (95% CI): 66.7% (50.5-80.4), 82.5% (67.2-92.7), 66.7% (34.9-90.1), and 70.5% (54.8-83.2); intracranial ORRs (95% CI): 39.3% (21.5-59.4), 27.6% (12.7-47.2), 28.6% (3.7-71.0), and 51.5% (33.5-69.2). In arm 5 (n = 18), whole-body ORR was 16.7% (95% CI, 3.6-41.4) and DCR was 66.7% (95% CI, 41.0-86.7). Paired cerebrospinal fluid and plasma sampling revealed that ceritinib penetrated the human blood-brain barrier.

CONCLUSIONS

Ceritinib showed antitumor activity in patients with ALK+ NSCLC with active brain metastases and/or leptomeningeal disease, and could be considered in the management of intracranial disease. See related commentary by Murciano-Goroff et al., p. 2477.

Targeting ALK Rearrangements in NSCLC: Current State of the Art

Anaplastic lymphoma kinase (ALK) alterations in non-small cell lung cancer (NSCLC) can be effectively treated with a variety of ALK-targeted drugs. After the approval of the first-generation ALK inhibitor crizotinib which achieved better results in prolonging the progression-free survival (PFS) compared with chemotherapy, a number of next-generation ALK inhibitors have been developed including ceritinib, alectinib, brigatinib, and ensartinib. Recently, a potent, third-generation ALK inhibitor, lorlatinib, has been approved by the Food and Drug Administration (FDA) for the first-line treatment of ALK-positive (ALK+) NSCLC. These drugs have manageable toxicity profiles. Responses to ALK inhibitors are however often not durable, and acquired resistance can occur as on-target or off-target alterations. Studies are underway to explore the mechanisms of resistance and optimal treatment options beyond progression. Efforts have also been undertaken to develop further generations of ALK inhibitors. This review will summarize the current situation of targeting the ALK signaling pathway.

Population-based high-throughput toxicity screen of human iPSC-derived cardiomyocytes and neurons

In this study, we establish a population-based human induced pluripotent stem cell (hiPSC) drug screening platform for toxicity assessment. After recruiting 1,000 healthy donors and screening for high-frequency human leukocyte antigen (HLA) haplotypes, we identify 13 HLA-homozygous "super donors" to represent the population. These "super donors" are also expected to represent at least 477,611,135 of the global population. By differentiating these representative hiPSCs into cardiomyocytes and neurons we show their utility in a high-throughput toxicity screen. To validate hit compounds, we demonstrate dose-dependent toxicity of the hit compounds and assess functional modulation. We also show reproducible in vivo drug toxicity results using mouse models with select hit compounds. This study shows the feasibility of using a population-based hiPSC drug screening platform to assess cytotoxicity, which can be used as an innovative tool to study inter-population differences in drug toxicity and adverse drug reactions in drug discovery applications.

Evaluation of Lorlatinib Cerebrospinal Fluid Concentrations in Relation to Target Concentrations for ALK Inhibition

Lorlatinib is a third‐generation, brain‐penetrant anaplastic lymphoma kinase (ALK) and c‐ros oncogene 1 (ROS1) tyrosine kinase inhibitor (TKI) with robust intracranial activity in patients with ALK‐ or ROS1‐positive non‐small cell lung cancer (NSCLC). Data from the ongoing open‐label, single‐arm, multicenter, phase‐1/2 study of lorlatinib in patients with metastatic ALK‐ or ROS1‐positive NSCLC were used to further investigate the potential brain penetration of lorlatinib. Patients received escalating lorlatinib doses (10–200 mg once daily or 35–100 mg twice daily) or the approved dosing (100 mg daily). Plasma was collected from all patients, and cerebrospinal fluid (CSF) was collected at baseline and during the study from 5 patients with suspected or confirmed leptomeningeal carcinomatosis or carcinomatous meningitis. For those 5 patients, lorlatinib concentrations ranged from 2.64 to 125 ng/mL in the CSF and from 12.7 to 457 ng/mL in the plasma; free plasma concentrations ranged from 4.318 to 155.385 ng/mL. The CSF/free plasma ratio was 0.77 (R² = 0.96 and P < .001). Using a post‐hoc population pharmacokinetic model, the average steady‐state unbound plasma concentration of lorlatinib was derived and the CSF concentration was estimated for all patients. Known minimum efficacy concentrations (C_eff) for wild‐type and mutated (L1196M and G1202R) ALK were used to derive central nervous system (CNS) C_eff. Estimated CNS concentrations exceeded the derived CNS C_eff values in all patients for wild‐type ALK and the ALK L1196M mutation, and in 35.8% of patients for the ALK G1202R mutation. Projected lorlatinib CNS concentrations were consistent with the high intracranial response rates reported in clinical trials and provide further evidence of the potent CNS penetration of lorlatinib.

A preclinical model of patient-derived cerebrospinal fluid circulating tumor cells for experimental therapeutics in leptomeningeal disease from melanoma

BACKGROUND

Leptomeningeal disease (LMD) occurs as a late complication of several human cancers and has no rationally designed treatment options. A major barrier to developing effective therapies for LMD is the lack of cell-based or preclinical models that recapitulate human disease. Here, we describe the development of in vitro and in vivo cultures of patient-derived cerebrospinal fluid circulating tumor cells (PD-CSF-CTCs) from patients with melanoma as a preclinical model to identify exploitable vulnerabilities in melanoma LMD.

METHODS

CSF-CTCs were collected from melanoma patients with melanoma-derived LMD and cultured ex vivo using human meningeal cell-conditioned media. Using immunoassays and RNA-sequencing analyses of PD-CSF-CTCs, molecular signaling pathways were examined and new therapeutic targets were tested for efficacy in PD-CSF-CTCs preclinical models.

RESULTS

PD-CSF-CTCs were successfully established both in vitro and in vivo. Global RNA analyses of PD-CSF-CTCs revealed several therapeutically tractable targets. These studies complimented our prior proteomic studies highlighting IGF1 signaling as a potential target in LMD. As a proof of concept, combining treatment of ceritinib and trametinib in vitro and in vivo demonstrated synergistic antitumor activity in PD-CSF-CTCs and BRAF inhibitor-resistant melanoma cells.

CONCLUSIONS

This study demonstrates that CSF-CTCs can be grown in vitro and in vivo from some melanoma patients with LMD and used as preclinical models. These models retained melanoma expression patterns and had signaling pathways that are therapeutically targetable. These novel models/reagents may be useful in developing rationally designed treatments for LMD.

A Need for More Molecular Profiling in Brain Metastases

As local disease control improves, the public health impact of brain metastases (BrM) continues to grow. Molecular features are frequently different between primary and metastatic tumors as a result of clonal evolution during neoplasm migration, selective pressures imposed by systemic treatments, and differences in the local microenvironment. However, biomarker information in BrM is not routinely obtained despite emerging evidence of its clinical value. We review evidence of discordance in clinically actionable biomarkers between primary tumors, extracranial metastases, and BrM. Although BrM biopsy/resection imposes clinical risks, these risks must be weighed against the potential benefits of assessing biomarkers in BrM. First, new treatment targets unique to a patient's BrM may be identified. Second, as BrM may occur late in a patient's disease course, resistance to initial targeted therapies and/or loss of previously identified biomarkers can occur by the time of occult BrM, rendering initial and other targeted therapies ineffective. Thus, current biomarker data can inform real-time treatment options. Third, biomarker information in BrM may provide useful prognostic information for patients. Appreciating the importance of biomarker analyses in BrM tissue, including how it may identify specific drivers of BrM, is critical for the development of more effective treatment strategies to improve outcomes for this growing patient population.

Retrospective Real-World Outcomes for Patients With ALK-Rearranged Lung Cancer Receiving ALK Receptor Tyrosine Kinase Inhibitors

Introduction

This study explored the use, safety, and efficacy of initial use of an ALK-inhibiting targeted therapy (ALK tyrosine kinase inhibitor [TKI]) in patients with ALK-rearranged NSCLC in a population-based, real-world clinical population within the province of Alberta, Canada.

Methods

Demographic, clinical, treatment, and outcome data of the patients with advanced or metastatic ALK-rearranged NSCLC receiving their first ALK TKI between 2014 and 2019 were included in the analysis.

Results

A total of 92 patients with ALK-rearranged NSCLC treated with ALK TKI (78% crizotinib, 22% alectinib) were identified. In the ALK-rearranged cohort, 1-year survival rate was 73% and median overall survival (OS) and progression-free survival (PFS) were 48.5 months and 17.0 months, respectively. An objective response rate of 49% was observed, and adverse events were reported in 70% of the patients, primarily of low grade (84%). Case-matched comparison to patients with ALK-wildtype disease treated with cytotoxic chemotherapy revealed the benefit of ALK TKI in the context of an ALK rearrangement (ALK-rearranged versus ALK-wildtype) (median post-treatment initiation OS: 46.8 versus 14.2 mo, p < 0.001). Outcomes, measured from the time of ALK TKI initiation, differed by Eastern Cooperative Oncology Group (ECOG) (ECOG < 2 versus ECOG ≥ 2) (median OS: not reached versus 6.8 mo, p < 0.001; median PFS 17.6 versus 7.4 mo, p = 0.02), disease presentation (relapsed versus de novo) (median PFS: 30.8 versus 15.0 mo, p = 0.04), and brain metastasis onset (brain metastases development during ALK TKI versus baseline brain metastases) (not reached versus 12.8 mo, p = 0.04).

Conclusions

Clinical trials have firmly established that ALK TKIs are safe, well tolerated, and effective; these findings reveal that their impact in a real-world setting is just as profound. The availability and use of ALK TKI therapies contribute to the impressive gains in survival experienced by contemporary patients with ALK-rearranged disease, rendering patients with this oncodriven form of NSCLC among the longest surviving patients with lung cancer.

The Liquid Biopsy for Lung Cancer: State of the Art, Limitations and Future Developments

Simple Summary

During the development and progression of lung tumors, processes such as necrosis and vascular invasion shed tumor cells or cellular components into various fluid compartments. Liquid biopsies consist of obtaining a bodily fluid, typically peripheral blood, in order to isolate and investigate these shed tumor constituents. Circulating tumor cells (CTCs) are one such constituent, which can be isolated from blood and can act as a diagnostic aid and provide valuable prognostic information. Liquid-based biopsies may also have a potential future role in lung cancer screening. Circulating tumor DNA (ctDNA) is found in small quantities in blood and, with the recent development of sensitive molecular and sequencing technologies, can be used to directly detect actionable genetic alterations or monitor for resistance mutations and guide clinical management. While potential benefits of liquid biopsies are promising, they are not without limitations. In this review, we summarize the current state and limitations of CTCs and ctDNA and possible future directions.

Abstract

Lung cancer is a leading cause of cancer-related deaths, contributing to 18.4% of cancer deaths globally. Treatment of non-small cell lung carcinoma has seen rapid progression with targeted therapies tailored to specific genetic drivers. However, identifying genetic alterations can be difficult due to lack of tissue, inaccessible tumors and the risk of complications for the patient with serial tissue sampling. The liquid biopsy provides a minimally invasive method which can obtain circulating biomarkers shed from the tumor and could be a safer alternative to tissue biopsy. While tissue biopsy remains the gold standard, liquid biopsies could be very beneficial where serial sampling is required, such as monitoring disease progression or development of resistance mutations to current targeted therapies. Liquid biopsies also have a potential role in identifying patients at risk of relapse post treatment and as a component of future lung cancer screening protocols. Rapid developments have led to multiple platforms for isolating circulating tumor cells (CTCs) and detecting circulating tumor DNA (ctDNA); however, standardization is lacking, especially in lung carcinoma. Additionally, clonal hematopoiesis of uncertain clinical significance must be taken into consideration in genetic sequencing, as it introduces the potential for false positives. Various biomarkers have been investigated in liquid biopsies; however, in this review, we will concentrate on the current use of ctDNA and CTCs, focusing on the clinical relevance, current and possible future applications and limitations of each.

Blood First Assay Screening Trial (BFAST) in Treatment-Naive Advanced or Metastatic NSCLC: Initial Results of the Phase 2 ALK-Positive Cohort

INTRODUCTION

The Blood First Assay Screening Trial is an ongoing open-label, multicohort study, prospectively evaluating the relationship between blood-based next-generation sequencing (NGS) detection of actionable genetic alterations and activity of targeted therapies or immunotherapy in treatment-naive advanced or metastatic NSCLC. We present data from the ALK-positive cohort.

METHODS

Patients aged more than or equal to 18 years with stage IIIB or IV NSCLC and ALK rearrangements detected by blood-based NGS using hybrid capture technology (FoundationACT) received alectinib 600 mg twice daily. Asymptomatic or treated central nervous system (CNS) metastases were permitted. Primary end point was investigator-assessed objective response rate (ORR; Response Evaluation Criteria in Solid Tumors version 1.1). Secondary end points were independent review facility-assessed ORR, duration of response, progression-free survival (PFS), overall survival, and safety. Exploratory end points were investigator-assessed ORR in patients with baseline CNS metastases and relationship between circulating biomarkers and response.

RESULTS

In total, 2219 patients were screened and blood-based NGS yielded results in 98.6% of the cases. Of these, 119 patients (5.4%) had ALK-positive disease; 87 were enrolled and received alectinib. Median follow-up was 12.6 months (range: 2.6-18.7). Confirmed ORR was 87.4% (95% confidence interval [CI]: 78.5-93.5) by investigator and 92.0% (95% CI: 84.1-96.7) by independent review facility. Investigator-confirmed 12-month duration of response was 75.9% (95% CI: 63.6-88.2). In 35 patients (40%) with baseline CNS disease, investigator-assessed ORR was 91.4% (95% CI: 76.9-98.2). Median PFS was not reached; 12-month investigator-assessed PFS was 78.4% (95% CI: 69.1-87.7). Safety data were consistent with the known tolerability profile of alectinib.

CONCLUSIONS

These results reveal the clinical application of blood-based NGS as a method to inform clinical decision-making in ALK-positive NSCLC.

Neurosurgical resection for locally recurrent brain metastasis

BACKGROUND

In patients with locally recurrent brain metastases (LRBMs), the role of (repeat) craniotomy is controversial. This study aimed to analyze long-term oncological outcomes in this heterogeneous population.

METHODS

Craniotomies for LRBM were identified from a tertiary neuro-oncological institution. First, we assessed overall survival (OS) and intracranial control (ICC) stratified by molecular profile, prognostic indices, and multimodality treatment. Second, we compared LRBMs to propensity score-matched patients who underwent craniotomy for newly diagnosed brain metastases (NDBM).

RESULTS

Across 180 patients, median survival after LRBM resection was 13.8 months and varied by molecular profile, with >24 months survival in ALK/EGFR+ lung adenocarcinoma and HER2+ breast cancer. Furthermore, 102 patients (56.7%) experienced intracranial recurrence; median time to recurrence was 5.6 months. Compared to NDBMs (n = 898), LRBM patients were younger, more likely to harbor a targetable mutation and less likely to receive adjuvant radiation (p < 0.05). After 1:3 propensity matching stratified by molecular profile, LRBM patients generally experienced shorter OS (hazard ratio 1.67 and 1.36 for patients with or without a mutation, p < 0.05) but similar ICC (hazard ratio 1.11 in both groups, p > 0.20) compared to NDBM patients with similar baseline. Results across specific molecular subgroups suggested comparable effect directions of varying sizes.

CONCLUSIONS

In our data, patients with LRBMs undergoing craniotomy comprised a subgroup of brain metastasis patients with relatively favorable clinical characteristics and good survival outcomes. Recurrent status predicted shorter OS but did not impact ICC. Craniotomy could be considered in selected, prognostically favorable patients.

An ocular lesion of unknown aetiology

Can you diagnose this patient with vision problems? https://bit.ly/3vGe5qy.

NPM-ALK: A Driver of Lymphoma Pathogenesis and a Therapeutic Target

Simple Summary

Anaplastic lymphoma kinase (ALK) is a tyrosine kinase associated with Anaplastic Large Cell lymphoma (ALCL) through oncogenic translocations mainly NPM-ALK. Chemotherapy is effective in ALK(+) ALCL patients and induces remission rates of approximately 80%. The remaining patients do not respond to chemotherapy and some patients have drug-resistant relapses. Different classes of ALK tyrosine kinase inhibitors (TKI) are available but used exclusively for EML4-ALK (+) lung cancers. The significant toxicities of most ALK inhibitors explain the delay in their use in pediatric ALCL patients. Some ALCL patients do not respond to the first generation TKI or develop an acquired resistance. Combination therapy with ALK inhibitors in ALCL is the current challenge.

Abstract

Initially discovered in anaplastic large cell lymphoma (ALCL), the ALK anaplastic lymphoma kinase is a tyrosine kinase which is affected in lymphomas by oncogenic translocations, mainly NPM-ALK. To date, chemotherapy remains a viable option in ALCL patients with ALK translocations as it leads to remission rates of approximately 80%. However, the remaining patients do not respond to chemotherapy and some patients have drug-resistant relapses. It is therefore crucial to identify new and better treatment options. Nowadays, different classes of ALK tyrosine kinase inhibitors (TKI) are available and used exclusively for EML4-ALK (+) lung cancers. In fact, the significant toxicities of most ALK inhibitors explain the delay in their use in ALCL patients, who are predominantly children. Moreover, some ALCL patients do not respond to Crizotinib, the first generation TKI, or develop an acquired resistance months following an initial response. Combination therapy with ALK inhibitors in ALCL is the current challenge.

Gap between pediatric and adult approvals of molecular targeted drugs

To clarify the approval status of molecular targeted antineoplastic drugs in the United States (U.S.), the European Union (E.U.), and Japan (JP), we checked the status of pediatric indications according to the package insert of each drug. A total of 103 drugs were approved for adult patients in at least one of the three regions whereas only 19 drugs were approved for pediatric patients. Sixty-six of 103 drugs (64.1%) had adult indications in the U.S., the E.U., and JP, whereas only three drugs had pediatric indications in all three regions. Abnormalities in six genes (NRAS, ABL1, JAK2, KIT, ALK and BRAF) were common in childhood cancers as well as adult cancers, for which at least one approved drug could be a potentially actionable drug. Although there were 16 candidate drugs that had adult indications for these abnormalities, only three drugs (18.8%) had pediatric indications. We confirmed that there were few molecular targeted antineoplastic drugs with pediatric indications in the U.S., the E.U., and JP compared with the number of approved drugs for adults. Drugs targeting genomic abnormalities which were common in both adult and pediatric cancers were considered to be good candidates for expansion of their indication for pediatric patients.

Lorlatinib in previously treated anaplastic lymphoma kinase-rearranged non-small cell lung cancer: Japanese subgroup analysis of a global study

Lorlatinib is a potent, brain‐penetrant, third‐generation anaplastic lymphoma kinase (ALK)/ROS proto‐oncogene 1 (ROS1) tyrosine kinase inhibitor (TKI) that is active against most known resistance mutations. This is an ongoing phase 1/2, multinational study (NCT01970865) investigating the efficacy, safety and pharmacokinetics of lorlatinib in ALK‐rearranged/ROS1‐rearranged advanced non–small cell lung cancer (NSCLC) with or without intracranial (IC) metastases. Because patterns of ALK TKI use in Japan differ from other regions, we present a subgroup analysis of Japanese patients. Patients were enrolled into six expansion (EXP) cohorts based on ALK/ROS1 mutation status and treatment history. The primary endpoint was the objective response rate (ORR) and the IC‐ORR based on independent central review. Secondary endpoints included pharmacokinetic evaluations. At data cutoff, 39 ALK‐rearranged/ROS1‐rearranged Japanese patients were enrolled across the six expansion cohorts; all received lorlatinib 100 mg once daily. Thirty‐one ALK‐rearranged patients previously treated with ≥1 ALK TKI (EXP2 to EXP5) were evaluable for ORR and 15 were evaluable for IC‐ORR. The ORR and the IC‐ORR for Japanese patients in EXP2‐5 were 54.8% (95% confidence interval [CI]: 36.0‐72.7) and 46.7% (95% CI: 21.3‐73.4), respectively. Among patients who had received prior alectinib only (EXP3B), the ORR was 42.9%; 95% CI: 9.9‐81.6). The most common treatment‐related adverse event (TRAE) was hypercholesterolemia (79.5%). Hypertriglyceridemia was the most common grade 3/4 TRAE (25.6%). Single‐dose and multiple‐dose pharmacokinetic profiles among Japanese patients were similar to those in non–Japanese patients. Lorlatinib showed clinically meaningful responses and IC responses among ALK‐rearranged Japanese patients with NSCLC who received ≥1 prior ALK TKI, including meaningful responses among those receiving prior alectinib only. Lorlatinib was generally well tolerated.

68-months progression-free survival with crizotinib treatment in a patient with metastatic ALK positive lung adenocarcinoma and sarcoidosis: A case report

INTRODUCTION

Lung cancer still ranks first among the most common and most lethal cancers today. The most common subtype is non-small cell lung cancer, and in this group, adenocarcinoma has the worst prognosis. EGFR, ROS1 and ALK-EML4 gene fusion mutations are common in non-small cell lung cancer.

CASE REPORT

A 62-year-old non-smoker patient applied in February 2014 for purulent sputum and pain in the chest. Computed tomography revealed a 39x33 mm mass in the right hilum, multiple parenchymal nodules in the bilateral lung and mediastinal multiple enlarged lymph nodes. The patient was admitted to the lung adenocarcinoma as a result of a biopsy from the mass in the hilum, and sarcoidosis was diagnosed by mediastinal lymph node biopsy.

MANAGEMENT & OUTCOME

After 4 cycles of carboplatin-pemetrexed for the first line treatment, progression was detected. The patient did not have EGFR and ROS1 mutations. The patient with positive ALK fusion mutation started crizotinib treatment in July 2014. The patient's last response assessment was in March 2020, with 68-progression-free disease with crizotinib. No toxicity was observed except for Grade 1 weakness. No dose changes were made. The patient is still being followed up without brain metastasis under the treatment of crizotinib.

DISCUSSION

In this article, we wanted to share our experience of crizotinib in a 68-months progression-free survival in a 62-years old non-smoking female patient with metastatic lung adenocarcinoma who is also diagnosed with sarcoidosis.

Medical management of brain metastases

The development of brain metastases occurs in 10–20% of all patients with cancer. Brain metastases portend poor survival and contribute to increased cancer mortality and morbidity. Despite multimodal treatment options, which include surgery, radiotherapy, and chemotherapy, 5-year survival remains low. Besides, our current treatment modalities can have significant neurological comorbidities, which result in neurocognitive decline and a decrease in a patient’s quality of life. However, innovations in technology, improved understanding of tumor biology, and new therapeutic options have led to improved patient care. Novel approaches in radiotherapy are minimizing the neurocognitive decline while providing the same therapeutic benefit. In addition, advances in targeted therapies and immune checkpoint inhibitors are redefining the management of lung and melanoma brain metastases. Similar approaches to brain metastases from other primary tumors promise to lead to new and effective therapies. We are beginning to understand the appropriate combination of these novel approaches with our traditional treatment options. As advances in basic and translational science and innovative technologies enter clinical practice, the prognosis of patients with brain metastases will continue to improve.

Challenges and Opportunities in Cancer Drug Resistance

There has been huge progress in the discovery of targeted cancer therapies in recent years. However, even for the most successful and impactful cancer drugs which have been approved, both innate and acquired mechanisms of resistance are commonplace. These emerging mechanisms of resistance have been studied intensively, which has enabled drug discovery scientists to learn how it may be possible to overcome such resistance in subsequent generations of treatments. In some cases, novel drug candidates have been able to supersede previously approved agents; in other cases they have been used sequentially or in combinations with existing treatments. This review summarizes the current field in terms of the challenges and opportunities that cancer resistance presents to drug discovery scientists, with a focus on small molecule therapeutics. As part of this review, common themes and approaches have been identified which have been utilized to successfully target emerging mechanisms of resistance. This includes the increase in target potency and selectivity, alternative chemical scaffolds, change of mechanism of action (covalents, PROTACs), increases in blood-brain barrier permeability (BBBP), and the targeting of allosteric pockets. Finally, wider approaches are covered such as monoclonal antibodies (mAbs), bispecific antibodies, antibody drug conjugates (ADCs), and combination therapies.

Classification of Leptomeningeal Metastases from Solid Organ Malignancies and Clinical Outcomes: Series from a Cancer Research Centre

Leptomeningeal metastases (LMs) are a critical neurological manifestation of solid organ malignancies. Early diagnosis and prompt treatment is necessary to improve outcomes. We classified LM on the basis of cytological or histological and imaging studies. A total of 14 patients of LM from solid organ malignancies diagnosed between July 2016 and December 2018 were included in the series. LM was classified based on cerebrospinal fluid (CSF) cytology and magnetic resonance imaging (MRI) findings. Survival outcomes were noted. LM from carcinoma of breast and lung accounted for most of the cases. Type I LM was seen in 12 patients while 2 accounted for type II LM. Median overall survival (OS) was 40.5 days. Newer-generation tyrosine kinase inhibitor (TKI) therapy seems promising in the treatment of LM. Classification of LM based on cytology/histology and imaging findings allows early diagnosis and treatment. Newer-generation TKIs should be used for the treatment of LM if indicated.

Clinical Perspectives in Brain Metastasis

Brain metastases (BMs) are responsible for decline in neurological function, reduction in overall quality of life, and mortality from recurrent or untreatable lesions. Advances in diagnostics and imaging have led to increased detection of central nervous system (CNS) metastases in patients with progressive cancers. Improved control of extracranial systemic disease, and the limited ability of current therapeutics to cross the blood-brain barrier (BBB) also contribute to the increase in incidence of brain metastases, as tumor cells seek refuge in the brain. Surgery, chemotherapy, and/or radiation (whole-brain radiation therapy and stereotactic radiation surgery [WBRT/SRS]) are a clinically established treatment paradigm for patients with brain metastases. With the advent of genetic and molecular characterization of tumors and their immune microenvironment, clinical trials seek to include targeted drugs into the therapeutic regimen for eligible patients. Several challenges, like treatment of multiple CNS lesions, superior uptake of chemotherapy into the brain, and trials with multidisciplinary approaches, are now being clinically addressed.

Brain metastases in oncogene-driven non-small cell lung cancer

Molecular targeted therapies have significantly improved the treatment outcome of patients with non-small cell lung cancer (NSCLC) harboring driver gene mutations such as receptor (EGFR) or anaplastic lymphoma kinase (ALK). However, the brain is a frequent site of recurrence, and it significantly deteriorates the prognosis of these patients. Treatment strategies include surgical resection, whole-brain radiation therapy, stereotactic radiotherapy, and drug therapy depending on patient condition. First-generation EGFR/ALK tyrosine kinase inhibitors (TKI) demonstrates only limited efficacy for intracranial lesions probably because of low penetration through the blood-brain barrier (BBB). However, newly developed TKIs with improved penetration such as osimertinib for EGFR and alectinib, ceritinib, brigatinib, or lorlatinib for ALK have demonstrated significant intracranial activity that should contribute to improved overall survival. Whole-brain radiation therapy used to be a standard of care that confers alleviation of symptom and modest survival benefit. However, it potentially causes neurological and cognitive deficits as a chronic toxicity. With the prolonged survival owing to newer generation drugs, this toxicity is becoming more relevant. Stereotactic radiotherapy is considered when there are three or fewer lesions, and the lesions are <3 cm as local control of tumor is excellent, and neurotoxicity is less. In this review, we discuss the various aspects of brain metastases occurring in NSCLC patients with driver gene mutations. We also propose a treatment algorithm for these patients.

Brain metastases

An estimated 20% of all patients with cancer will develop brain metastases, with the majority of brain metastases occurring in those with lung, breast and colorectal cancers, melanoma or renal cell carcinoma. Brain metastases are thought to occur via seeding of circulating tumour cells into the brain microvasculature; within this unique microenvironment, tumour growth is promoted and the penetration of systemic medical therapies is limited. Development of brain metastases remains a substantial contributor to overall cancer mortality in patients with advanced-stage cancer because prognosis remains poor despite multimodal treatments and advances in systemic therapies, which include a combination of surgery, radiotherapy, chemotherapy, immunotherapy and targeted therapies. Thus, interest abounds in understanding the mechanisms that drive brain metastases so that they can be targeted with preventive therapeutic strategies and in understanding the molecular characteristics of brain metastases relative to the primary tumour so that they can inform targeted therapy selection. Increased molecular understanding of the disease will also drive continued development of novel immunotherapies and targeted therapies that have higher bioavailability beyond the blood-tumour barrier and drive advances in radiotherapies and minimally invasive surgical techniques. As these discoveries and innovations move from the realm of basic science to preclinical and clinical applications, future outcomes for patients with brain metastases are almost certain to improve.

Incidence of brain metastasis in lung adenocarcinoma at initial diagnosis on the basis of stage and genetic alterations

OBJECTIVE

Patients with lung adenocarcinoma (ADC) are at higher risk of the development of brain metastasis (BM), and genetic alterations are associated with BM.

PATIENTS AND METHODS

A total of 598 patients with lung ADC in our institution between January 2014 and December 2014 were reviewed retrospectively. We evaluated the incidence of BM by stage and genetic alterations.

RESULTS

Of the 598 patients, 97 (16.2%) had BM, which occurred across all stages. The incidence of BM showed a tendency to increase as the stage increased (p < 0.001, trend test). Although patients with EGFR mutations had BM across all stages, those with ALK or K- mutations had BM only in stage III and IV diseases. Regardless of types of mutations, the incidence of BM showed a tendency to increase as the T or N staging increased (p < 0.001 for each of EGFR, ALK, and K-RAS mutations, trend test). Whereas BM incidence showed a tendency to increase as the M staging increased in patients with EGFR-mutant lung ADC (p < 0.001, trend test), there was no linear trend between M staging and ALK (p = 0.469, trend test) or K-RAS mutations (p = 0.066, trend test). After adjusting covariables, EGFR mutations were associated with BM in never-smokers (adjusted OR = 2.07, 95% CI = 1.02-4.34) and K-RAS mutations were risk factors for BM in males (adjusted OR = 3.86, 95% CI = 1.01-14.43).

CONCLUSIONS

BM occurred in approximately 16% of lung ADC patients, including 3% with stage I diseases. Whereas EGFR-mutant lung ADC had BM across all stages, ALK- or K-RAS-mutant lung ADC had BM only in advanced stages. EGFR mutations were risk factors for BM among never-smokers and K-RAS mutations were risk factors among males.