Unrevealing the therapeutic benefits of radiotherapy and consolidation immunotherapy using ctDNA-defined tumor clonality in unresectable locally advanced non-small cell lung cancer

Progression occurs in approximately two-thirds of patients with locally advanced non-small cell lung cancer (LA-NSCLC) receiving chemoradiation and consolidation immunotherapy. Molecular indicators for outcome prediction are under development. A novel metric, the ratio of mean to max variant allele frequency (mmVAF), was derived from 431 pre-treatment tissue biopsies from The Cancer Genome Atlas and evaluated in serial circulating tumor DNA (ctDNA) from 70 LA-NSCLC patients receiving definitive radiotherapy/chemoradiotherapy (RT/CRT) with/without immunotherapy. High mmVAFs in pre-treatment tissue biopsies, indicating clonal predominant tumors (P < 0.01), were associated with inferior overall survival [OS, hazard ratio (HR): 1.48, 95 % confidence interval (CI): 1.11-1.98]. Similar associations of mmVAF with clonality (P < 0.01) and OS (HR: 2.24, 95 % CI: 0.71-7.08) were observed in pre-treatment ctDNA. At 1-month post-RT, ctDNA mmVAF-high patients receiving consolidation immunotherapy exhibited improved progression-free survival (PFS) compared to those who did not (HR: 0.14, 95 % CI: 0.03-0.67). From the baseline to week 4 of RT and/or 1-month post-RT, survival benefits from consolidation immunotherapy were exclusively observed in ctDNA mmVAF-increased patients (PFS, HR: 0.39, 95 % CI: 0.14-1.15), especially in terms of distant metastasis (HR: 0.11, 95 % CI: 0.01-0.95). In summary, our longitudinal data demonstrated the applicability of ctDNA-defined clonality for prognostic stratification and immunotherapy benefit prediction in LA-NSCLC.

Concurrent Tissue and Circulating Tumor DNA Molecular Profiling to Detect Guideline-Based Targeted Mutations in a Multicancer Cohort

Importance

Tissue-based next-generation sequencing (NGS) of solid tumors is the criterion standard for identifying somatic mutations that can be treated with National Comprehensive Cancer Network guideline-recommended targeted therapies. Sequencing of circulating tumor DNA (ctDNA) can also identify tumor-derived mutations, and there is increasing clinical evidence supporting ctDNA testing as a diagnostic tool. The clinical value of concurrent tissue and ctDNA profiling has not been formally assessed in a large, multicancer cohort from heterogeneous clinical settings.

Objective

To evaluate whether patients concurrently tested with both tissue and ctDNA NGS testing have a higher rate of detection of guideline-based targeted mutations compared with tissue testing alone.

Design, Setting, and Participants

This cohort study comprised 3209 patients who underwent sequencing between May 2020, and December 2022, within the deidentified, Tempus multimodal database, consisting of linked molecular and clinical data. Included patients had stage IV disease (non-small cell lung cancer, breast cancer, prostate cancer, or colorectal cancer) with sufficient tissue and blood sample quantities for analysis.

Exposures

Received results from tissue and plasma ctDNA genomic profiling, with biopsies and blood draws occurring within 30 days of one another.

Main Outcomes and Measures

Detection rates of guideline-based variants found uniquely by ctDNA and tissue profiling.

Results

The cohort of 3209 patients (median age at diagnosis of stage IV disease, 65.3 years [2.5%-97.5% range, 43.3-83.3 years]) who underwent concurrent tissue and ctDNA testing included 1693 women (52.8%). Overall, 1448 patients (45.1%) had a guideline-based variant detected. Of these patients, 9.3% (135 of 1448) had variants uniquely detected by ctDNA profiling, and 24.2% (351 of 1448) had variants uniquely detected by solid-tissue testing. Although largely concordant with one another, differences in the identification of actionable variants by either assay varied according to cancer type, gene, variant, and ctDNA burden. Of 352 patients with breast cancer, 20.2% (71 of 352) with actionable variants had unique findings in ctDNA profiling results. Most of these unique, actionable variants (55.0% [55 of 100]) were found in ESR1, resulting in a 24.7% increase (23 of 93) in the identification of patients harboring an ESR1 mutation relative to tissue testing alone.

Conclusions and Relevance

This study suggests that unique actionable biomarkers are detected by both concurrent tissue and ctDNA testing, with higher ctDNA identification among patients with breast cancer. Integration of concurrent NGS testing into the routine management of advanced solid cancers may expand the delivery of molecularly guided therapy and improve patient outcomes.

Circulating tumor DNA (ctDNA) as a biomarker for lung cancer: Early detection, monitoring and therapy prediction

Circulating tumor DNA (ctDNA), i.e., DNA shed from tumor cells into the bloodstream, is emerging as one of the most useful plasma biomarkers in patients with multiple types of cancer, including patients with non-small cell lung cancer (NSCLC). Indeed, NSCLC was the first malignancy in which measurement of ctDNA was approved for clinical use, i.e., mutational testing of EGFR for predicting response to EGFR tyrosine kinase inhibitors in patients with advanced disease. Although historically the gold standard method for EGFR mutational analysis required tumor tissue, the use of ctDNA is more convenient and safer for patients, results in a faster turn-around-time for return of results, provides a more complete representation of genetic alteration in heterogeneous tumors and is less costly to perform. Emerging uses of ctDNA in patients with lung or suspected lung cancer include screening for early disease, surveillance following initial treatment and monitoring response to therapy in metastatic disease. For evaluating therapy response, ctDNA appears to be especially useful in patients receiving targeted therapies against driver oncogenes or immunotherapy. Further work should not only validate these emerging findings but also aim to optimize and standardize ctDNA assays.

Pan-Tumor Analytical Validation and Osimertinib Clinical Validation in EGFR Mutant Non-Small-Cell Lung Cancer, Supporting the First Next-Generation Sequencing Liquid Biopsy in Vitro Diagnostic

Comprehensive genotyping is necessary to identify therapy options for patients with advanced cancer; however, many cancers are not tested, partly because of tissue limitations. Next-generation sequencing (NGS) liquid biopsies overcome some limitations, but clinical validity is not established and adoption is limited. Herein, clinical bridging studies used pretreatment plasma samples and data from FLAURA (NCT02296125; n = 441) and AURA3 (NCT02151981; n = 450) pivotal studies to demonstrate clinical validity of Guardant360 CDx (NGS LBx) to identify patients with advanced EGFR mutant non-small-cell lung cancer who may benefit from osimertinib. The primary end point was progression-free survival (PFS). Patients with EGFR mutation as identified by NGS LBx had significant PFS benefit with first-line osimertinib over standard of care (15.2 versus 9.6 months; hazard ratio, 0.41; P < 0.0001) and with later-line osimertinib over chemotherapy (8.3 versus 4.2 months; hazard ratio, 0.34; P < 0.0001). PFS benefits were similar to the original trial cohorts selected by tissue-based EGFR testing. Analytical validation included accuracy, precision, limit of detection, and specificity. Analytical validity was established for EGFR mutation detection and pan-tumor profiling. Panel-wide limit of detection was 0.1% to 0.5%, with 98% to 100% per-sample specificity. Patients with EGFR mutant non-small-cell lung cancer by NGS LBx had improved PFS with osimertinib, confirming clinical validity. Analytical validity was established for guideline-recommended therapeutic targets across solid tumors. The resulting US Food and Drug Administration approval of NGS LBx demonstrated safety and effectiveness for its intended use and is expected to improve adherence to guideline-recommended targeted therapy use.

Liquid biopsy in non-small cell lung cancer: a meta-analysis of state-of-the-art and future perspectives

Introduction: To date, tissue biopsy represents the gold standard for characterizing non-small-cell lung cancer (NSCLC), however, the complex architecture of the disease has introduced the need for new investigative approaches, such as liquid biopsy. Indeed, DNA analyzed in liquid biopsy is much more representative of tumour heterogeneity. Materials and methods: We performed a meta-analysis of 17 selected papers, to attest to the diagnostic performance of liquid biopsy in identifying EGFR mutations in NSCLC. Results: In the overall studies, we found a sensitivity of 0.59, specificity of 0.96 and diagnostic odds ratio of 24,69. Since we noticed a high heterogeneity among different papers, we also performed the meta-analysis in separate subsets of papers, divided by 1) stage of disease, 2) experimental design and 3) method of mutation detection. Liquid biopsy has the highest sensitivity/specificity in high-stage tumours, and prospective studies are more reliable than retrospective ones in terms of sensitivity and specificity, both NGS and PCR-based techniques can be used to detect tumour DNA in liquid biopsy. Discussion: Overall, liquid biopsy has the potential to help the management of NSCLC, but at present the non-homogeneous literature data, lack of optimal detection methods, together with relatively high costs make its applicability in routine diagnostics still challenging.

A comparative study on ctDNA and tumor DNA mutations in lung cancer and benign cases with a high number of CTCs and CTECs

BACKGROUND

Liquid biopsy provides a non-invasive approach that enables detecting circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs) using blood specimens and theoretically benefits early finding primary tumor or monitoring treatment response as well as tumor recurrence. Despite many studies on these novel biomarkers, their clinical relevance remains controversial. This study aims to investigate the correlation between ctDNA, CTCs, and circulating tumor-derived endothelial cells (CTECs)  while also evaluating whether mutation profiling in ctDNA is consistent with that in tumor tissue from lung cancer patients. These findings will help the evaluation and utilization of these approaches in clinical practice.

METHODS

104 participants (49 with lung cancer and 31 with benign lesions) underwent CTCs and CTECs detection using integrating subtraction enrichment and immunostaining-fluorescence in situ hybridization (SE-iFISH) strategy. The circulating cell-free DNA (cfDNA) concentration was measured and the mutational profiles of ctDNA were examined by Roche AVENIO ctDNA Expanded Kit (targeted total of 77 genes) by next generation sequencing (NGS) in 28 patients (20 with lung cancer and 8 with benign lesions) with highest numbers of CTCs and CTECs. Mutation validation in matched tumor tissue DNA was then performed in 9 patients with ctDNA mutations using a customized xGen pan-solid tumor kit (targeted total of 474 genes) by NGS.

RESULTS

The sensitivity and specificity of total number of CTCs and CTECs for the diagnosis of NSCLC were 67.3% and 77.6% [AUC (95%CI): 0.815 (0.722-0.907)], 83.9% and 77.4% [AUC (95%CI): 0.739 (0.618-0.860)]. The concentration of cfDNA in plasma was statistically correlated with the size of the primary tumor (r = 0.430, P = 0.022) and CYFRA 21-1 (r = 0.411, P = 0.041), but not with the numbers of CTCs and CTECs. In this study, mutations were found to be poorly consistent between ctDNA and tumor DNA (tDNA) in patients, even when numerous CTCs and CTECs were present.

CONCLUSION

Detection of CTCs and CTECs could be the potential adjunct tool for the early finding of lung cancer. The cfDNA levels are associated with the tumor burden, rather than the CTCs or CTECs counts. Moreover, the poorly consistent mutations between ctDNA and tDNA require further exploration.

Upfront liquid next-generation sequencing in treatment-naïve advanced non-small cell lung cancer patients: A prospective randomised study in the Taiwanese health system

BACKGROUND

Next-generation sequencing (NGS) of plasma cell-free DNA identifies driver mutations in advanced non-small cell lung cancer (NSCLC) and may complement routine molecular evaluation. The utility of liquid NGS at the start of tumour workup is undetermined.

METHODS

This is a randomised study of patients with suspected advanced NSCLC. All patients received blood liquid NGS testing at their first clinic visit and underwent standard histological diagnosis and tissue genotyping, encompassing polymerase chain reaction based methods for EGFR mutation, immunohistochemical (IHC) staining for ALK fusion and BRAF V600E mutation, and an IHC screening followed by confirmation using fluorescence in situ hybridization confirmation for ROS1 fusion. They were then randomly assigned to receive NGS results either after tissue genotyping (Group A) or as soon as possible after histological diagnosis of advanced NSCLC (Group B). The study measured time to start of systemic treatment as the primary endpoint and secondary endpoints included biomarker discovery rate, objective response rate (ORR), and progression-free survival (PFS).

RESULTS

This study enroled 180 patients with suspected advanced NSCLC, randomised into two groups. 63 patients in Group A and 59 in Group B with advanced NSCLC were confirmed as advanced NSCLC and analysed. Most had adenocarcinoma (Group A: 77.8%, Group B: 79.7%). The prevalence of EGFR mutations in the two groups was similar (Group A: 57.1%; Group B: 56.6%). Other driver alterations were rare. The median time to treatment was shorter in Group B (20 days) than in Group A (28 days). ORR and PFS did not differ between groups significantly. Liquid NGS had high concordance with tissue testing and identified driver mutations in 42.6% (20/47) of tissue-negative cases.

CONCLUSION

Performing liquid NGS at the initial clinic visit for suspected advanced NSCLC identifies more patients suitable for targeted therapies and shortens time to the start of treatment.

Clinical validity and utility of circulating tumor DNA (ctDNA) testing in advanced non-small cell lung cancer (aNSCLC): a systematic literature review and meta-analysis

Purpose

Circulating tumor DNA (ctDNA) testing has become a promising tool to guide first-line (1L) targeted treatment for advanced non-small cell lung cancer (aNSCLC). This study aims to estimate the clinical validity (CV) and clinical utility (CU) of ctDNA-based next-generation sequencing (NGS) for oncogenic driver mutations to inform 1L treatment decisions in aNSCLC through a systematic literature review and meta-analysis.

Methods

A systematic literature search was conducted in PubMed/MEDLINE and Embase to identify randomized control trials or observational studies reporting CV/CU on ctDNA testing in patients with aNSCLC. Meta-analyses were performed using bivariate random-effects models to estimate pooled sensitivity and specificity. Progression-free/overall survival (PFS/OS) was summarized for CU studies.

Results

Eighteen studies were identified: 17 CV only, 2 CU only, and 1 both. Thirteen studies were included for the meta-analysis on multi-gene detection. The overall sensitivity and specificity for ctDNA detection of any mutation were 0.69 (95% CI, 0.63-0.74) and 0.99 (95% CI, 0.97-1.00) respectively. However, sensitivity varied greatly by driver gene, ranging from 0.29 (95% CI, 0.13-0.53) for ROS 1 to 0.77 (95% CI, 0.63-0.86) for KRAS . Two studies compared PFS with ctDNA versus tissue-based testing followed by 1L targeted therapy found no significant differences. One study reported OS curves on ctDNA-matched and tissue-matched therapies but no hazard ratios were provided.

Conclusion

ctDNA testing demonstrated an overall acceptable diagnostic accuracy in aNSCLC patients, however, sensitivity varied greatly by driver mutation. Further research is needed, especially for uncommon driver mutations, to better understand the CU of ctDNA testing in guiding targeted treatments for aNSCLC.

Impact of Simultaneous Circulating Tumor DNA and Tissue Genotyping in the Workup of Stage IV Lung Adenocarcinoma on Quality of Care in an Academic Community Medical Center

PURPOSE

In patients with metastatic lung adenocarcinoma, evidence-based first-line treatment decisions require analysis of tumors for genomic alterations (GAs). Optimizing the genotyping paradigm may improve the delivery of precision oncology care. Actionable GAs can be identified by analyzing tumor tissue or circulating tumor DNA using liquid biopsy. Consensus guidelines for when to use liquid biopsy have not been established. We evaluated the routine use of liquid biopsy performed simultaneously with tissue testing in patients with newly diagnosed, stage IV lung adenocarcinoma.

METHODS

We performed a retrospective study comparing patients who underwent tissue genotyping alone (standard biopsy group) with patients who had simultaneous liquid and tissue genotyping (combined biopsy group). We examined the time to reach a final diagnosis, the need for repeat biopsies, and diagnostic accuracy.

RESULTS

Forty two patients in the combined biopsy group and 78 in the standard biopsy group met the inclusion criteria. The standard group had a mean time to diagnosis of 33.5 days, compared with 20.6 days in the combined group (P < .001 by two-tailed t-test). In the combined group, 14 patients did not have sufficient tissue for molecular analysis (30%); however, in 11 (79%) of these patients, liquid biopsy identified a GA that eliminated the need for a second tissue biopsy. In patients who completed both tests, each test found actionable GAs missed by the other.

CONCLUSION

Performing liquid biopsy simultaneously with tissue genotyping is feasible in an academic community medical center. Potential advantages of simultaneous liquid and tissue biopsies include shorter time to obtain a definitive molecular diagnosis, reduced need for a repeat biopsy, and improved detection of actionable mutations, although a sequential strategy that saves costs by beginning with a liquid biopsy may be ideal.

A Systematic Review of Mesenchymal Epithelial Transition Factor (MET) and Its Impact in the Development and Treatment of Non-Small-Cell Lung Cancer

Lung cancer represents the leading cause of annual cancer-related deaths worldwide, accounting for 12.9%. The available treatment options for patients who experience disease progression remain limited. Targeted therapeutic approaches are promising but further understanding of the role of genetic alterations in tumorigenesis is imperative. The MET gene has garnered great interest in this regard. The aim of this systematic review was to analyze the findings from multiple studies to provide a comprehensive and unbiased summary of the evidence. A systematic search was conducted in the reputable scientific databases Embase and PubMed, leading to the inclusion of twenty-two articles, following the PRISMA guidelines, elucidating the biological role of MET in lung cancer and targeted therapies. The systematic review was registered in PROSPERO with registration ID: CRD42023437714. MET mutations were detected in 7.6-11.0% of cases while MET gene amplification was observed in 3.9-22.0%. Six studies showed favorable treatment outcomes utilizing MET inhibitors compared to standard treatment or placebo, with increases in PFS and OS ranging from 0.9 to 12.4 and 7.2 to 24.2 months, respectively, and one study reporting an increase in ORR by 17.3%. Furthermore, patients with a higher mutational burden may derive greater benefit from treatment with MET tyrosine kinase inhibitors (TKIs) than those with a lower mutational burden. Conversely, two studies reported no beneficial effect from adjunctive treatment with a MET targeted therapy. Given these findings, there is an urgent need to identify effective therapeutic strategies specifically targeting the MET gene in lung cancer patients.

Matched tissue and liquid biopsies for advanced non-small cell lung cancer patients A potentially indispensable complementary approach

The introduction of liquid biopsies (LB) has brought forth a number of therapeutic opportunities into the domain of thoracic oncology. Many of which have been adopted for care of patients presenting with advanced non-squamous non-small cell lung cancer (aNS-NSCLC). For example, one of the most frequent indications to perform a LB in these patients, at least in Europe, is for patients treated with tyrosine kinase inhibitors (TKIs) targeting EGFR and ALK genomic alterations when the tumor progresses. A tissue biopsy (TB) must then be taken, ideally from a site of a tumor that progresses, in particular if the LB does not permit detection of a mechanism of resistance to TKI. A LB from a patient with aNS-NSCLC is recommended before first-line therapy if no tissue and/or cytological material is accessible or if the extracted nucleic acid is insufficient in amount and/or of poor quality. At present a LB and a TB are rarely performed simultaneously before treatment and/or on tumor progression. This complementary/matched testing approach is still controversial but needs to be better evaluated to determine the true benefit to care of patients. This review provides an update on the complementarity of the LB and TB method for care of patients presenting with aNS-NSCLC.

Clinical utility of a plasma-based comprehensive genomic profiling test in patients with non-small cell lung cancer in Korea

OBJECTIVES

Plasma-based comprehensive circulating cell-free DNA (cfDNA) next generation sequencing (NGS) has shown utility in advanced non-small cell lung cancer (aNSCLC). The aim of this study was to determine the feasibility of cfDNA-based NGS to identify actionable gene alterations in patients with aNSCLC.

PATIENTS AND METHODS

This single-center non-interventional retrospective study evaluated Korean patients with biopsy-confirmed stage III/IV non-squamous aNSCLC. Tissue biopsy samples were collected at baseline, and/or at progression and analysed with Standard of Care (SOC) testing; cfDNA was analyzed by NGS in some patients concurrently.

RESULTS

aNSCLC patients with cfDNA test results (n = 405) were categorized into three groups: treatment naïve (n = 182), progressive aNSCLC after chemotherapy and/or immunotherapy (n = 157), and progressive aNSCLC after tyrosine kinase inhibitors (TKIs) (n = 66). Clinically informative driver mutations were identified for 63.5% of patients which were classified as OncoKB Tiers 1 (44.2%), 2 (3.4%), tier 3 (18.9%), and 4 (33.5%). Concordance between cfDNA NGS and tissue SOC methods for concurrently collected tissue samples (n = 221) with common EGFR mutations or ALK/ROS1 fusions was 96.9%. cfDNA analysis identified tumor genomic alterations in 13 patients that were unidentified with tissue testing, enabling initiation of targeted treatment.

CONCLUSIONS

In clinical practice, results of cfDNA NGS are highly concordant with those of tissue SOC testing in aNSCLC patients. Plasma analysis identified actionable alterations that were missed or not evaluated by tissue testing, enabling the initiation of targeted therapy. Results from this study add to the body of evidence in the support routine use of cfDNA NGS for patients with aNSCLC.

Plasma ctDNA increases tissue NGS-based detection of therapeutically targetable mutations in lung cancers

BACKGROUND

Circulating tumor DNA (ctDNA) has been becoming a novel convenient and noninvasive method for dynamically monitoring landscape of genomic information to guild personalized cancer treatment. In this study we comprehensively evaluated the additional value of plasma ctDNA to routine tissue next generation sequencing (NGS) of therapeutically targetable mutations in lung cancers.

METHODS

The tumor tissues and peripheral blood samples from 423 cases of patients with lung cancer were subjected to NGS of mutations in oncodrivers (EGFR, ERBB2, ALK, ROS1, C-MET, KRAS, BRAF, RET, BRCA1 and BRCA2).

RESULTS

One hundred and ninety-seven cases showed both plasma and tissue positive and 96 showed both negative. The concordance for tissue and blood detection was 69.27% (293/423). 83 (19.62%) cases showed positive by tissue NGS alone and 47 (11.11%) positive by plasma ctDNA alone. The sensitivity of tissue and plasma detection was 85.63%, and 74.62%, respectively. Plasma had lower detection and sensitivity than tissue, but plasma additionally detected some important mutations which were omitted by tissue NGS. Plasma plus tissue increased the detection rate of 66.19% by tissue alone to 77.30% as well as the sensitivity of 85.63-100%. Similar results were also observed when the cases were classified into subpopulations according to different stages (IV vs. III vs. I-II), grades (low vs. middle grade) and metastatic status (metastasis vs. no metastasis).

CONCLUSION

Plasma ctDNA shares a high concordance with tissue NGS, and plasma plus tissue enhances the detection rate and sensitivity by tissue alone, implying that the tissue and plasma detection should be mutually complementary in the clinical application.

Liquid Biopsy Versus Tissue Biopsy to Determine Front Line Therapy in Metastatic Non-Small Cell Lung Cancer (NSCLC)

In the last decade, non-small-cell lung cancer (NSCLC) treatment has improved with the approval of multiple therapies to target specific genetic alterations. Though, next generation sequencing (NGS) has traditionally been conducted from tissue biopsy samples, developing data supports the use of plasma-based circulating tumor DNA (ctDNA), also known as "liquid biopsy," to complement tissue biopsy approaches in guiding front-line therapy. This study is a retrospective analysis of 170 new NSCLC patients treated at 2 cancer centers within a 5-year period who received both tissue and liquid biopsy NGS as standard of care. Based on a treatment schema defined by testing sufficiency, biomarker detection, and turnaround time (TAT), physicians based the majority of their treatments on liquid biopsy results (73.5%) versus tissue biopsy (25.9%). Liquid biopsy NGS returned results on average 26.8 days faster than tissue and reported higher testing success. For guideline-recommended biomarkers, liquid biopsy was 94.8% to 100% concordant with tissue. In comparing testing modalities, a liquid-first approach identified guideline-recommended biomarkers in 76.5% of patients versus 54.9% in a tissue-first approach. There was no significant difference in time-to-treatment, or survival outcomes (overall survival and progression free survival) based on liquid versus tissue biopsy findings. This research demonstrates that liquid biopsy NGS is an effective tool to capture actionable genetic alterations in NSCLC. Due to its high concordance to tissue, faster TAT, and similarity in outcomes and time-to-treatment, liquid biopsy can be used either as a first-line test or concordantly with tissue biopsy to guide treatment decisions in NSCLC.

Can Liquid Biopsy Based on ctDNA/cfDNA Replace Tissue Biopsy for the Precision Treatment of EGFR-Mutated NSCLC?

More and more clinical trials have explored the role of liquid biopsy in the diagnosis and treatment of EGFR-mutated NSCLC. In certain circumstances, liquid biopsy has unique advantages and offers a new way to detect therapeutic targets, analyze drug resistance mechanisms in advanced patients, and monitor MRD in patients with operable NSCLC. Although its potential cannot be ignored, more evidence is needed to support the transition from the research stage to clinical application. We reviewed the latest progress in research on the efficacy and resistance mechanisms of targeted therapy for advanced NSCLC patients with plasma ctDNA EGFR mutation and the evaluation of MRD based on ctDNA detection in perioperative and follow-up monitoring.

Next-Generation Sequencing for Advanced Breast Cancer: What the Way to Go?

The rapid implementation of precision medicine tools in diagnosing and treating breast cancer (BC) has widened the potential therapeutic options for patients. The applications of gene sequencing, including next-generation gene sequencing (NGS), have led to numerous questions on how to validate, implement, interpret, prioritize and operationalize precision medicine tools to deliver meaningful and impactful interventions. Limited benefit has been portended with earlier experiences of NGS-driven treatment, in BC. However, the development and use of frameworks of clinical actionability of genomic alterations, for example, detected with NGS, has resulted in better patient selection, and potentially higher therapeutic value. The European Society for Medical Oncology Scale for Clinical Actionability of molecular Targets (ESCAT) is a framework that includes five tiers of clinical actionability, with tier 1 reserved for approved drugs with demonstrated benefits for targetable genomic alterations. The re-analysis of clinical studies by grouping the genomic alterations and matched drugs with ESCAT, in high vs lower tiers has demonstrated a significant benefit portended by high tiers alterations, with the availability of efficacious treatments. As a result, frameworks for actionability, like ESCAT, should be fundamental in developing and implementing NGS-driven, and broadly, precision medicine research and treatments.

Liquid Biopsy and the Translational Bridge from the TIME to the Clinic

Research and advancing understanding of the tumor immune microenvironment (TIME) is vital to optimize and direct more effective cancer immune therapy. Pre-clinical bench research is vital to better understand the genomic interplay of the TIME and immune therapy responsiveness. However, a vital key to effective translational cancer research is having a bridge of translation to bring that understanding from the bench to the bedside. Without that bridge, research into the TIME will lack an efficient and effective translation into the clinic and cancer treatment decision making. As a clinical oncologist, the purpose of this commentary is to emphasize the importance of researching and improving clinical utility of the bridge, as well as the TIME research itself.

[Research Progress of Circulating Tumor DNA in Non-small Cell Lung Cancer]

With the concept of "Precision Medicine" in malignant tumors popularized, many substances carrying valuable clinical information have emerged in the process of exploring the occurrence and development of tumors from a microscopic perspective. Circulating tumor DNA (ctDNA) is one of them. In various clinical stages of cancer, ctDNA exhibits rich diagnostic values including demonstrating the efficacy of treatment, predicting prognosis, and monitoring disease recurrence. This article mainly describes the application and research progress of ctDNA in different stages of clinical diagnosis and treatment of non-small cell lung cancer .
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Real-World Clinical Outcomes after Genomic Profiling of Circulating Tumor DNA in Patients with Previously Treated Advanced Non-Small Cell Lung Cancer

Comprehensive genomic profiling for advanced non-small cell lung cancer (NSCLC) can identify patients for molecularly targeted therapies that improve clinical outcomes. We analyzed data from 3084 patients (median age 65 years, 72.9% with adenocarcinoma) with advanced NSCLC registered in a real-world healthcare claims database (GuardantINFORMTM, Guardant Health) who underwent next-generation sequencing (NGS)-based circulating tumor DNA (ctDNA) testing (Guardant360®, Guardant Health) after first-line therapy (28.0% with agents targeted against genomic alterations). ctDNA was detected in 2771 samples (89.9%), of which 41.9% harbored actionable alterations, most commonly EGFR (epidermal growth factor receptor) mutations (29.7%). Actionable alterations were detected in 26.7% of patients (534/2001) previously treated with non-targeted agents. Emerging potentially targetable mutations were found in 40.1% (309/770) of patients previously treated with targeted therapies. Among patients with qualifying alterations detected by ctDNA testing, the time to treatment discontinuation (median 8.8 vs. 4.2 months; hazard ratio 1.97, p < 0.001) and overall survival (median 36.1 vs. 16.6 months; hazard ratio 2.08, p < 0.001) were longer for those who received matched second-line therapy versus unmatched second-line therapy. In real-world practice, results of a blood-based NGS assay prior to second-line treatment inform therapeutic decisions that can improve clinical outcomes for patients with advanced NSCLC.

Will We Unlock the Benefit of Metformin for Patients with Lung Cancer? Lessons from Current Evidence and New Hypotheses

Metformin has been under basic and clinical study as an oncological repurposing pharmacological agent for several years, stemming from observational studies which consistently evidenced that subjects who were treated with metformin had a reduced risk for development of cancer throughout their lives, as well as improved survival outcomes when diagnosed with neoplastic diseases. As a result, several basic science studies have attempted to dissect the relationship between metformin’s metabolic mechanism of action and antineoplastic cellular signaling pathways. Evidence in this regard was compelling enough that a myriad of randomized clinical trials was planned and conducted in order to establish the effect of metformin treatment for patients with diverse neoplasms, including lung cancer. As with most novel antineoplastic agents, early results from these studies have been mostly discouraging, though a recent analysis that incorporated body mass index may provide significant information regarding which patient subgroups might derive the most benefit from the addition of metformin to their anticancer treatment. Much in line with the current pipeline for anticancer agents, it appears that the benefit of metformin may be circumscribed to a specific patient subgroup. If so, addition of metformin to antineoplastic agents could prove one of the most cost-effective interventions proposed in the context of precision oncology. Currently published reviews mostly rely on a widely questioned mechanism of action by metformin, which fails to consider the differential effects of the drug in lean vs. obese subjects. In this review, we analyze the pre-clinical and clinical information available to date regarding the use of metformin in various subtypes of lung cancer and, further, we present evidence as to the differential metabolic effects of metformin in lean and obese subjects where, paradoxically, the obese subjects have reported more benefit with the addition of metformin treatment. The novel mechanisms of action described for this biguanide may explain the different results observed in clinical trials published in the last decade. Lastly, we present novel hypothesis regarding potential biomarkers to identify who might reap benefit from this intervention, including the role of prolyl hydroxylase domain 3 (PHD3) expression to modify metabolic phenotypes in malignant diseases.

A clinician’s handbook for using ctDNA throughout the patient journey

Background

The promise of precision cancer medicine presently centers around the genomic sequence of a patient’s tumor being translated into timely, actionable information to inform clinical care. The analysis of cell-free DNA from liquid biopsy, which contains circulating tumor DNA (ctDNA) in patients with cancer, has proven to be amenable to various settings in oncology. However, open questions surrounding the clinical validity and utility of plasma-based analyses have hindered widespread clinical adoption.

Main body

Owing to the rapid evolution of the field, studies supporting the use of ctDNA as a biomarker throughout a patient’s journey with cancer have accumulated in the last few years, warranting a review of the latest status for clinicians who may employ ctDNA in their precision oncology programs. In this work, we take a step back from the intricate coverage of detection approaches described extensively elsewhere and cover basic concepts around the practical implementation of next generation sequencing (NGS)-guided liquid biopsy. We compare relevant targeted and untargeted approaches to plasma DNA analysis, describe the latest evidence for clinical validity and utility, and highlight the value of genome-wide ctDNA analysis, particularly as it relates to early detection strategies and discovery applications harnessing the non-coding genome.

Conclusions

The maturation of liquid biopsy for clinical application will require interdisciplinary efforts to address current challenges. However, patients and clinicians alike may greatly benefit in the future from its incorporation into routine oncology care.

Use of Circulating Tumour DNA (ctDNA) for Measurement of Therapy Predictive Biomarkers in Patients with Cancer

Biomarkers that predict likely response or resistance to specific therapies are critical in personalising treatment for cancer patients. Such biomarkers are now available for an increasing number of anti-cancer therapies, especially targeted therapy and immunotherapy. The gold-standard method for determining predictive biomarkers requires tumour tissue. Obtaining tissue, however, is not always possible and even if possible, the amount or quality of tissue obtained may be inadequate for biomarker analysis. Tumour DNA, however, can be released into the bloodstream, giving rise to what is referred to as circulating tumour DNA (ctDNA). In contrast to tissue, blood can be obtained from effectively all patients in a minimally invasive and safe manner. Other advantages of blood over tissue for biomarker testing include a shorter turn-around time and an ability to perform serial measurements. Furthermore, blood should provide a more complete profile of mutations present in heterogeneous tumours than a single-needle tissue biopsy. A limitation of blood vis-à-vis tissue, however, is lower sensitivity and, thus, the possibility of missing an actionable mutation. Despite this limitation, blood-based predictive biomarkers, such as mutant EGFR for predicting response to EGFR tyrosine kinase inhibitors in advanced non-small-cell lung cancer and mutant PIK3CA for predicting response to alpelisib in combination with fulvestrant in advanced breast cancer, may be used when tissue is unavailable. Although tissue remains the gold standard for detecting predictive biomarkers, it is likely that several further blood-based assays will soon be validated and used when tissue is unavailable or unsuitable for analysis.

Clinical utility of liquid biopsy-based companion diagnostics in the non-small-cell lung cancer treatment

Recently, technological advances in the detection and biological characterization of circulating tumor DNA (ctDNA) have enabled the implementation of liquid biopsy testing into clinical practice. Methods for analysis of liquid biopsies have rapidly evolved over the past few years and have continued to advance, thus providing details about tumor biological characteristics such as tumor progression, metastasis, tumor heterogeneity, genomic mutation profile, clonal evolution, etc. In tandem with technological advances, the implementation of liquid biopsy in routine clinical settings has proceeded. In 2016, the Food and Drug Administration (FDA) approved the first ctDNA liquid biopsy test to detect epidermal growth factor receptor (EGFR) gene mutations in patients with non-small-cell lung cancer (NSCLC) as a companion diagnostic for molecular targeted drug of EGFR-tyrosine kinase inhibitor (TKI, EGFR-TKI). More recently, multigene panel assays of liquid biopsy have been approved as companion diagnostics and have been used in routine clinical settings. The estimation of blood tumor mutation burden (bTMB) to predict the efficacy of immune checkpoint inhibitor (ICI) treatment can be one of the promising approaches to liquid biopsy. The next stage of implementation of liquid biopsy for routine clinical settings is for monitoring of ctDNA after surgical treatment to predict prognosis and to detect disease relapse earlier than conventional imaging diagnosis. Its clinical utility is under assessment in several clinical trials. This review introduces recent advances in liquid biopsy methodology, the development of biomarkers, and its clinical utility in the treatment of NSCLC patients.

Clinical Outcomes for Plasma-Based Comprehensive Genomic Profiling Versus Standard-of-Care Tissue Testing in Advanced Non-Small Cell Lung Cancer

BACKGROUND

Somatic genomic testing is recommended by numerous expert guidelines to inform targeted therapy treatment for patients with advanced nonsquamous non-small cell lung cancer (aNSCLC). The NILE study was a prospective observational study that demonstrated noninferiority of cell-free circulating tumor DNA (cfDNA)-based tumor genotyping compared to tissue-based genotyping to find targetable genomic alterations in patients with newly diagnosed nonsquamous aNSCLC. As the cohort has matured, clinical outcomes data can now be analyzed.

METHODS

This prospective, multicenter North American study enrolled patients with previously untreated nonsquamous aNSCLC who had standard of care (SOC) tissue genotyping performed and concurrent comprehensive cfDNA analysis (Guardant360). Patients with targetable genomic alterations, as defined by NCCN guidelines, who were treated with physician's choice of therapy had objective response rates, disease control rate, and time to treatment collected and compared to published outcomes.

RESULTS

Among 282 patients, 89 (31.6%) had an actionable biomarker, as defined by NCCN, detected by tissue (21.3%) and/or cfDNA (27.3%) analysis. Sixty-one (68.5%) of these were treated with an FDA-approved targeted therapy guided by somatic genotyping results (EGFR, ALK, ROS1). Thirty-three patients were eligible for clinical response evaluation and demonstrated an objective response rate of 58% and disease control rate of 94%. Twenty-five (76%) and 17 (52%) achieved a durable response > 6 months and 12 months, respectively. The time to treatment (TtT) was significantly faster for cfDNA-informed biomarker detection as compared to tissue genotyping (18 vs. 31 days, respectively; P = .0008).

CONCLUSIONS

cfDNA detects guideline-recommended biomarkers at a rate similar to tissue genotyping, and therapeutic outcomes based on plasma-based comprehensive genomic profiling are comparable to published targeted therapy outcomes with tissue profiling, even in community-based centers.

Mutated circulating tumor DNA as a liquid biopsy in lung cancer detection and treatment

Over the past decade, substantial developments have been made in the detection of circulating tumor DNA (ctDNA)-cell-free DNA (cfDNA) fragments released into the circulation from tumor cells and displaying the genetic alterations of those cells. As such, ctDNA detected in liquid biopsies serves as a powerful tool for cancer patient stratification, therapy guidance, detection of resistance, and relapse monitoring. In this Review, we describe lung cancer diagnosis and monitoring strategies using ctDNA detection technologies and compile recent evidence regarding lung cancer-related mutation detection in liquid biopsy. We focus not only on epidermal growth factor receptor (EGFR) alterations, but also on significant co-mutations that shed more light on novel ctDNA-based liquid biopsy applications. Finally, we discuss future perspectives of early-cancer detection and clonal hematopoiesis filtering strategies, with possible inclusion of microbiome-driven liquid biopsy.

Targeted Therapy in Advanced and Metastatic Non-Small Cell Lung Cancer. An Update on Treatment of the Most Important Actionable Oncogenic Driver Alterations

Due to groundbreaking developments and continuous progress, the treatment of advanced and metastatic non-small cell lung cancer (NSCLC) has become an exciting, but increasingly challenging task. This applies, in particular, to the subgroup of NSCLC with oncogenic driver alterations. While the treatment of epidermal growth factor receptor (EGFR)-mutated and anaplastic lymphoma kinase (ALK)-rearranged NSCLC with various tyrosine kinase inhibitors (TKIs) is well-established, new targets have been identified in the last few years and new TKIs introduced in clinical practice. Even for KRAS mutations, considered for a long time as an "un-targetable" alteration, promising new drugs are emerging. The detection and in-depth molecular analysis of resistance mechanisms has further fueled the development of new therapeutic strategies. The objective of this review is to give a comprehensive overview on the current landscape of targetable oncogenic alterations in NSCLC.