KRAS mutations testing in non-small cell lung cancer: the role of Liquid biopsy in the basal setting

Liquid Biopsy in Solid Tumours: An Overview

The advent of personalised and precision medicine has radically modified the management and the clinical outcome of cancer patients. However, the expanding number of predictive, prognostic, and diagnostic biomarkers has raised the need for simple, noninvasive, quicker, but equally efficient tests for molecular profiling. In this complex scenario, the adoption of liquid biopsy, particularly circulating tumour DNA (ctDNA), has been a real godsend for many cancer patients who would otherwise have been denied the benefits of targeted treatments. Undeniably, ctDNA analysis has several advantages over conventional tissue-based analysis. One advantage is that it can guide treatment decision making, especially when tissue samples are scarce or totally unavailable. Indeed, a simple blood test can inform clinicians on patients' response or resistance to targeted therapies, help them monitor minimal residual disease (MRD) after surgical resections, and facilitate them with early cancer detection and interception. Finally, an equally important advantage is that ctDNA analysis can help decipher temporal and spatial tumour heterogeneity, a mechanism highly responsible for therapeutic resistance. In this review, we gathered and analysed current evidence on the clinical usefulness of ctDNA analysis in solid tumours.

Thoracic metabolic tumor volume predicts survival in advanced lung adenocarcinoma: a PET/computed tomography-based cohort study

INTRODUCTION

Advanced-stage lung adenocarcinoma is associated with poor survival, highlighting the need for improved prognostic tools. PET/computed tomography (CT) metrics and mutation profiling may enhance risk stratification when integrated with clinical parameters.

METHODS

This retrospective cohort study included 109 advanced-stage lung adenocarcinoma between 2018 and 2023. PET/CT metrics - standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) - were assessed for primary tumors and thoracic regions. ECOG performance status and mutation profiles were also recorded. Cox regression analysis was performed to identify independent predictors of overall survival (OS).

RESULTS

In univariate analysis, all PET/CT parameters were significantly associated with OS. In multivariate analysis, thoracic MTV emerged as the strongest independent prognostic factor (HR = 2.85, 95% CI: 1.69-4.81, P < 0.001), followed by ECOG ≥2 (HR = 2.31, 95% CI: 1.18-3.72, P = 0.004). Although KRAS mutations were associated with poorer OS in univariate analysis, they did not retain significance in the multivariate model.

CONCLUSION

Our findings emphasize the prognostic value of thoracic MTV as a robust, independent biomarker for advanced-stage lung adenocarcinoma. Integrating PET/CT metrics with clinical and molecular data may improve staging accuracy and inform treatment decisions, particularly in settings where mutational status alone is insufficient.

Efficacy of liquid biopsy for genetic mutations determination in non-small cell lung cancer: a systematic review on literatures

BACKGROUND

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide and is often diagnosed at advanced stages, limiting treatment options. This systematic review aims to evaluate the efficacy of liquid biopsy in detecting genetic mutations in NSCLC, focusing on its sensitivity, specificity, clinical utility, and potential to guide personalized treatment strategies.

METHODS

A systematic search was conducted in PubMed, Scopus, Embase, Web of Science, and Cochrane Library to identify relevant studies published between 1990 and September 2024. Eligible studies included comparative analyses of liquid biopsy techniques for NSCLC diagnosis, prognosis, progression, or treatment response. This review adheres to the PRISMA 2020 guidelines and assesses study quality using the QUADAS framework.

RESULTS

A total of 30 studies were included. Digital droplet PCR (ddPCR) demonstrated the highest sensitivity, detecting low-frequency mutations such as EGFR T790M at levels as low as 0.01%. Next-generation sequencing (NGS) provided comprehensive mutational profiling, revealing tumor heterogeneity and co-existing mutations but required high-quality plasma samples. The cobas EGFR Mutation Test, while less sensitive than ddPCR, remains widely used due to its clinical accessibility. Emerging methods, including extracellular vesicle analysis, show promise but require further validation. Additionally, liquid biopsy effectively identified non-EGFR mutations, such as KRAS, ALK, and MET amplifications, expanding its clinical applicability.

CONCLUSION

Liquid biopsy is a transformative tool in NSCLC management, offering a minimally invasive approach for mutation detection, disease monitoring, and treatment guidance. Future research should focus on multicenter trials and emerging technologies to enhance clinical integration and broaden applicability across different cancer types.

Early monitoring of plasma KRAS G12C with digital PCR predicts antitumor response to immunotherapy or sotorasib in advanced NSCLC: A brief report

Background

The frontline management of non-oncogene addicted non-small cell lung cancer (NSCLC) involves immune-checkpoint inhibitors (ICI) alone or combined with chemotherapy (CT-ICI). The dynamic landscape of KRAS-positive NSCLC presents a spectrum of treatment options, including ICIs, targeted therapy and combination strategies currently under investigation.

Methods

We conducted a prospective project to detect circulating tumor DNA (ctDNA) in patients with KRAS G12C, advanced NSCLC. We included patients undergoing upfront ICIs or subsequent line sotorasib. We planned three-time points: baseline (T0), after 3 months of treatment (T1) and at disease progression (T2).

Results

24 consecutive patients have been included. The most frequent baseline characteristics were: nonsquamous histology (95.8%), male gender (62.5%), ECOG PS 0-1 (79.2%), <3 metastatic sites (13/24, 54.2%). 18 patients (75%) received ICI-based strategies and 6 patients (25%) sotorasib. Patients with liver metastases (p ​= ​0.01) and those with >3 metastatic sites (p ​= ​0.002) exhibited significantly elevated ctDNA. Median overall survival (OS) was 7.5 months, progression-free survival (PFS) was 4.0 months and the objective response rate (ORR) was 33.3%. Higher AF correlated with an increased risk of death (HR 1.04, p ​= ​0.03), though not progression. The mOS was 7.5 months (95% CI, 1.91-NR) in high-AF group and 11.3 months (95% CI, 6.6-NR) in low-AF group (p ​= ​0.38). Notably, a reduction in plasma DNA levels was significantly associated with objective response (p ​= ​0.01). Two patients received a T2 dosage showing increased ctDNA levels after a previous reduction associated with response.

Conclusion

Early monitoring with ctDNA may offer potential benefits in the evolving scenario of KRAS G12C NSCLC treatment.

KRAS mutations detection methodology: from RFLP to CRISPR/Cas based methods

In personalized cancer medicine, the identification of KRAS mutations is essential for making treatment decisions and improving patient outcomes. This work presents a comprehensive review of the current approaches for detection of KRAS mutations in different cancers. We highlight the value of fast and reliable KRAS mutations discovery and the effectiveness of molecular testing for selecting individuals who might benefit from targeted therapy. We provide an overview of various methods and tools available for detecting KRAS mutations, such as digital droplet PCR, next-generation sequencing (NGS), and polymerase chain reaction (PCR). We also address the difficulties and limitations in the identification of KRAS mutations, namely tumor heterogeneity and the emergence of resistance mechanisms. This article aims to guide clinicians in KRAS mutation identification.

An updated overview of K-RAS G12C inhibitors in advanced stage non-small cell lung cancer

The discovery of KRAS mutations, particularly the KRASG12C variant, has been a milestone in understanding the molecular underpinnings of non-small cell lung cancer (NSCLC). These mutations are associated with aggressive tumor behavior and resistance to conventional therapies, highlighting the urgent need for targeted interventions. In this comprehensive review, we analyze the advancements in KRAS G12C inhibitors for the treatment of non-small cell lung cancer. Literature search is made from PubMed, Medline ASCO and ESMO Annual Meetings abstracts by using the following search keywords: "sotorasib", "adagrasib", "divarasib" and "KRAS G12C inhibitors." The last search was on 5 June 2024. This review highlights the importance of pharmacokinetics, pharmacodynamics and potential adverse effects for treating individual patients and ensuring the best outcomes. Additionally, the review discusses research identifying biomarkers that can predict therapy responses and mentions the combination strategies to overcome resistance. Results of the studies and ongoing clinical trials are also briefly summarized in this review. KRASG12C inhibitors sotorasib, adagrasib and the newer divarasib, has revolutionized treating patients harboring this mutation. Ongoing studies and future clinical trials will refine our understandings with the ultimate goal of improving survival and quality of life for patients with this challenging disease.

Detection and Characterization of Methylated Circulating Tumor DNA in Gastric Cancer

Gastric cancer is the fifth most common disease in the world and the fourth most common cause of death. It is diagnosed through esophagogastroduodenoscopy with biopsy; however, there are limitations in finding lesions in the early stages. Recently, research has been actively conducted to use liquid biopsy to diagnose various cancers, including gastric cancer. Various substances derived from cancer are reflected in the blood. By analyzing these substances, it was expected that not only the presence or absence of cancer but also the type of cancer can be diagnosed. However, the amount of these substances is extremely small, and even these have various variables depending on the characteristics of the individual or the characteristics of the cancer. To overcome these, we collected methylated DNA fragments using MeDIP and compared them with normal plasma to characterize gastric cancer tissue or patients' plasma. We attempted to diagnose gastric cancer using the characteristics of cancer reflected in the blood through the cancer tissue and patients' plasma. As a result, we confirmed that the consistency of common methylated fragments between tissue and plasma was approximately 41.2% and we found the possibility of diagnosing and characterizing cancer using the characteristics of the fragments through SFR and 5'end-motif analysis.

Targeting KRASG12C in Non-Small-Cell Lung Cancer: Current Standards and Developments

Among the most common molecular alterations detected in non-small-cell lung cancer (NSCLC) are mutations in Kristen Rat Sarcoma viral oncogene homolog (KRAS). KRAS mutant NSCLC is a heterogenous group of diseases, different from other oncogene-driven tumors in terms of biology and response to therapies. Despite efforts to develop drugs aimed at inhibiting KRAS or its signaling pathways, KRAS had remained undruggable for decades. The discovery of a small pocket in the binding switch II region of KRASG12C has revolutionized the treatment of KRASG12C-mutated NSCLC patients. Sotorasib and adagrasib, direct KRASG12C inhibitors, have been approved by the US Food and Drug Administration (FDA) and other regulatory agencies for patients with previously treated KRASG12C-mutated NSCLC, and these advances have become practice changing. However, first-line treatment in KRASG12C-mutated NSCLC does not differ from NSCLC without actionable driver genomic alterations. Treatment with KRASG12C inhibitors is not curative and patients develop progressive disease, so understanding associated mechanisms of drug resistance is key. New KRASG12C inhibitors and several combination therapy strategies, including with immune checkpoint inhibitors, are being studied in clinical trials. The aim of this review is to explore the clinical impact of KRAS, and outline different treatment approaches, focusing on the novel treatment of KRASG12C-mutated NSCLC.

Roles of Tumor-Educated Platelets (TEPs) in the biology of Non-Small Cell Lung Cancer (NSCLC): A systematic review. "Re-discovering the neglected biosources of the liquid biopsy family"

Due to their interactions with the neoplasm, platelets undergo various proteomic and transcriptomic modifications, resulting in the development of what is known as the "Tumor-Educated Platelets (TEPs) phenotype". Consequently, in addition to their suitability for Liquid Biopsy (LB) applications, they play a pivotal role in the malignancy by communicating with Circulating Tumor Cells (CTCs), Tumor Microenvironment (TME), and the tumor itself through multiple mechanisms and at multiple levels, ultimately promoting the metastasis of cancer. Therefore, this Systematic Review of MEDLINE and the Cochrane Library present in-depth insights into these phenomena, with the aim of enhancing the understanding of the complex interplay between TEPs and Non-Small Cell Lung Cancer (NSCLC). This endeavor serves to provide context and drive medical research efforts, which are increasingly focused on developing novel diagnostic and therapeutic technologies that leverage the specific binding of these platelets to the disease.

Clinical characteristics, outcomes and prognostic factors in KRAS mutant lung cancers: experience from a tertiary care cancer center in India

Objectives

Kirsten rat sarcoma viral oncogene homologue (KRAS) mutations in lung cancers, long considered untargetable, have had a recent rise in interest due to promising data of agents targeting KRAS p.G12C. As Indian data are scarce, we sought to identify baseline clinical characteristics, prognostic factors and outcomes of lung cancer patients with KRAS mutations at our hospital.

Methods

Patients with KRAS mutant lung cancers treated at our institute from 2016 to 2022 were analysed.

Results

133 patients with KRAS mutant lung cancers were identified. Median age was 57 (interquartile range 28-78) years, and 58 (43.6%) were smokers. 17 (12.7%) had brain metastases. The commonest variant was p.G12C, seen in 53 (39.8%) patients. Six (4.5%) had programmed death ligand 1 (PDL-1) expression >50% by Ventana SP263 PDL-1 assay, and 13 (9.7%) had epidermal growth factor mutation. Of 92 patients with available treatment details, the majority received intravenous chemotherapy, nine (9.8%) received tyrosine kinase inhibitors and four (4.4%) received immunotherapy (pembrolizumab). Median progression-free survival (PFS) with first-line therapy was 6 (95% confidence interval (CI) 2.8-9.2) months and median overall survival (OS) was 12 (CI 9.2-14.8) months. The incidence of brain metastases was higher in patients with G12C mutations (p = 0.025). Brain metastases (HR: 3.57, p < 0.001), Eastern Cooperative Oncology Group performance status (PS) ≥ 2 (HR: 2.13, p = 0.002) and G12C mutation (HR: 1.84, p = 0.011) were associated with inferior PFS, while brain metastases (HR: 4.6, p < 0.001), PS ≥ 2 (HR: 2.33, p = 0.001) and G12C mutation (HR: 1.93, p = 0.01) were associated with inferior OS.

Conclusion

This is the largest dataset of KRAS mutant lung cancers from India. Brain metastases were higher in patients with G12C mutations and associated with poorer PFS and OS. G12C mutation and PS ≥ 2 were also associated with inferior PFS and OS. Experience with targeted therapy for KRAS mutations remains an area of future exploration due to the unavailability of these agents in India.

Abnormalities in the KRAS Gene and Treatment Options for NSCLC Patients with the G12C Mutation in This Gene-A Literature Review and Single-Center Experience

Mutations in the KRAS gene are among the most common mutations observed in cancer cells, but they have only recently become an achievable goal for targeted therapies. Two KRAS inhibitors, sotorasib and adagrasib, have recently been approved for the treatment of patients with advanced non-small cell lung cancer with the KRAS G12C mutation, while studies on their efficacy are still ongoing. In this work, we comprehensively analyzed RAS gene mutations' molecular background, mutation testing, KRAS inhibitors' effectiveness with an emphasis on non-small cell lung cancer, the impact of KRAS mutations on immunotherapy outcomes, and drug resistance problems. We also summarized ongoing trials and analyzed emerging perspectives on targeting KRAS in cancer patients.

Mutation profile in liquid biopsy tested by next generation sequencing in Mexican patients with non-small cell lung carcinoma and its impact on survival

Background

Lung cancer represents a significant global health concern, often diagnosed in its advanced stages. The advent of massive DNA sequencing has revolutionized the landscape of cancer treatment by enabling the identification of target mutations and the development of tailored therapeutic approaches. Unfortunately, access to DNA sequencing technology remains limited in many developing countries. In this context, we emphasize the critical importance of integrating this advanced technology into healthcare systems in developing nations to improve treatment outcomes.

Methods

We conducted an analysis of electronic clinical records of patients with confirmed advanced non-small cell lung cancer (NSCLC) and a verified negative status for the epidermal growth factor receptor (EGFR) mutation. These patients underwent next-generation sequencing (NGS) for molecular analysis. We performed descriptive statistical analyses for each variable and conducted both univariate and multivariate statistical analyses to assess their impact on progression-free survival (PFS) and overall survival (OS). Additionally, we classified genetic mutations as actionable or non-actionable based on the European Society for Medical Oncology Scale of Clinical Actionability of Molecular Targets (ESCAT) guidelines.

Results

Our study included a total of 127 patients, revealing the presence of twenty-one distinct mutations. The most prevalent mutations were EGFR (18.9%) and Kirsten rat sarcoma viral oncogene homolog (KRAS) (15.7%). Notably, anaplastic lymphoma kinase (ALK) [hazard ratio (HR): 0.258, P<0.001], tumor mutation burden (TMB) (HR: 2.073, P=0.042) and brain magnetic resonance imaging (MRI) (HR: 0.470, P=0.032) demonstrated statistical significance in both the univariate and multivariate analyses with respect to PFS. In terms of OS, ALK (HR: 0.285, P<0.001) and EGFR (HR: 0.482, P=0.024) exhibited statistical significance in both analyses. Applying the ESCAT classification system, we identified actionable genomic variations (ESCAT level-1), including EGFR, ALK, breast cancer (BRAF) gene, c-ros oncogene 1 (ROS1), and rearranged during transfection (RET) gene, in 32.3% of the patients.

Conclusions

Our findings from massive DNA sequencing underscore that 32.3% of patients who test negative for the EGFR mutation possess other targetable mutations, enabling them to receive personalized, targeted therapies at an earlier stage of their disease. Implementing massive DNA sequencing in developing countries is crucial to enhance survival rates among NSCLC patients and guide more effective treatment strategies.

Tweezer PCR: A Highly Specific Method for Accurate Identification of Low-Abundance Mutations

Somatic mutation is a valuable biomarker for tracking tumor progression and migration due to its distinctive feature in various tumors and its wide distribution throughout body fluids. However, accurately detecting somatic mutations from the abundant DNA of noncancerous origins remains a practical challenge in the clinic. Herein, we developed an ultraspecific method, called tweezer PCR, for detecting low-abundance mutations inspired by the design of DNA origami. The high specificity of tweezer PCR relies on a tweezer-shaped primer containing six basic functional units: a primer, a hairpin, a linker, a blocker, a spacer, and a toehold. After optimizing the structure of the tweezer-shaped primer and enhancing its specificity by adding additional Mg2+ and Na+, tweezer PCR distinguished as low as 20 copies of mutations from 2 million copies of wild-type templates per test. By testing synthesized plasmids and plasma samples gathered from nonsmall-cell lung cancer patients, tweezer PCR showed higher specificity and robustness for detecting low-copy-number mutations in contrast with digital droplet PCR. Additionally, the need for conventional instruments makes tweezer PCR a practically accessible method for testing low-abundance mutations. Because of its numerous advantages, we believe that tweezer PCR offers a precise, robust, and pragmatic tool for cancer screening, prognosis, and genotyping in the clinic.

Liquid biopsy for lung cancer: A cross section on the diagnostic routine experience of a referral Italian institution

Background

Lung cancer is the leading cause of cancer death worldwide. Over the last decade, molecular testing of a growing number of predictive biomarkers has become mandatory in the management of NSCLC patients. However, a major obstacle in routine clinical practice is the scant quantity of available tissue specimens obtainable from advanced stage of NSCLC patients. Thus, liquid biopsy, mostly involving blood sampling, has now been integrated in routine diagnostic practice. However, although liquid biopsies constitute a versatile, compliant, and dynamic source of nucleic acids, many of the current testing approaches pose few technical challenges. Here, to validate the feasibility of implementing NGS-based liquid biopsy approaches in routine diagnostic practice, we overviewed the NGS molecular data generated by our in-house narrow gene panel on plasma samples from real-world NSCLC patients.

Methods

Our Institution received testing request on liquid biopsy samples from peripheral institutions not equipped to internally analyze liquid biopsy samples. Molecular data from NSCLC patients following oncological requested for clinically approved plasma-based biomarkers evaluated in a diagnostic routine setting from January 2020 to September 2022 were retrieved from our institutional archive. A customized NGS panel integrated with an optimized bioinformatic pipeline was adopted.

Results

Overall, a total of n = 185 cases were retrieved. Of note, 103 (55.7 %) and 82 (44.3 %) patients were analyzed at basal setting and after resistance to first line TKI administration, respectively. Moreover, 31 out of 185 (16.7 %) cases reveled EGFR clinically relevant alterations. In particular, 6 out of 31 (19.3 %) and 25 out 31 (80.7 %) EGFR mutated patients were tested in basal setting and after first or second line TKIs progression. In addition, exon 20 p.T790 M mutation was also detected in 12 out of 25 (48.0 %) EGFR concomitant mutated cases. Moreover, KRAS hot spot mutations were found in 24 out of 185 (13.0 %) cases. Among them, exon 2 p.G12C clinically relevant mutations were observed in 8 out 24 cases (33.3 %).

Conclusions

This review highlights the technical suitability of an NGS-based liquid biopsy system for the analysis of clinically relevant mutations in NSCLC patients.

Liquid Biopsies: Emerging role and clinical applications in solid tumours

Late detection and lack of precision diagnostics are the major challenges in cancer prevention and management. Biomarker discovery in specific cancers, especially at the pre-invasive stage, is vital for early diagnosis, positive treatment response, and good disease prognosis. Traditional diagnostic measures require invasive procedures such as tissue excision using a needle, an endoscope, and/or surgical resection which can be unsafe, expensive, and painful. Additionally, the presence of comorbid conditions in individuals might render them ineligible for undertaking a tissue biopsy, and in some cases, it is difficult to access tumours depending on the site of occurrence. In this context, liquid biopsies are being explored for their clinical significance in solid malignancies management. These non-invasive or minimally invasive methods are being developed primarily for identification of biomarkers for early diagnosis and targeted therapeutics. In this review, we have summarised the use and importance of liquid biopsy as significant tool in diagnosis, prognosis prediction, and therapeutic development. We have also discussed the challenges that are encountered and future perspective.

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.

The significance of tissue-agnostic biomarkers in solid tumors: the more the merrier?

INTRODUCTION

To date, several emerging biomarkers have gained considerable interest in the field of predictive molecular oncology. The advent of precision medicine has led to the development of innovative drugs targeting rare molecular pathways independently from histology, defined as tissue-agnostic drugs.

AREAS COVERED

Although there is a lot of promise for this new tissue-agnostic model in the oncological scenario, crucial issues from both the diagnostic and therapeutic standpoint are emerging. This review aims to critically examine the role of tissue-agnostic biomarkers in different solid tumors, focusing on the prevalence and methods of detection of agnostic biomarkers together with drug approvals to guide clinicians in this evolving landscape.

EXPERT OPINION

To strengthen the framework for tissue-agnostic approvals, the dialogue between regulatory, industrial, and academic parties should be intensified. Critical questions include the development of an efficient network system that can overcome the heterogeneity of patients' inclusion criteria along with the increasingly difficult interpretation of next-generation sequencing (NGS) profiling technologies. Cost-effectiveness and risk-benefit studies are needed in the national context considering the modalities of access to diagnostic tests and reimbursement of treatments.

Liquid Biopsies in Lung Cancer

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

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

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

Targeting KRASp.G12C Mutation in Advanced Non-Small Cell Lung Cancer: a New Era Has Begun

OPINION STATEMENT

KRASp.G12C mutation occurs in 12% of newly diagnosed advanced NSCLC and has recently emerged as a positive predictive biomarker for the selection of advanced NSCLC patients who may respond to novel KRASp.G12C inhibitors. The recent discovery of a new binding pocket under the effector region of KRAS G12C oncoprotein has made direct pharmacological inhibition of the KRASp.G12 mutation possible, leading to the clinical development of a new series of direct selective inhibitors, with a potential major impact on patients' survival and quality of life. Promising efficacy and tolerability data emerging from the early phase CodeBreak trial have already supported the regulatory approval of sotorasib as first in class targeted treatment for the second-line treatment of KRASp.G12C-positive NSCLC population, following immunotherapy-based first-line therapies, while the randomized phase III CodeBreak 200 clinical study has recently confirmed a significant superiority of sotorasib over docetaxel in terms of progression-free survival and quality of life. However, KRAS mutant NSCLC is a high heterogeneous disease characterized by a high rate of co-mutations, most frequently involving P53, STK11, and KEAP1 genes, which significantly modulate the composition of the tumor microenvironment and consequently affect clinical responses to both immunotherapy and targeted inhibitors now available in clinical practice. Both pre-clinical and clinical translational series have recently revealed a wide spectrum of resistance mechanisms occurring under selective KRASG12C inhibitors, including both on-target and off-target molecular alterations as well as morphological switching, negatively affecting the antitumor activity of these drugs when used as single agent therapies. The understanding of such biological background along with the emergence of pre-clinical data provided a strong rational to investigate different combination strategies, including the inhibition of SHP2, SOS1, and KRAS G12C downstream effectors, as well as the addition of immunotherapy and/or chemotherapy to targeted therapy. The preliminary results of these trials have recently suggested a promising activity of SHP2 inhibitors in the front-line setting, while toxicity issues limited the concurrent administration of immune-checkpoint inhibitors and sotorasib. The identification of predictive genomic/immunological biomarkers will be crucial to understand how to optimally sequencing/combining different drugs and ultimately personalize treatment strategies under clinical investigation, to definitively increase the survival outcomes of KRASp.G12C mutant advanced NSCLC patients.

The diagnostic accuracy of PIK3CA mutations by circulating tumor DNA in breast cancer: an individual patient data meta-analysis

Background

The circulating tumor DNA (ctDNA) diagnostic accuracy for detecting phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutations in breast cancer (BC) is under discussion. We aimed to compare plasma and tissue PIK3CA alterations, encompassing factors that could affect the results.

Methods

Two reviewers selected studies from different databases until December 2020. We considered BC patients with matched tumor tissue and plasma ctDNA. We performed meta-regression and subgroup analyses to explore sources of heterogeneity concerning tumor burden, diagnostic technique, sample size, sampling time, biological subtype, and hotspot mutation. Pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the related area under the curve (AUC) were elaborated for the overall population and each subgroup.

Results

The pooled analysis was carried out on 25 cohorts for a total of 1966 patients. The overall ctDNA sensitivity and specificity were 0.73 (95% CI: 0.70-0.77) and 0.87 (95% CI: 0.85-0.89). The AUC was 0.93. Pooled concordance, negative predictive value and positive predictive value values were 0.87 (95% CI: 0.82-0.92), 0.86 (95% CI: 0.81-0.90), and 0.89 (95% CI: 0.81-0.95) with pooled PLR, NLR, and DOR of 7.94 (95% CI: 4.90-12.86), 0.33 (95% CI: 0.25-0.45), and 33.41 (95% CI: 17.23-64.79), respectively. The pooled results consistently favored next-generation sequencing (NGS)- over polymerase chain reaction-based methodologies. The best ctDNA performance in terms of sensitivity, specificity, and AUC (0.85, 0.99, and 0.94, respectively) was observed in the low-time sampling subgroup (⩽18 days between tissue and plasma collection). Meta-regression and subgroup analyses highlighted sampling time as a possible major cause of heterogeneity.

Conclusions

These findings reliably estimate the high ctDNA accuracy for the detection of PIK3CA mutations. A ctDNA-first approach for the assessment of PIK3CA mutational status by NGS may accurately replace tissue tumor sampling, representing the preferable strategy at diagnosis of metastatic BC in patients who present with visceral involvement and at least two metastatic lesions, primarily given low clinical compliance or inaccessible metastatic sites.

Liquid Biopsy Analysis as a Tool for TKI-Based Treatment in Non-Small Cell Lung Cancer

The treatment of non-small cell lung cancer (NSCLC) has recently evolved with the introduction of targeted therapy based on the use of tyrosine kinase inhibitors (TKIs) in patients with certain gene alterations, including EGFR, ALK, ROS1, BRAF, and MET genes. Molecular targeted therapy based on TKIs has improved clinical outcomes in a large number of NSCLC patients with advanced disease, enabling significantly longer progression-free survival (PFS). Liquid biopsy is an increasingly popular diagnostic tool for treating TKI-based NSCLC. The studies presented in this article show that detection and analysis based on liquid biopsy elements such as circulating tumor cells (CTCs), cell-free DNA (cfDNA), exosomes, and/or tumor-educated platelets (TEPs) can contribute to the appropriate selection and monitoring of targeted therapy in NSCLC patients as complementary to invasive tissue biopsy. The detection of these elements, combined with their molecular analysis (using, e.g., digital PCR (dPCR), next generation sequencing (NGS), shallow whole genome sequencing (sWGS)), enables the detection of mutations, which are required for the TKI treatment. Despite such promising results obtained by many research teams, it is still necessary to carry out prospective studies on a larger group of patients in order to validate these methods before their application in clinical practice.

KRAS mutated Non-Small Lung Carcinoma: A Real World Context from the Indian subcontinent

BACKGROUND

KRAS, although a common variant of occurrence (~20% of non-small-cell lung carcinoma [NSCLC]) has been untargetable, owing to the molecular structure which inherently prevents drug binding. KRAS mutations in NSCLC are associated with distinct clinical profiles including smokers and mucinous histology. KRAS G12C mutations account for ~40% KRAS altered NSCLC, but NSCLC being a geographically diverse disease, the features may be distinct in this part of the world. This is a single-center experience of KRAS-mutated NSCLC including clinical, imaging, pathologic features, and treatment patterns and outcomes.

METHODS

This is a single-center retrospective study of KRAS-mutated NSCLC. The clinicopathological features and outcomes were retrieved and collated from the medical record archives of the hospital.

RESULTS

Fifty (30.6%) patients with advanced-stage NSCLC with alterations in the KRAS gene were enrolled in the 163 patients who were tested for KRAS alterations. The median age was 61 years. Molecular detection revealed three main types of KRAS mutations viz-a-vis: G12C in 17 (34%), G12V in 9 (18%), and G12D in 6 (12%) patients. Comparing G12C versus the non-G12C mutated cases, co-mutations were common in the non-G12C subgroup (p < 0.05). Among the 36, who were treated at our center, all received chemotherapy as the first line with a median progression-free survival (PFS)of 5.4 months. The PFS of G12C was higher than the non-G12C subgroup (6.4 vs 3.8 months).

CONCLUSION

This is the largest single-center experience from the Indian subcontinent for KRAS-mutated NSCLC with distinct clinical features. It highlights the unmet need for G12C inhibitors in our country, where prevalence is equivalent to the West.

Current treatments for non-small cell lung cancer

Despite improved methods of diagnosis and the development of different treatments, mortality from lung cancer remains surprisingly high. Non-small cell lung cancer (NSCLC) accounts for the large majority of lung cancer cases. Therefore, it is important to review current methods of diagnosis and treatments of NSCLC in the clinic and preclinic. In this review, we describe, as a guide for clinicians, current diagnostic methods and therapies (such as chemotherapy, chemoradiotherapy, targeted therapy, antiangiogenic therapy, immunotherapy, and combination therapy) for NSCLC.

Targeting Mutant Kirsten Rat Sarcoma Viral Oncogene Homolog in Non-Small Cell Lung Cancer: Current Difficulties, Integrative Treatments and Future Perspectives

In the past few decades, several gene mutations, including the anaplastic lymphoma kinase, epidermal growth factor receptor, ROS proto-oncogene 1 and rat sarcoma viral oncogene homolog (RAS), have been discovered in non-small cell lung cancer (NSCLC). Kirsten rat sarcoma viral oncogene homolog (KRAS) is the isoform most frequently altered in RAS-mutated NSCLC cases. Due to the structural and biochemical characteristics of the KRAS protein, effective approaches to treating KRAS-mutant NSCLC still remain elusive. Extensive recent research on KRAS-mutant inhibitors has made a breakthrough in identifying the covalent KRASG12C inhibitor as an effective agent for the treatment of NSCLC. This review mainly concentrated on introducing new covalent KRASG12C inhibitors like sotorasib (AMG 510) and adagrasib (MRTX 849); summarizing inhibitors targeting the KRAS-related upstream and downstream effectors in RAF/MEK/ERK pathway and PI3K/AKT/mTOR pathway; exploring the efficacy of immunotherapy and certain emerging immune-related therapeutics such as adoptive cell therapy and cancer vaccines. These inhibitors are being investigated in clinical trials and have exhibited promising effects. On the other hand, naturally extracted compounds, which have exhibited safe and effective properties in treating KRAS-mutant NSCLC through suppressing the MAPK and PI3K/AKT/mTOR signaling pathways, as well as through decreasing PD-L1 expression in preclinical studies, could be expected to enter into clinical studies. Finally, in order to confront the matter of drug resistance, the ongoing clinical trials in combination treatment strategies were summarized herein.

Daily Practice Assessment of KRAS Status in NSCLC Patients: A New Challenge for the Thoracic Pathologist Is Right around the Corner

Simple Summary

RAS mutation is the most frequent oncogenic alteration in human cancers and KRAS is the most frequently mutated, notably in non-small cell lung carcinomas (NSCLC). Various attempts to inhibit KRAS in the past were unsuccessful in these latter tumors. However, recently, several small molecules (AMG510, MRTX849, JNJ-74699157, and LY3499446) have been developed to specifically target KRAS G12C-mutated tumors, which seems promising for patient treatment and should soon be administered in daily practice for non-squamous (NS)-NSCLC. In this context, it will be mandatory to systematically assess the KRAS status in routine clinical practice, at least in advanced NS-NSCLC, leading to new challenges for thoracic oncologists.

Abstract

KRAS mutations are among the most frequent genomic alterations identified in non-squamous non-small cell lung carcinomas (NS-NSCLC), notably in lung adenocarcinomas. In most cases, these mutations are mutually exclusive, with different genomic alterations currently known to be sensitive to therapies targeting EGFR, ALK, BRAF, ROS1, and NTRK. Recently, several promising clinical trials targeting KRAS mutations, particularly for KRAS G12C-mutated NSCLC, have established new hope for better treatment of patients. In parallel, other studies have shown that NSCLC harboring co-mutations in KRAS and STK11 or KEAP1 have demonstrated primary resistance to immune checkpoint inhibitors. Thus, the assessment of the KRAS status in advanced-stage NS-NSCLC has become essential to setting up an optimal therapeutic strategy in these patients. This stimulated the development of new algorithms for the management of NSCLC samples in pathology laboratories and conditioned reorganization of optimal health care of lung cancer patients by the thoracic pathologists. This review addresses the recent data concerning the detection of KRAS mutations in NSCLC and focuses on the new challenges facing pathologists in daily practice for KRAS status assessment.

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

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

A narrative review on the implementation of liquid biopsy as a diagnostic tool in thoracic tumors during the COVID-19 pandemic

Objective

In this review, we evaluate the role of liquid biopsy in managing lung cancer patients during the still ongoing coronavirus disease 2019 (COVID-19) healthcare emergency.

Background

The novel influenza coronavirus (severe acute respiratory syndrome coronavirus or SARS-CoV-2) has upended several aspects of our lives, including medical activities. In this setting, many routine cancer diagnostic and therapeutic procedures have been suspended, leading to delays in diagnosis, treatments, and, ultimately, increases in cancer mortality rates. Equally drastic has been the impact of COVID-19 on clinical trials, many of which have been stalled or have never begun. This has left many patients who were hoping to receive innovative treatments in a limbo. Although, as of today, the introduction of drastic security measures has been crucially important to contain the pandemic, one cannot ignore the need to continue providing chronically ill patients all the health care they need, in terms of detection, prevention, and treatment. In these unprecedented times, liquid biopsy, more than ever before, may play a relevant role in the adequate management of these frail patients.

Methods

we performed a deep analysis of the recent international literature published in English on PUBMED in the last six months focused on the impact of SARS-CoV-2 on the management of lung cancer patients, focusing the attention on the role of liquid biopsy.

Conclusions

COVID-19 pandemic has significantly modified our lives and overall medical practice. In these unprecedented times, liquid biopsy may represent a valid and less time-consuming diagnostic approach than conventional tissue and cytological specimens.

Rapid Multiplex Strip Test for the Detection of Circulating Tumor DNA Mutations for Liquid Biopsy Applications

In the era of personalized medicine, molecular profiling of patient tumors has become the standard practice, especially for patients with advanced disease. Activating point mutations of the KRAS proto-oncogene are clinically relevant for many types of cancer, including colorectal cancer (CRC). While several approaches have been developed for tumor genotyping, liquid biopsy has been gaining much attention in the clinical setting. Analysis of circulating tumor DNA for genetic alterations has been challenging, and many methodologies with both advantages and disadvantages have been developed. We here developed a gold nanoparticle-based rapid strip test that has been applied for the first time for the multiplex detection of KRAS mutations in circulating tumor DNA (ctDNA) of CRC patients. The method involved ctDNA isolation, PCR-amplification of the KRAS gene, multiplex primer extension (PEXT) reaction, and detection with a multiplex strip test. We have optimized the efficiency and specificity of the multiplex strip test in synthetic DNA targets, in colorectal cancer cell lines, in tissue samples, and in blood-derived ctDNA from patients with advanced colorectal cancer. The proposed strip test achieved rapid and easy multiplex detection (normal allele and three major single-point mutations) of the clinically relevant KRAS mutations in ctDNA in blood samples of CRC patients with high specificity and repeatability. This multiplex strip test represents a minimally invasive, rapid, low-cost, and promising diagnostic tool for the detection of clinically relevant mutations in cancer patients.

Targeting KRAS in Non-Small Cell Lung Cancer

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) is the most frequently altered oncogene in Non-Small Cell Lung Cancer (NSCLC). KRAS mutant tumors constitute a heterogeneous group of diseases, different from other oncogene-derived tumors in terms of biology and response to treatment, which hinders the development of effective drugs against KRAS. Therefore, for decades, despite enormous efforts invested in the development of drugs aimed at inhibiting KRAS or its signaling pathways, KRAS was considered to be undruggable. Recently, the discovery of a new pocket under the effector binding switch II region of KRAS G12C has allowed the development of direct KRAS inhibitors such as sotorasib, the first FDA-approved drug targeting KRAS G12C, or adagrasib, initiating a new exciting era. However, treatment with targeted KRAS G12C inhibitors also leads to resistance, and understanding the possible mechanisms of resistance and which drugs could be useful to overcome it is key. Among others, KRAS G12C (ON) tricomplex inhibitors and different combination therapy strategies are being analyzed in clinical trials. Another area of interest is the potential role of co-mutations in treatment selection, particularly immunotherapy. The best first-line strategy remains to be determined and, due to the heterogeneity of KRAS, is likely to be based on combination therapies.

KRAS and MET in non-small-cell lung cancer: two of the new kids on the 'drivers' block

Non-small-cell lung cancer (NSCLC) is a heterogeneous disease, and therapeutic management has advanced to identify various critical oncogenic mutations that promote lung cancer tumorigenesis. Subsequent studies have developed targeted therapies against these oncogenes in the hope of personalized treatment based on the tumor's molecular genomics. This review presents a comprehensive review of the biology, new therapeutic interventions, and resistance patterns of two well-defined subgroups, tumors with KRAS and MET alterations. We also discuss the status of molecular testing practices for these two key oncogenic drivers, considering the progressive introduction of next-generation sequencing (NGS) and RNA sequencing in regular clinical practice.

Comparison of Two Blood-Based Genotyping Tests to Investigate the KRAS G12C Mutation in Patients with Non-Small-Cell Lung Cancer at Failure of First-Line Treatments

Although molecular profiling at diagnosis has traditionally relied on direct sampling of neoplastic tissue, cancer clonal evolution represents a critical obstacle to use primary tissue biopsies to guide clinical decision-making at the time of progressive disease. Liquid biopsies might offer enormous advantages over tissue biopsies, tracking in real-time temporal-based tumor dynamics following each line of treatment. Here, we compared two liquid biopsy assays, specifically real-time polymerase chain reaction and next-generation sequencing, to track the KRAS G12C mutation at onset of progression from previous lines of therapy. The KRAS G12C mutation was acquired at the time of progressive disease in 24% of patients. Furthermore, all patients with KRAS G12C mutation-positive tissue became negative in ctDNA at progressive disease. The presence of other somatic mutations in all these samples confirmed the tumor origin of the circulating DNA. This pilot study suggests that in the assessment of the plasma KRAS G12C mutation as a druggable target, real-time PCR assay Idylla might be a suitable approach to better match patients to interventional biomarker-targeted therapies.

Liquid biopsy from research to clinical practice: focus on non-small cell lung cancer

INTRODUCTION

In the current era of personalized medicine, liquid biopsy has acquired a relevant importance in patient management of advanced stage non-small cell lung cancer (NSCLC). As a matter of fact, liquid biopsy may supplant the problem of inadequate tissue for molecular testing. The term 'liquid biopsy' refers to a number of different biological fluids, but is most clearly associated with plasma-related platforms. It must be taken into account that pre-analytical processing and the selection of the appropriate technology according to the clinical context may condition the results obtained. In addition, novel clinical applications beyond the evaluation of the molecular status of predictive biomarkers are currently under investigation.

AREAS COVERED

This review summarizes the available evidence on pre-analytical issues and different clinical applications of liquid biopsies in NSCLC patients.

EXPERT OPINION

Liquid biopsy should be considered not only as a valid alternative but as complementary to tissue-based molecular approaches. Careful attention should be paid to the optimization and standardization of all phases of liquid biopsy samples management in order to determine a significant improvement in either sensitivity or specificity, while significant reducing the number of 'false negative' or 'false positive' molecular results.

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

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

On target: Rational approaches to KRAS inhibition for treatment of non-small cell lung carcinoma

Non-small cell lung carcinoma (NSCLC) is a leading cause of cancer death. Approximately one-third of patients with NSCLC have a KRAS mutation. KRAS^G12C, the most common mutation, is found in ~13% of patients. While KRAS was long considered 'undruggable', several novel direct KRAS^G12C inhibitors have shown encouraging signs of efficacy in phase I/II trials and one of these (sotorasib) has recently been approved by the US Food and Drug Administration. This review examines the role of KRAS mutations in NSCLC and the challenges in targeting KRAS. Based on specific KRAS biology, it reports exciting progress, exploring the use of novel direct KRAS inhibitors as monotherapy or in combination with other targeted therapies, chemotherapy, and immunotherapy.

Liquid Biopsy Analysis in Clinical Practice: Focus on Lung Cancer

Lung cancer is the leading cause of cancer death worldwide. Despite the emergence of highly effective targeted therapies, up to 30% of advanced stage non-small cell lung cancer (NSCLC) patients do not undergo tissue molecular testing because of scarce tissue availability. Liquid biopsy, on the other hand, offers these patients a valuable opportunity to receive the best treatment options in a timely manner. Indeed, besides being much faster and less invasive than conventional tissue-based analysis, it can also yield specific information about the genetic make-up and evolution of patients’ tumors. However, several issues, including lack of standardized protocols for sample collection, processing, and interpretation, still need to be addressed before liquid biopsy can be fully incorporated into routine oncology practice. Here, we reviewed the most important challenges hindering the implementation of liquid biopsy in oncology practice, as well as the great advantages of this approach for the treatment of NSCLC patients.

Virtual clinical trial simulations for a novel KRASG12C inhibitor (ASP2453) in non-small cell lung cancer

KRAS is a small GTPase family protein that relays extracellular growth signals to cell nucleus. KRAS^G12C mutations lead to constitutive proliferation signaling and are prevalent across human cancers. ASP2453 is a novel, highly potent, and selective inhibitor of KRAS^G12C . Although preclinical data suggested impressive efficacy, it remains unclear whether ASP2453 will show more favorable clinical response compared to more advanced competitors, such as AMG 510. Here, we developed a quantitative systems pharmacology (QSP) model linking KRAS signaling to tumor growth in patients with non-small cell lung cancer. The model was parameterized using in vitro ERK1/2 phosphorylation and in vivo xenograft data for ASP2453. Publicly disclosed clinical data for AMG 510 were used to generate a virtual population, and tumor size changes in response to ASP2453 and AMG 510 were simulated. The QSP model predicted ASP2453 exhibits greater clinical response than AMG 510, supporting potential differentiation and critical thinking for clinical trials.

Non-Small Cell Lung Cancer Harboring Concurrent EGFR Genomic Alterations: A Systematic Review and Critical Appraisal of the Double Dilemma

The molecular pathways which promote lung cancer cell features have been broadly explored, leading to significant improvement in prognostic and diagnostic strategies. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have dramatically altered the treatment approach for patients with metastatic non-small cell lung cancer (NSCLC). Latest investigations by using next-generation sequencing (NGS) have shown that other oncogenic driver mutations, believed mutually exclusive for decades, could coexist in EGFR-mutated NSCLC patients. However, the exact clinical and pathological role of concomitant genomic aberrations needs to be investigated. In this systematic review, we aimed to summarize the recent data on the oncogenic role of concurrent genomic alterations, by specifically evaluating the characteristics, the pathological significance, and their potential impact on the treatment approach.

What Is New in Biomarker Testing at Diagnosis of Advanced Non-Squamous Non-Small Cell Lung Carcinoma? Implications for Cytology and Liquid Biopsy

The discovery and clinical validation of biomarkers predictive of the response of non-squamous non-small-cell lung carcinomas (NS-NSCLC) to therapeutic strategies continue to provide new data. The evaluation of novel treatments is based on molecular analyses aimed at determining their efficacy. These tests are increasing in number, but the tissue specimens are smaller and smaller and/or can have few tumor cells. Indeed, in addition to tissue samples, complementary cytological and/or blood samples can also give access to these biomarkers. To date, it is recommended and necessary to look for the status of five genomic molecular biomarkers (EGFR, ALK, ROS1, BRAFV600, NTRK) and of a protein biomarker (PD-L1). However, the short- and more or less long-term emergence of new targeted treatments of genomic alterations on RET and MET, but also on others’ genomic alteration, notably on KRAS, HER2, NRG1, SMARCA4, and NUT, have made cellular and blood samples essential for molecular testing. The aim of this review is to present the interest in using cytological and/or liquid biopsies as complementary biological material, or as an alternative to tissue specimens, for detection at diagnosis of new predictive biomarkers of NS-NSCLC.

The prognostic impact of tumor mutational burden (TMB) in the first-line management of advanced non-oncogene addicted non-small-cell lung cancer (NSCLC): a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The role of tumor mutational burden (TMB) is still debated for selecting advanced non-oncogene addicted non-small-cell lung cancer (NSCLC) patients who might benefit from immune checkpoint inhibitors (ICIs). Of note, TMB failed to predict a benefit in overall survival (OS) among such patients.

MATERIALS AND METHODS

The purpose of this meta-analysis was to compare efficacy outcomes among first-line immune-oncology (IO) agents versus standard platinum-based chemotherapy (CT) within two subgroups (TMB-low and TMB-high on either tissue or blood). We collected hazard ratios (HRs) to evaluate the association for progression-free survival (PFS) and OS, with the relative 95% confidence intervals (CIs). Risk ratios (RRs) were used as an association measure for objective response rate (ORR).

RESULTS

Eight different cohorts of five randomized controlled phase III studies (3848 patients) were analyzed. In TMB-high patients, IO agents were associated with improved ORR (RRs 1.37, 95% CI 1.13-1.66), PFS (HR 0.69, 95% CI 0.61-0.79) and OS (HR 0.67, 95% CI 0.59-0.77) when compared with CT, thus suggesting a possible predictive role of high TMB for IO regimens. In TMB-low patients, the IO strategy did not lead to any significant benefit in survival and activity, whereas the pooled results of both ORR and PFS were intriguingly associated with a statistical significance in favor of CT.

CONCLUSIONS

This meta-analysis resulted in a proven benefit in OS in favor of IO agents in the TMB-high population. Although more prospective data are warranted, we postulated the hypothesis that monitoring TMB, in addition to the existing programmed death-ligand 1 (PD-L1) expression level, could represent the preferable option for future clinical research in the first-line management of advanced non-oncogene addicted NSCLC patients.

Urine as a Source of Liquid Biopsy for Cancer

Simple Summary

Tissue biopsy is essential for diagnosis and characterization of a tumor. Recently circulating tumor cells and other tumor-derived nucleic acid can be detected from blood, which is called liquid biopsy. Now this concept has been expanded to many other body fluids including urine. Urine is the least invasive method to obtain a liquid biopsy and can be done anywhere, which allows longitudinal repeated sampling. Here, we review the latest update on urine liquid biopsy in urological and non-urological cancers.

Abstract

Tissue biopsy is the gold standard for diagnosis and morphological and immunohistochemical analyses to characterize cancer. However, tissue biopsy usually requires an invasive procedure, and it can be challenging depending on the condition of the patient and the location of the tumor. Even liquid biopsy analysis of body fluids such as blood, saliva, gastric juice, sweat, tears and cerebrospinal fluid may require invasive procedures to obtain samples. Liquid biopsy can be applied to circulating tumor cells (CTCs) or nucleic acids (NAs) in blood. Recently, urine has gained popularity due to its less invasive sampling, ability to easily repeat samples, and ability to follow tumor evolution in real-time, making it a powerful tool for diagnosis and treatment monitoring in cancer patients. With the development and advancements in extraction methods of urinary substances, urinary NAs have been found to be closely related to carcinogenesis, metastasis, and therapeutic response, not only in urological cancers but also in non-urological cancers. This review mainly highlights the components of urine liquid biopsy and their utility and limitations in oncology, especially in non-urological cancers.

Generation of Non-Small Cell Lung Cancer Patient-Derived Xenografts to Study Intratumor Heterogeneity

Simple Summary

It is widely thought that tumors are composed of different subpopulations of cancer cells carrying genetic alterations with some of them being common among all cells while others are unique for each subpopulation. This variable genetic profile of tumor cells is a component of what is collectively described as intratumor heterogeneity (ITH). Surviving the immune system and therapies, and establishing metastases are forces of natural selection that act upon ITH and drive tumor evolution and, eventually, the clinical presentation of patients. The aim of this prospective study was to investigate ITH in early-stage operable non-small cell lung cancer. We directly grafted human tumors in immunosuppressed mice and compared the genetic profile of the tumors grown in mice with that of the original human tumors. We identified clinical factors that affected the ability of human tumors to grow as mouse xenografts.

Abstract

Recent advances in sequencing technologies have allowed the in-depth molecular study of tumors, even at the single cell level. Sequencing efforts have uncovered a previously unappreciated heterogeneity among tumor cells, which has been postulated to be the driving force of tumor evolution and to facilitate recurrence, metastasis, and drug resistance. In the current study, focused on early-stage operable non-small cell lung cancer, we used tumor growth in patient-derived xenograft (PDX) models in mice as a fast-forward tumor evolution process to investigate the molecular characteristics of tumor cells that grow in mice, as well as the parameters that affect the grafting efficiency. We found that squamous cell carcinomas grafted significantly more efficiently compared with adenocarcinomas. Advanced stage, patient age and primary tumor size were positively correlated with grafting. Additionally, we isolated and characterized circulating tumor cells (CTC) from patients’ peripheral blood and found that the presence of CTCs expressing epithelial-to-mesenchymal (EMT) markers correlated with the grafting potential. Interestingly, exome sequencing of the PDX tumor identified genetic alterations in DNA repair and genome integrity genes that were under-represented in the human primary counterpart. In conclusion, through the generation of a PDX biobank of NSCLC, we identified the clinical and molecular properties of tumors that affected growth in mice.

Next-Generation Sequencing with Liquid Biopsies from Treatment-Naïve Non-Small Cell Lung Carcinoma Patients

Recently, the liquid biopsy (LB), a non-invasive and easy to repeat approach, has started to compete with the tissue biopsy (TB) for detection of targets for administration of therapeutic strategies for patients with advanced stages of lung cancer at tumor progression. A LB at diagnosis of late stage non-small cell lung carcinoma (NSCLC) is also being performed. It may be asked if a LB can be complementary (according to the clinical presentation or systematics) or even an alternative to a TB for treatment-naïve advanced NSCLC patients. Nucleic acid analysis with a TB by next-generation sequencing (NGS) is gradually replacing targeted sequencing methods for assessment of genomic alterations in lung cancer patients with tumor progression, but also at baseline. However, LB is still not often used in daily practice for NGS. This review addresses different aspects relating to the use of LB for NGS at diagnosis in advanced NSCLC, including its advantages and limitations.

Predictive molecular pathology in the time of COVID-19

AIMS

In the time of COVID-19, predictive molecular pathology laboratories must still timely select oncological patients for targeted treatments. However, the need to respect social distancing measures may delay results generated by laboratory-developed tests based on sequential steps a long hands-on time. Laboratory workflows should now be simplified.

METHODS

The organisation of the University of Naples Federico II predictive pathology laboratory was assessed before (March-April 2019) and during (March-April 2020) the Italian lockdown.

RESULTS

The number of patients undergoing single or multiple biomarker testing was similar in 2019 (n=43) and in 2020 (n=45). Considering adequate samples for molecular testing, before the outbreak, next-generation sequencing was mostly used (35/42, 83.3%). Testing six genes had a reagent cost of €98/patient. Conversely, in 2020, almost all cases (38/41, 92.7%) were analysed by automated testing. This latter had for any single assay/gene a significant reagent cost (€95-€136) and a faster mean turnaround time (5.3 vs 7.9 working days).

CONCLUSION

In the times of coronavirus, laboratory fully automated platforms simplify predictive molecular testing. Laboratory staff may be more safely and cost-effectively managed.

Next generation sequencing for liquid biopsy based testing in non-small cell lung cancer in 2021

Lung cancer is the leading cause of cancer death worldwide, with non-small cell lung cancer (NSCLC) representing its most commonly diagnosed sub-type. Despite the significant improvements in lung cancer biomarkers knowledge, accompanied by substantial technological advances in molecular tumor profiling, a considerable fraction (up to 30 %) of advanced NSCLC patient presents with major testing challenges or tissue unavailability for molecular analysis. In this context, liquid biopsy is on the rise, currently gaining considerable interest within the molecular pathology and oncology community. Molecular profiling of liquid biopsy specimens using next generation molecular biology methodologies is a rapidly evolving field with promising applications not exclusively limited to advanced stages but also more recently expanding to early stages cancer patients. Here, we offer an overview of some of the most consolidated and emerging applications of next generation sequencing technologies for liquid biopsy testing in NSCLC.

Second medical opinion in oncological setting

Oncological patients increasingly require second medical opinions to feel more likely confident with their oncologists and treatments, although this could lead to wrong opinions and delay in the start of treatments. Second opinions can be required also by physicians to obtain advices, especially in case of rare tumors. The request of new opinions is documented in radiology and pathology settings too, with not negligible discrepancy rate. Conversely, the role in general medical/surgical conditions has not been well established. Literature is poor of studies relative to second opinions or they are more focused on patient's motivations. For these reasons, AIOM (Italian Association of Medical Oncology) and AIOM Foundation faced this topic during the 7th Annual Meeting on Ethics in Oncology (Ragusa, 4-5 t h May 2018). In this position paper we report reasons, limits, advantages and outcomes of second medical opinion and the respective Decalogue in the oncological setting.

Performance evaluation of a fully closed real-time PCR platform for the detection of KRAS p.G12C mutations in liquid biopsy of patients with non-small cell lung cancer

Whenever tissue sample is not available, non-small cell lung cancer (NSCLC) biomarker testing is performed with liquid biopsy. The Kirsten rat sarcoma viral oncogene homolog (KRAS) p.G12C mutation is a novel target in patients with NSCLC. In this study, 33 NSCLC frozen plasma samples, previously characterised for KRAS mutational status by next generation sequencing (NGS), were processed by the fully automated Idylla KRAS assay. In 30/33 cases, archival matched cell-free DNA (cfDNA) was also directly pipetted in the cartridge. Overall, 30/33 plasma and 28/30 cfDNA samples yielded valid results. In 29/30 of KRAS p.G12C mutant plasma samples and 26/28 of cfDNA, Idylla confirmed the NGS results. In conclusion, the Idylla NSCLC KRAS liquid biopsy assay may represent a reliable tool to assess KRAS p.G12C mutation.

The Emerging Therapeutic Landscape of ALK Inhibitors in Non-Small Cell Lung Cancer

The treatment of metastatic non-small cell lung cancer (NSCLC) has undergone a paradigm shift over the last decade. Better molecular characterization of the disease has led to the rapid improvement of personalized medicine and the prompt delivery of targeted therapies to patients with NSCLC. The discovery of the EML4-ALK fusion gene in a limited subset of patients affected by NSCLC and the subsequent clinical development of crizotinib in 2011 has been an impressive milestone in lung cancer research. Unfortunately, acquired resistances regularly develop, hence disease progression occurs. Afterward, modern tyrosine kinase inhibitors (TKIs), such as ceritinib, alectinib, brigatinib, and lorlatinib, have been approved by the Food and Drug Administration (FDA) for the management of anaplastic lymphoma kinase (ALK)-positive NSCLCs. Several compounds are currently under investigation to achieve the optimal strategy of therapy. Additionally, the results of ongoing clinical trials with novel-generation TKI will provide more evidence on the best sequence in the treatment of ALK-positive NSCLC patients. In this review, we provide a comprehensive overview of the state-of-the-art targeted therapy options in ALK-positive NSCLCs. Resistance, potential therapeutic strategies to overcome drug resistance, and future perspectives for this subset of patients are critically analyzed and summarized.

Liquid biopsy for BRAF mutations testing in non-small cell lung cancer: a retrospective study

V-Raf murine sarcoma viral oncogene homolog B (BRAF) gene mutations have recently been approved to select advanced stages non-small cell lung cancer (NSCLC) patients for tyrosine kinase inhibitors treatments. In this setting, liquid biopsy may represent a valuable option for BRAF mutational testing in patients without tissue availability. Here, we reviewed 196 plasma based liquid biopsies analysed by an in-house developed next generation sequencing panel, termed SiRe. On the overall, 6 (3.1%) out of 196 BRAF mutated cases were identified, with an overall median allelic frequency of 3.4%. Exon 15 p.V600E was the most common detected mutation (2/6, 33.3%). Our data highlighted that the SiRe panel is a robust tool for BRAF mutation assessment on circulating tumour DNA. Further investigation is required to develop a diagnostic algorithm to harmonise BRAF testing on tissue and blood in advanced stages NSCLC patients.

BRAF: A Two-Faced Janus

Gain-of-function of V-Raf Murine Sarcoma Viral Oncogene Homolog B (BRAF) is one of the most frequent oncogenic mutations in numerous cancers, including thyroid papillary carcinoma, melanoma, colon, and lung carcinomas, and to a lesser extent, ovarian and glioblastoma multiforme. This mutation aberrantly activates the mitogen-activated protein (MAP) kinase extracellular signal-regulated kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathway, thereby eliciting metastatic processes. The relevance of BRAF mutations stems from its prognostic value and, equally important, from its relevant therapeutic utility as an actionable target for personalized treatment. Here, we discuss the double facets of BRAF. In particular, we argue the need to implement diagnostic molecular algorithms that are able to detect this biomarker in order to streamline and refine diagnostic and therapeutic decisions.