Healthcare disparities, screening, and molecular testing in the changing landscape of non-small cell lung cancer in the United States: a review.

Inequitable access to care continues to hinder improvements in diagnosis and treatment of lung cancer. This review describes healthcare disparities in the changing landscape of non-small cell lung cancer (NSCLC) in the United States, focusing on racial, ethnic, sex-based, and socioeconomic trends. Furthermore, strategies to address disparities, overcome challenges, and improve patient outcomes are proposed. Barriers exist across lung cancer screening, diagnosis, and treatment regimens, varying by sex, age, race and ethnicity, geography, and socioeconomic status. Incidence and mortality rates of lung cancer are higher among Black men than White men, and incidences in young women are substantially greater than in young men. Disparities may be attributed to geographic differences in screening access, with correlating higher incidence and mortality rates in rural versus urban areas. Lower socioeconomic status is also linked to lower survival rates. Several strategies could help reduce disparities and improve outcomes. Current guidelines could improve screening eligibility by incorporating sex, race, and socioeconomic status variables. Patient and clinician education on screening guidelines and patient-level barriers to care are key, and biomarker testing is critical since ~ 70% of patients with NSCLC have an actionable biomarker. Timely diagnosis, staging, and comprehensive biomarker testing, including cell-free DNA liquid biopsy, may provide valuable treatment guidance for patients with NSCLC. Efforts to improve lung cancer screening and biomarker testing access, decrease bias, and improve education about screening and testing are needed to reduce healthcare disparities in NSCLC.

Modeling health outcomes associated with BRCA testing and treatment strategies for patients with metastatic pancreatic cancer.

BACKGROUND: Germline BRCA mutations (gBRCAm) occur in 4%-8% patients with metastatic pancreatic cancer (mPC); guidelines recommend platinum-based chemotherapies and olaparib maintenance in this population. We evaluated, through modeling, the role of treatments and gBRCA testing on health outcomes of mPC patients. METHODS: A decision tree/partitioned survival model was developed to assess lifetime health outcomes for four strategies: 1) no testing; 2) early testing/no olaparib maintenance; 3) early testing (i.e., before 1L treatment)/olaparib maintenance; and 4) late testing/olaparib maintenance. Treatment patterns were assumed to follow current practice in the United States. Overall survival and progression-free survival curves were extrapolated from pivotal trials, including POLO trial for outcomes from olaparib maintenance after at least 16 weeks of platinum-based chemotherapy. RESULTS: Among patients with gBRCAm, almost twice as many patients received platinum-based regimens in strategies involving early testing compared to when early testing was not employed (78.7 % vs 40.2 %). Health outcomes were highest in the strategy with early testing and available olaparib treatment whether considering progression-free life years (PF LYs, 1.27 vs 0.55-0.87), LYs (1.82 vs 0.95-1.27) or quality adjusted life years (QALYs, 1.15 vs 0.73-0.92 for others). Consistent patterns of results were observed in the overall cohort of mPC patients (i.e., irrespective of gBRCAm). CONCLUSION: Patients with mPC achieved longest health outcomes (as measured by mean PF LYs, LYs and QALYs) with a scenario of early gBRCA testing and availability of olaparib maintenance. The results were primarily driven by improved health outcomes associated with higher efficacy of platinum-based chemotherapies and olaparib used in gBRCAm patients.

EGFR mutation testing, treatment and survival in stage I-III non-small-cell lung cancer: CancerLinQ Discovery database retrospective analysis.

Aim: To describe real-world biomarker testing, treatment and survival in stage IA-IIIC non-small-cell lung cancer (NSCLC). Methods: Electronic records of USA-based patients in the CancerLinQ Discovery® database with stage IA-IIIC NSCLC (diagnosed between 2014 and 2018) were screened; a curated cohort of 14,452 records was identified for further analysis. Results: Of 3121 (21.6%) patients who had EGFR testing, 493 (15.8%) were EGFR-mutation positive. Of 974 patients who underwent surgical resection, 513 (52.7%) received adjuvant therapy. A quarter of patients with EGFR-mutation positive NSCLC received targeted adjuvant therapy. Conclusion: Approximately a fifth of patients underwent EGFR testing; biomarker testing is important to ensure optimal outcomes for patients with stage I-III NSCLC.

A study investigating how many patients with early-stage non-small-cell lung cancer (NSCLC) had mutations in a protein called EGFR and which treatments they received in routine clinical practice: The treatment recommended by medical experts for stage IA­IIIA non-small-cell lung cancer (NSCLC) is surgical removal of the growth (tumor). Patients with stage II or III, and some with stage IB disease, are recommended to receive treatment with medications such as chemotherapy or oral cancer treatments after surgery (adjuvant treatment). In some lung cancers, there are mutations in a protein called EGFR. Osimertinib, a drug that blocks the activity of mutated EGFR on cancer cells, reducing their growth and spread, is recommended as an adjuvant treatment for patients with EGFR-mutated, stage IB­IIIA NSCLC. This study aimed to understand how many patients with stage I­III NSCLC have tumors with EGFR mutations, and which treatments patients received in everyday clinical practice, before new medicines such as osimertinib (that treat EGFR-mutated NSCLC) were recommended. We looked at anonymous data from 14,452 patients with stage I­III NSCLC treated at cancer clinics in the USA between 2014 and 2018. We found that 3121 (21.6%) patients had an EGFR mutation test and 493 (15.8%) had EGFR-mutation positive NSCLC. Of patients who had surgery to remove the tumor, 55% received adjuvant therapy (treatment after surgery). It is important to perform EGFR mutation testing in patients with stage IB­IIIA NSCLC so that patients with EGFR-mutation positive NSCLC can receive appropriate treatment.

A review of the directly sampled endometrial cytology on LBC samples: Classification, microscopic criteria and beyond.

The Yokohama System for Reporting Endometrial Cytology (TYS) has been proposed by an expert meeting under the auspices of the International Academy of Cytology (IAC) in May 2016 at the IAC in Yokohama. Since its introduction, the TYS has been receiving worldwide acceptance, and this review aims to assess its global impact. The adoption of endometrial cytology as a diagnostic procedure has been hampered in the past by difficulties arising in interpreting the cellular findings due to a number of factors (such as excess blood, cellular overlapping and the complex physiology of endometrium). Recently, the use of liquid-based cytology (LBC), with its ability to remove blood and mucus and to distribute cells uniformly in a thin layer on the slide, has provided an opportunity to re-evaluate the role of endometrial cytology. LBC is a useful tool in the cytologic diagnosis and follow-up of endometrial abnormalities, which remains complementary to the emerging molecular diagnostic cytopathology. The study of LBC from endometrial cytology could be challenging since it is affected by numerous look-alikes and diagnostic pitfalls. This review discusses these various entities and takes into consideration the ancillary techniques that may be useful in the diagnostic procedure. In conclusion, our review of the published data suggests that the TYS is a valid classification scheme that has been widely accepted by cytopathologists globally, is highly reproducible and makes a valuable contribution to clinical therapeutic management. At present, molecular cytopathology is a rapidly evolving field of modern cytopathology, which underlines the effective interplay between genomics and cytology. This review aims to provide a comprehensive review of the drawbacks of endometrial cytopathology, particularly in terms of endometrial cancer diagnosis and molecular testing.

Assessing the role of Chemokine (C-C motif) ligand 14 in AKI: a European consensus meeting.

BACKGROUND: Urinary Chemokine (C-C motif) ligand 14 (CCL14) is a biomarker associated with persistent severe acute kidney injury (AKI). There is limited data to support the implementation of this AKI biomarker to guide therapeutic actions. METHODS: Sixteen AKI experts with clinical CCL14 experience participated in a Delphi-based method to reach consensus on when and how to potentially use CCL14. Consensus was defined as ≥ 80% agreement (participants answered with 'Yes', or three to four points on a five-point Likert Scale). RESULTS: Key consensus areas for CCL14 test implementation were: identifying challenges and mitigations, developing a comprehensive protocol and pairing it with a treatment plan, and defining the target population. The majority agreed that CCL14 results can help to prioritize AKI management decisions. CCL14 levels above the high cutoff (> 13 ng/mL) significantly changed the level of concern for modifying the AKI treatment plan (p < 0.001). The highest level of concern to modify the treatment plan was for discussions on renal replacement therapy (RRT) initiation for CCL14 levels > 13 ng/mL. The level of concern for discussion on RRT initiation between High and Low, and between Medium and Low CCL14 levels, showed significant differences. CONCLUSION: Real world urinary CCL14 use appears to provide improved care options to patients at risk for persistent severe AKI. Experts believe there is a role for CCL14 in AKI management and it may potentially reduce AKI-disease burden. There is, however, an urgent need for evidence on treatment decisions and adjustments based on CCL14 results.

Biomarker Testing Trends in Patients With Metastatic Colorectal Cancer Who Live in Rural Areas and Urban Clusters in the US.

BACKGROUND: There is a paucity of data on biomarker testing rates in rural populations with metastatic colorectal cancer (mCRC). To assess biomarker testing practices, oncologists in rural areas and urban clusters in the US were surveyed. MATERIALS AND METHODS: A web-based survey was administered to oncologists spending ≥40% of their time practicing in rural areas or urban clusters and who had treated ≥2 patients with stage IV mCRC in the prior month. RESULTS: Ninety-nine oncologists completed the quantitative survey and 17 the qualitative interview. Among respondents, 97% reported ordering biomarker tests. Oncologists reported testing for KRAS, NRAS, BRAF, HER2, and mismatch repair deficiency/microsatellite instability in 72%, 65%, 63%, 56%, and 66% of patients with metastatic disease, respectively. Forty-one percent reported performing reflex testing. The most cited testing barriers were lack of insurance coverage, insufficient tissue samples, and long turnaround times. CONCLUSION: Further assessment of rural testing practices is needed.

Optimizing molecular testing of lung cancer needle biopsy specimens: potential solutions from an interdisciplinary qualitative study.

BACKGROUND: Molecular testing can detect actionable genomic alterations and tumor cell surface proteins in patients with non-small cell lung cancer (NSCLC). However, utilization remains suboptimal, representing missed treatment opportunities. This study aimed to identify challenges and potential solutions to obtaining percutaneous lung needle biopsy specimens for successful molecular testing in patients with advanced NSCLC. METHODS: This interdisciplinary qualitative study included ten radiologists and four pathologists from academic and community settings across the United States who routinely perform and analyze percutaneous lung needle biopsies. Participants underwent semi-structured one-on-one interviews (Phase 1). Interview questionnaires were constructed based on a literature review of key lines of inquiry and conducted by professional market researchers using the theoretical domains framework. Primary barriers to molecular testing were identified using thematic analysis. Subsequently, multidisciplinary focus groups were convened to identify potential solutions (Phase 2). RESULTS: Four themes emerged as barriers to molecular testing and were matched to the clinical workflow: (1) biopsy request, (2) biopsy procedure, (3) specimen analysis, and (4) communication. The nineteen potential solutions included adding a "checkbox" to indicate molecular testing in the biopsy request, leveraging pre-procedural imaging to guide biopsies, conserving tissue through appropriate allocation strategies and next generation sequencing panels instead of sequential single-gene assays, instituting reflex-molecular testing upon NSCLC diagnosis, tracking and communicating biopsy outcomes at multidisciplinary tumor boards, and improving integration of radiologists and pathologists into oncology care teams. CONCLUSIONS: Potential solutions exist to increase successful molecular testing of lung needle biopsy specimens in patients with advanced NSCLC.

Challenges in diagnosis and biomarker testing for RET-altered lung and thyroid cancer care: an international mixed-method study.

BACKGROUND: The introduction of new targeted therapies for RET-altered lung and thyroid cancers (LC/TC) has impacted pathologists' practice by making genomic testing more relevant. Variations in health systems and treatment access result in distinct clinical challenges and barriers. This study aimed to assess practice gaps and challenges experienced by pathologists involved in the diagnosis of RET-altered LC/TC, including biomarker testing, to inform educational solutions. METHODS: Pathologists in Germany, Japan, the UK, and US participated in this ethics-approved mixed-methods study, which included interviews and surveys (data collected January-March 2020). Qualitative data was thematically analysed, quantitative data was analysed with chi-square and Kruskal-Wallis H-tests, and both were triangulated. RESULTS: A total of 107 pathologists took part in this study. Knowledge gaps were reported regarding genomic testing for LC/TC in Japan (79/60%), the UK (73/66%), and the US (53/30%). Skill gaps were reported when selecting genomic biomarker tests to diagnose TC in Japan (79%), the UK (73%) and US (57%) and when performing specific biomarker tests, especially in Japan (82% for RET) and in the UK (75% for RET). Japanese participants (80%) reported uncertainty about what information to share with the multidisciplinary team to ensure optimal patient-centered care. At the time of data collection, pathologists in Japan faced access barriers to using RET biomarker tests: only 28% agreed that there are relevant RET genomic biomarker tests available in Japan, versus 67% to 90% in other countries. CONCLUSIONS: This study identified areas where pathologists need additional continuing professional development opportunities to enhance their competencies and better support delivery of care to patients with RET-altered lung or thyroid tumours. Addressing identified gaps and improving competencies of pathologists in this field should be emphasised in continuing medical education curricula and through quality improvement initiatives. Strategies deployed on an institutional and health system level should aim to improve interprofessional communication and genetic biomarker testing expertise.

State legislative trends related to biomarker testing.

Comprehensive biomarker testing has become the standard of care for informing the choice of the most appropriate targeted therapy for many patients with advanced cancer. Despite evidence demonstrating the need for comprehensive biomarker testing to enable the selection of appropriate targeted therapies and immunotherapy, the incorporation of biomarker testing into clinical practice lags behind recommendations in National Comprehensive Cancer Network guidelines. Coverage policy differences across insurance health plans have limited the accessibility of comprehensive biomarker testing largely to patients whose insurance covers the recommended testing or those who can pay for the testing, and this has contributed to health disparities. Furthermore, even when insurance coverage exists for recommended biomarker testing, patients may incur burdensome out-of-pocket costs depending on their insurance plan benefits, which may also create barriers to testing. Prior authorization for biomarker testing for some patients can add an administrative burden and may delay testing and thus treatment if it is not done in a timely manner. Recently, three states (Illinois, Louisiana, and California) passed laws designed to improve access to biomarker testing at the state level. However, there is variability among these laws in terms of the population affected, the stage of cancer, and whether the coverage of testing is mandated, or the legislation addresses only prior authorization. Advocacy efforts by patient advocates, health care professionals, and professional societies are imperative at the state level to further improve coverage for and access to appropriate biomarker testing.

An Expert, Multidisciplinary Perspective on Best Practices in Biomarker Testing in Intrahepatic Cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (iCCA) is a rare and aggressive malignancy that arises from the intrahepatic biliary tree and is associated with a poor prognosis. Until recently, the treatment landscape of advanced/metastatic iCCA has been limited primarily to chemotherapy. In recent years, the advent of biomarker testing has identified actionable genetic alterations in 40%-50% of patients with iCCA, heralding an era of precision medicine for these patients. Biomarker testing using next-generation sequencing (NGS) has since become increasingly relevant in iCCA; however, several challenges and gaps in standard image-guided liver biopsy and processing have been identified. These include variability in tissue acquisition relating to the imaging modality used for biopsy guidance, the biopsy method used, number of passes, needle choice, specimen preparation methods, the desmoplastic nature of the tumor, as well as the lack of communication among the multidisciplinary team. Recognizing these challenges and the lack of evidence-based guidelines for biomarker testing in iCCA, a multidisciplinary team of experts including interventional oncologists, a gastroenterologist, medical oncologists, and pathologists suggest best practices for optimizing tissue collection and biomarker testing in iCCA.

Barriers to mutational testing in patients with gastrointestinal stromal tumors (GIST) - a survey of life raft group members.

BACKGROUND: Due to the low mutational testing rate in patients with Gastrointestinal Stromal Tumors (GIST), The Life Raft Group (LRG), a non-profit organization that provides support, advocacy and conducts research for patients with GIST, analyzed various factors that may have an impact on patients' ability to receive mutational testing. METHODS: A survey about mutational testing for patients with GIST or their caregivers, was conducted in June 2020. The survey, sent to 1004 GIST patients and caregivers through email, was promoted through social media with instructions to contact the LRG to participate. The survey was designed by the LRG Patient Registry Department. Members of the LRG, regardless of Patient Registry status, were eligible to participate. RESULTS: A total of 295 patients/caregivers participated in this study (response rate: 29.4%). The percentage of patients who indicated they had received mutational testing was much higher in this survey (80%) than in the general GIST community (26.7%). Several reasons were cited for having a test, including: "My doctor ordered/suggested that I have it done" (54%); "The Life Raft Group advised/suggested I have it done" (25%); "I asked my doctor to have it done" (22%); "I had it done as part of a clinical trial" (5%); "I am not sure" (3%) and "Other" (14%). Mutational testing resulted in a treatment change in 25% of cases. Patients were able to select more than one option when completing this question resulting in a percentage greater than 100. CONCLUSIONS: The LRG membership is voluntary and proactive; patients who join are more likely to participate in surveys and mutational testing, as well as more likely to have a GIST specialist. Mutational testing can influence understanding of a patient's GIST and the treatment best suited to each case. These are extremely important findings, as it helps ensure that patients are on the proper treatment, which should lead to better outcomes.

Disparities in Lung Cancer Treatment.

PURPOSE OF REVIEW: Despite an overall reduction in lung cancer incidence and mortality rates worldwide, Blacks still have higher mortality rates compared to Whites. There are many factors that contribute to this difference. This review seeks to highlight racial disparities in treatment and the possible reasons for these disparities. RECENT FINDINGS: Factors attributing to racial disparities in lung cancer treatment include social determinants of health, differences in the administration of guideline-concordant therapy as well as molecular testing that is essential for most NSCLC patients. One way to circumvent disparities in lung cancer survivorship is to ensure equal representation of race in research at all levels that will provide insight on interventions that will address social determinants of health, differences in treatment patterns, molecular testing, and clinical trial involvement.

Diagnostic and economic value of biomarker testing for targetable mutations in non-small-cell lung cancer: a literature review.

We aimed to assess the diagnostic and economic value of next-generation sequencing (NGS) versus single-gene testing, and of liquid biopsy (LBx) versus tissue biopsy (TBx) in non-small-cell lung cancer biomarker testing through literature review. Embase and MEDLINE were searched to identify relevant studies (n = 43) from 2015 to 2020 in adults with advanced non-small-cell lung cancer. For NGS versus single-gene testing, concordance was 70-99% and sensitivity was 86-100%. For LBx versus TBx, specificity was 43-100% and sensitivity was ≥60%. Turnaround times were longer for NGS versus single-gene testing (but not vs sequential testing) and faster for LBx versus TBx. NGS was cost-effective, and LBx reduced US per-patient costs. NGS versus single-gene testing and LBx versus TBx were concordant. NGS and LBx may be cost-effective for initial screening.

Plain language summary Patients with lung cancer with specific genetic mutations can benefit from medications that are specific to those mutations, known as targetable mutations. There are many methods to test for specific genetic mutations in patients with lung cancer. To detect genetic mutations, doctors can test the blood or urine, or they can test biopsy tissue; a small piece of the tumor removed from the lung. These tests can either look for mutations in one specific gene at a time, or they can use technology that reads the entire DNA sequence to observe multiple genes at once. In this review, we examined scientific reports to answer important questions about using genetic testing to find targetable mutations in patients with lung cancer. How accurate are different genetic tests? How fast can doctors get results from different genetic tests? How much do different genetic tests cost? We found that reading the entire DNA sequence was as accurate as testing one specific gene. Reading the entire DNA sequence takes more time than testing one specific gene, but it might reduce overall costs. Testing blood or urine was not as accurate as testing tissue, but it took less time for doctors to receive genetic test results and reduced costs.

Testing methods to diagnose TRK fusion cancer - a plain language summary and patient perspective.

WHAT IS THIS SUMMARY ABOUT?: This is a plain language summary of a 2022 study published in Cancer Genetics. This study describes the different tests used to detect a rare type of cancer called TRK (tropomyosin receptor kinase) fusion cancer in people taking part in three clinical trials testing the medication larotrectinib. Larotrectinib targets TRK fusion proteins, abnormal proteins that result from abnormal NTRK (neurotrophic tyrosine receptor kinase) gene fusions. People who were shown to have solid tumors containing TRK fusion proteins were able to participate in clinical trials that evaluated larotrectinib. WHAT WERE THE RESULTS?: Different testing methods were used to identify participants with TRK fusion cancer. Which test was used depended on different factors such as how commonly NTRK gene fusions are found in a specific cancer type, and the cost and accessibility of the test. Participants with different types of cancer were included in the study, which allowed researchers to identify which TRK fusion proteins were found across various types of tumor. WHAT DO THE RESULTS MEAN?: The results of this study provide a guidance for healthcare professionals on the methods used for testing to identify patients that have TRK fusion cancer. By characterizing the types of testing done across cancer types, patients and their caregivers can gain an understanding of the importance of testing. This plain language summary also includes insights and perspectives from a person affected by TRK fusion cancer, and from patient advocates. Clinical Trial Registration: NCT02122913 (ClinicalTrials.gov) Clinical Trial Registration: NCT02637687 (ClinicalTrials.gov) Clinical Trial Registration: NCT02576431 (ClinicalTrials.gov).

Trends in real-world biomarker testing and overall survival in US patients with advanced non-small-cell lung cancer.

Background: Trends/outcomes associated with National Comprehensive Cancer Network (NCCN)-recommended biomarker testing to guide advanced non-small-cell lung cancer (aNSCLC) treatment were assessed. Methods: Patients initiating first-line aNSCLC treatment were included using a nationwide electronic health record-derived database (1/1/2015-10/31/2021). Trends in pre-first-line biomarker testing (PD-L1, major genomic aberrations), factors associated with testing and associations between testing and outcomes were assessed. Results: PD-L1/genomic aberration testing rates increased from 33% (2016) to 81% (2018), then plateaued. Certain clinical and demographic factors were associated with a greater likelihood of PD-L1 testing. Patients tested for PD-L1 or genomic aberrations had longer overall survival (OS). Conclusion: Biomarker testing may be associated with improved OS in aNSCLC, though not all patients had equal access to testing.

Molecular diagnostics play a critical role in precision medicine. Treatment guidelines from the National Comprehensive Cancer Network (NCCN) recommend that patients newly diagnosed with advanced non-small-cell lung cancer (aNSCLC) undergo molecular testing for PD-L1 and genomic aberrations to guide treatment choices. Based on the results of such biomarker testing, physicians can select optimal treatments for individual patients. The aim of this study was to describe the latest trends and disparities in real-world biomarker testing with a focus on PD-L1 and to explore the impact of biomarker testing on outcomes in first-line treatment of aNSCLC in the United States. Patients initiating first-line aNSCLC treatment were identified in the Flatiron Health database (1/1/2015­10/31/2021; N = 30,631). Annual trends in pre-first-line biomarker testing (PD-L1, major genomic aberrations), demographic and clinical factors associated with PD-L1 testing, and associations between PD-L1 and/or ≥1 genomic aberration testing and outcomes (e.g., overall survival [OS], time-to-next treatment [TTNT]) were assessed. Biomarker testing in patients receiving first-line treatment for aNSCLC increased between 2015 and 2017 and plateaued between 2018 and 2021. By 2021, approximately 20% of patients did not receive PD-L1 testing before first-line treatment and not all patients had equal access to testing. Both PD-L1 and genomic aberration testing were associated with improved OS and TTNT. This is likely due to enhanced treatment decisions leading to optimal treatment selection. Future research is warranted to understand interventions to improve biomarker testing and reduce disparities between different patient populations to improve treatment outcomes.

Glycan biomarkers of autoimmunity and bile acid-associated alterations of the human glycome: Primary biliary cirrhosis and primary sclerosing cholangitis-specific glycans.

We have recently introduced multiple reaction monitoring (MRM) mass spectrometry as a novel tool for glycan biomarker research and discovery. Herein, we employ this technique to characterize the site-specific glycan alterations associated with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Glycopeptides associated with disease severity were also identified. Multinomial regression modelling was employed to construct and validate multi-analyte diagnostic models capable of accurately distinguishing PBC, PSC, and healthy controls from one another (AUC = 0.93 ± 0.03). Finally, to investigate how disease-relevant environmental factors can influence glycosylation, we characterized the ability of bile acids known to be differentially expressed in PBC to alter glycosylation. We hypothesize that this could be a mechanism by which altered self-antigens are generated and become targets for immune attack. This work demonstrates the utility of the MRM method to identify diagnostic site-specific glycan classifiers capable of distinguishing even related autoimmune diseases from one another.

ctDNA from body fluids is an adequate source for EGFR biomarker testing in advanced lung adenocarcinoma.

OBJECTIVES: Epidermal growth factor receptor (EGFR) biomarker testing using blood-based liquid biopsies remains challenging due to the low concentration of circulating tumor DNA (ctDNA) in certain plasma samples. The aim of this study is to evaluate the usefulness for EGFR biomarker testing of ctDNA from pleural effusions, cerebrospinal fluids, ascites and pericardial effusions obtained during the clinical management of lung adenocarcinoma patients. METHODS: For comparison purposes, 23 paired plasma and body fluid samples were collected from 17 patients with EGFR-positive lung adenocarcinoma. After circulating free DNA (cfDNA) isolation, samples were evaluated for the initial EGFR-sensitizing mutation and the p.T790M resistance mutation by array-based digital PCR (dPCR). RESULTS: Body fluids had more cfDNA than plasma samples (1.90 vs. 0.36 ng/µL; p=0.0130), and more samples tested positive for EGFR mutations (21 vs. 16 samples), with a total of 28 vs. 22 variants detected. Furthermore, mutant allele frequencies (MAFs) observed in body fluids were significantly higher than those assessed in the paired plasma samples for EGFR-sensitizing mutations (median MAFs = 15.8 vs. 0.8%; p=0.0004) as well as for the p.T790M resistance mutation (median MAFs = 8.69 vs. 0.16%; p=0.0390). Importantly, two patients who had progressed on first-generation EGFR-tyrosine kinase inhibitors with a dubious result for p.T790M plasma (MAFs = 0.11%) had an indisputably positive result in their respective body fluid samples (MAFs = 10.25 and 9.66%). CONCLUSIONS: ctDNA derived from body fluids is an informative source for EGFR biomarker testing, with greater sensitivity than plasma samples.

Molecular profiling and characteristics of non-small-cell lung cancer patients in Georgia.

Aims: In patients with advanced non-small-cell lung cancer, the correlation between histopathology, smoking status, driver oncogene mutations and PD-L1 overexpression were investigated. Patients and methods: A total of 202 patients were identified. Research was done in Georgia. Results: EGFR mutations were detected in 6% of the tested cases (12/187) and five out of 12 EGFR+ cases had histology consistent with squamous cell carcinoma. No statistically significant correlation was observed between PD-L1 expression, smoking status and clinicopathological characteristics. However, the correlation between smoking status and histology was statistically significant (p = 0.0264), as never-smokers had a higher incidence of adenocarcinoma histology. Conclusion: The study showed a small percentage of EGFR mutations associated with adenocarcinoma histology and revealed a solid existence of this mutation in squamous cell carcinoma histology. A higher incidence of adenocarcinoma histology was observed in never-smokers.

Endobronchial ultrasound-guided transbronchial needle aspiration in patients with previously treated lung cancer.

PURPOSE: The sampling and accurate diagnosis of lymph nodes during the clinical history of lung cancer are essential for selecting the appropriate treatment strategies. This study aims to evaluate the feasibility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with previously treated lung cancer. METHODS: Patients who underwent EBUS-TBNA after treatment for lung cancer were retrospectively reviewed. We classified the patients into two groups; Group 1 (G1): Indicated to have a recurrence of new lesions after radical surgery or chemo/radiotherapy with a curative intent; and Group 2 (G2): Indicated to have residual tumor cells after undergoing primary treatment for chemo/radiotherapy or re-staging after induction therapy prior to surgery. RESULTS: Seventy previously treated lung cancer cases (G1, n = 52; G2, n = 18) were enrolled. Thirty-two cases (61.5%) had recurrent disease in G1, and 9 cases (50.0%) had nodal metastasis in G2. The diagnostic accuracy was 95.2% in G1 and 88.9% in G2. Twenty-four cases were examined for epidermal growth factor receptor (EGFR) mutations, and 9 (37.5%) cases had mutations, including two cases with a T790M mutation. Furthermore, in one case, a re-biopsy revealed that the initial adenocarcinoma had transformed into small cell lung cancer. CONCLUSION: Performing EBUS-TBNA during lung cancer treatment showed a high diagnostic yield. Samples obtained by EBUS-TBNA were helpful in determining when to perform repeat biomarker testing as well as for making pathological re-evaluations.

Next-generation sequencing for tumor mutation quantification using liquid biopsies.

Background Non-small cell lung cancer (NSCLC) patients benefit from targeted therapies both in first- and second-line treatment. Nevertheless, molecular profiling of lung cancer tumors after first disease progression is seldom performed. The analysis of circulating tumor DNA (ctDNA) enables not only non-invasive biomarker testing but also monitoring tumor response to treatment. Digital PCR (dPCR), although a robust approach, only enables the analysis of a limited number of mutations. Next-generation sequencing (NGS), on the other hand, enables the analysis of significantly greater numbers of mutations. Methods A total of 54 circulating free DNA (cfDNA) samples from 52 NSCLC patients and two healthy donors were analyzed by NGS using the Oncomine™ Lung cfDNA Assay kit and dPCR. Results Lin's concordance correlation coefficient and Pearson's correlation coefficient between mutant allele frequencies (MAFs) assessed by NGS and dPCR revealed a positive and linear relationship between the two data sets (ρc = 0.986; 95% confidence interval [CI] = 0.975-0.991; r = 0.987; p < 0.0001, respectively), indicating an excellent concordance between both measurements. Similarly, the agreement between NGS and dPCR for the detection of the resistance mutation p.T790M was almost perfect (K = 0.81; 95% CI = 0.62-0.99), with an excellent correlation in terms of MAFs (ρc = 0.991; 95% CI = 0.981-0.992 and Pearson's r = 0.998; p < 0.0001). Importantly, cfDNA sequencing was successful using as low as 10 ng cfDNA input. Conclusions MAFs assessed by NGS were highly correlated with MAFs assessed by dPCR, demonstrating that NGS is a robust technique for ctDNA quantification using clinical samples, thereby allowing for dynamic genomic surveillance in the era of precision medicine.