Combined plasma and tissue genotyping of EGFR T790M benefits NSCLC patients: a real-world clinical example

'Plasma first' approach for detecting epidermal growth factor receptor mutation in advanced non-small cell lung carcinoma

INTRODUCTION

The treatment approach for recently diagnosed advanced non-small cell lung cancer (NSCLC) with EGFR mutations primarily relies on confirming the tissue diagnosis as non-squamous NSCLC. This routine clinical practice of tissue diagnosis imposes several barriers and delays in turnaround time (TAT) for biomarker testing, significantly delaying the time to treatment. The objective of this study is to investigate the 'plasma first' approach for detection of EGFR mutation in advanced stage treatment naïve NSCLC patients.

METHODS

We prospectively collected blood samples of treatment naïve patients with clinical and radiological suspicion of advanced stage NSCLC prior to obtaining tissue biopsy. Plasma cfDNA was tested for EGFR mutation using two different methods. We compared the sensitivity and TAT of liquid biopsy with tissue biopsy.

RESULTS

In total, we analyzed plasma cell-free DNA (cfDNA) of 236 patients suspected of having advanced NSCLC for EGFR mutations. We observed a notably shorter turnaround time (TAT) of 3 days, which was significantly quicker compared to the 12-day TAT for tissue biopsy (p < 0.05). The ddPCR method had a sensitivity of 82.8%, which was higher than 66.34% sensitivity of ARMS-PCR. The current study also highlights that there is no significant difference in the clinical outcome of the patients whether treated based on liquid biopsy only or tissue biopsy (median progression-free survival of 11.56 vs. 11.9 months; p = 0.94).

CONCLUSIONS

Utilizing a 'plasma first' strategy, given its shorter turnaround time, strong positive concordance and comparable outcomes to tissue biopsy, emerges as a highly specific and reliable method for detecting EGFR mutations in advanced-stage NSCLC.

Repeat biopsy versus initial biopsy in terms of complication risk factors and clinical outcomes for patients with non-small cell lung cancer: a comparative study of 113 CT-guided needle biopsy of lung lesions

Objectives

The safety and feasibility of repeat biopsy after systemic treatment for non-small cell lung cancer have received extensive attention in recent years. The purpose of this research was to compare complication rates between initial biopsy and rebiopsy in non-small cell lung cancer patients with progressive disease and to assess complication risk factors and clinical results after rebiopsy.

Methods

The study included 113 patients initially diagnosed with non-small cell lung cancer who underwent lung biopsy at initial biopsy and rebiopsy after progression while on epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and/or chemotherapy from January 2018 to December 2021. We compared the incidence of complications between the initial biopsy and rebiopsy and analyzed the predictors factors that influenced complications in patients who underwent rebiopsy.

Results

The successful rate of rebiopsy was 88.5% (100/113). With the exception of two cases where lung adenocarcinoma changed into small cell lung cancer with gefitinib treatment, 98 individuals retained their initial pathological type. The secondary EGFR T790M mutation accounts for 55.6% of acquired resistance. The total number of patients with complications in initial biopsy was 25 (22.1%) and 37 (32.7%) in the rebiopsy. The incidence of pulmonary hemorrhage increased from 7.1% at the initial biopsy to 10.6% at rebiopsy, while the incidence of pneumothorax increased from 14.2% to 20.4%. Compared with the initial biopsy, the incidence of overall complications, parenchymal hemorrhage, and pneumothorax increased by 10.6%, 3.5%, and 6.2%, respectively. In all four evaluations (pneumorrhagia, pneumothorax, pleural reaction, and overall complication), there were no significant differences between the rebiopsy and initial biopsy (all p > 0.05). The multivariate logistic regression analysis suggested that male sex (odds ratio [OR] = 5.064, p = 0.001), tumor size ≤ 2 cm (OR = 3.367, p = 0.013), EGFR-TKIs with chemotherapy (OR = 3.633, p =0.023), and transfissural approach (OR = 7.583, p = 0.026) were independent risk factors for overall complication after rebiopsy.

Conclusion

Compared with the initial biopsy, the complication rates displayed a slight, but not significant, elevation in rebiopsy. Male sex, tumor size ≤ 2 cm, transfissural approach, and EGFR-TKIs combined with chemotherapy were independent risk factors for rebiopsy complications.

Genetic mutation profiling reveals biomarkers for targeted therapy efficacy and prognosis in non-small cell lung cancer

Introduction

The genetic heterogeneity of non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations may affect clinical responses and outcomes to EGFR tyrosine kinase inhibitors (EGFR-TKIs). This study aims to investigate the genomic factors that influence the efficacy and clinical outcomes of first-line, second-line and third-line treatments in NSCLC and explore the heterogeneity of resistance mechanisms.

Materials and methods

This real-world study comprised 65 patients with EGFR mutant NSCLC. Molecular alterations were detected using a customized DNA panel before and after administering targeted therapy. The efficacy and prognosis of each treatment line were evaluated.

Results

In first-generation EGFR-TKIs treatment, gefitinib showed favorable efficacy compared to icotinib and erlotinib, particularly in patients with EGFR L858R mutations. The resistance mechanisms to first-generation EGFR-TKIs varied among different EGFR mutation cohorts and different first-generation EGFR-TKIs. In second-line EGFR-TKIs treatment, EPH receptor A3 (EPHA3), IKAROS family zinc finger 1 (IKZF1), p21 (RAC1) activated kinase 5 (PAK5), DNA polymerase epsilon, catalytic subunit (POLE), RAD21 cohesin complex component (RAD21) and RNA binding motif protein 10 (RBM10) mutations were markedly associated with poorer progression-free survival (PFS). Notably, EPHA3, IKZF1 and RBM10 were identified as independent predictors of PFS. The mechanisms of osimertinib resistance exhibited heterogeneity, with a higher proportion of non-EGFR-dependent resistant mutations. In third-line treatments, the combination of osimertinib and anlotinib demonstrated superior efficacy compared to other regimens. Glutamate ionotropic receptor NMDA type subunit 2A (GRIN2A) mutation was an independent risk indicator of shorter OS following third-line treatments.

Conclusions

Comprehending the tumor evolution in NSCLC is advantageous for assessing the efficacy and prognosis at each stage of treatment, providing valuable insights to guide personalized treatment decisions for patients.

Real-world analysis of the prognostic value of EGFR mutation detection in plasma ctDNA from patients with advanced non-small cell lung cancer

BACKGROUND

The plasma sample has emerged as a promising surrogate sample for EGFR mutation detection in advanced non-small cell lung cancer (NSCLC). In clinical practice, whether EGFR variants in baseline plasma ctDNA of advanced NSCLC can predict prognosis in addition to guiding targeted therapy remains to be further explored.

MATERIAL AND METHODS

In total, 315 NSCLC patients were retrospectively enrolled. EGFR mutation data from tissue detected by ARMS-PCR and paired plasma samples within 1 month of admission detected by SuperARMS or ARMS-PCR were collected. The correlation between baseline plasma ctDNA EGFR mutation status and survival was compared.

RESULTS

EGFR mutation detection rates in tumor samples and plasma samples were 65.1% (205/315) and 43.8% (138/315). Referred to tissue results, the consistent rate of test ctDNA EGFR alteration by SuperARMS was higher than that detected by ARMS (79.5% vs. 69.0%, p = 0.04), either in stage I-IIIA patients (85.7% vs. 50.0%, p = 0.4) or stage IIIB-IV patients (79.1% vs. 69.4%, p = 0.04). Patients' treatment status and pathological subtype were the two factors that affected plasma ctDNA EGFR alteration detection accuracy. The concordance in non-adenocarcinoma patients was obviously higher than that in adenocarcinoma (p = 0.02), and the concordance in treatment naïve patients was significantly higher than that in relapse patients (p = 0.047). In treatment naïve patients, the median PFS (mPFS) in plasma ctDNA EGFR-positive patients was shorter than that in plasma ctDNA EGFR negative patients (7.0 vs. 10.0 months, p = 0.01). In relapsed patients, the mPFS in plasma ctDNA EGFR-positive patients was 9.0 months versus 11.0 months in plasma ctDNA EGFR negative patients (p = 0.1).

CONCLUSIONS

A plasma sample could be an alternative for a molecular test when tissue samples was unavailable. The SuperARMS-PCR detection method has high sensitivity in real-world clinical practice. Furthermore, in patients with stage IIIB-IV, baseline plasma ctDNA EGFR mutation positivity not only guides targeted therapy but also predicts a worse prognosis.

Liquid biopsy: early and accurate diagnosis of brain tumor

Noninvasive examination is an emerging area in the field of neuro-oncology. Liquid biopsy captures the landscape of genomic alterations of brain tumors and revolutionizes the traditional diagnosis approaches. Rapidly changing sequencing technologies and more affordable prices put the screws on more application of liquid biopsy in clinical settings. In the past few years, extensive application of liquid biopsy has been seen throughout the whole diagnosis and treatment process of brain tumors, including early and accurate detection, characterization and dynamic monitoring. Here, we summarized and compared the most advanced techniques and target molecules or macrostructures related to brain tumor liquid biopsy. We further reviewed and emphasized recent progression in different clinical settings for brain tumors in blood and CSF. The preferred protocol, potential novel biomarkers and future development are discussed in the last part.

Clinical Practice Guidelines for Pre-Analytical Procedures of Plasma Epidermal Growth Factor Receptor Variant Testing

Standardization of cell-free DNA (cfDNA) testing processes is necessary to obtain clinically reliable results. The pre-analytical phase of cfDNA testing greatly influences the results because of the low proportion and stability of circulating tumor DNA (ctDNA). In this review, we provide evidence-based clinical practice guidelines for pre-analytical phase procedures of plasma epidermal growth factor receptor gene (EGFR) variant testing. Specific recommendations for pre-analytical procedures were proposed based on evidence from the literature and our experimental data. Standardization of pre-analytical procedures can improve the analytical performance of cfDNA testing.

Liquid Biopsy for EGFR Mutation Analysis in Advanced Non-Small-Cell Lung Cancer Patients: Thoughts Drawn from a Real-Life Experience

Background: Liquid biopsy analysis for EGFR detection in cell-free DNA (cfDNA) from NSCLC patients has become routine. The aim of this study was to explore its applicability in clinical practice. Methods: We collected data of EGFR-mutated NSCLC patients with liquid biopsy analysis. Data included test timing, concomitant tissue re-biopsy, therapy change, histology, stage, smoking habits, gender and age. All analyses were performed via a real-time PCR method to analyze EGFR mutations at exons 18, 19, 20 and 21. Variant allele frequency was performed for patients with available sequential EGFR mutation analysis in cfDNA. Overall survival was analyzed through the Kaplan–Meier method. We designed flow charts to show the real-life application of liquid biopsy. Results: We found that liquid biopsy is used in treatment-naïve patients as an alternative to EGFR detection in tumor tissue, and in patients with positive or negative EGFR from tumor biopsy. The majority of liquid biopsy analyses were performed in NSCLC patients who were disease progressive during TKI therapy. The presence of EGFR mutation in cfDNA was associated with a worse prognosis. In two patients, VAF of EGFR mutations in cfDNA was concordant with tumor volume changes. Conclusion: These findings suggest that liquid biopsy for EGFR detection can continue to be useful.

Tissue Adequacy and Safety of Percutaneous Transthoracic Needle Biopsy for Molecular Analysis in Non-Small Cell Lung Cancer: A Systematic Review and Meta-analysis

Objective

We conducted a systematic review and meta-analysis of the tissue adequacy and complication rates of percutaneous transthoracic needle biopsy (PTNB) for molecular analysis in patients with non-small cell lung cancer (NSCLC).

Materials and Methods

We performed a literature search of the OVID-MEDLINE and Embase databases to identify original studies on the tissue adequacy and complication rates of PTNB for molecular analysis in patients with NSCLC published between January 2005 and January 2020. Inverse variance and random-effects models were used to evaluate and acquire meta-analytic estimates of the outcomes. To explore heterogeneity across the studies, univariable and multivariable meta-regression analyses were performed.

Results

A total of 21 studies with 2232 biopsies (initial biopsy, 8 studies; rebiopsy after therapy, 13 studies) were included. The pooled rates of tissue adequacy and complications were 89.3% (95% confidence interval [CI]: 85.6%–92.6%; I² = 0.81) and 17.3% (95% CI: 12.1%–23.1%; I² = 0.89), respectively. These rates were 93.5% and 22.2% for the initial biopsies and 86.2% and 16.8% for the rebiopsies, respectively. Severe complications, including pneumothorax requiring chest tube placement and massive hemoptysis, occurred in 0.7% of the cases (95% CI: 0%–2.2%; I² = 0.67). Multivariable meta-regression analysis showed that the tissue adequacy rate was not significantly lower in studies on rebiopsies (p = 0.058). The complication rate was significantly higher in studies that preferentially included older adults (p = 0.001).

Conclusion

PTNB demonstrated an average tissue adequacy rate of 89.3% for molecular analysis in patients with NSCLC, with a complication rate of 17.3%. PTNB is a generally safe and effective diagnostic procedure for obtaining tissue samples for molecular analysis in NSCLC. Rebiopsy may be performed actively with an acceptable risk of complications if clinically required.

Content of circulating tumor DNA depends on the tumor type and the dynamics of tumor size, but is not influenced significantly by physical exercise, time of the day or recent meal

PURPOSE

This study aimed to investigate factors, which influence the content of circulating tumor DNA (ctDNA).

METHODS

398 serial plasma samples were collected within 1-7 consecutive days from patients with EGFR-mutated lung cancer (n = 13), RAS/RAF-mutated colorectal cancer (n = 54) and BRAF-mutated melanoma (n = 17), who presented with measurable tumor disease. The amount of ctDNA was determined by ddPCR.

RESULTS

Among 82 patients, who donated 2-6 serial plasma samples, 42 subjects were classified as ctDNA-positive; only 22% cases were mutation-positive across all consecutive tests, while 24/82 (29%) patients showed presence of mutated ctDNA in some but not all blood draws. Subjects with progressing tumors had higher probability of being detected ctDNA-positive as compared to patients, who responded to therapy or had stable disease (39/55 (71%) vs. 4/24 (17%); p = 0.0001). Our study failed to reveal the impact of the time of the day, recent meal or prior physical exercise on the results of ctDNA testing.

CONCLUSIONS

Presence of ctDNA in plasma is particularly characteristic for patients, who experience clinical progression of tumor disease. Consecutive plasma tests may occasionally provide discordant data; thus, the repetition of analysis may be advised in certain cases in order to ensure the validity of negative ctDNA result.

The usefulness of microRNA in urine and saliva as a biomarker of gastroenterological cancer

MicroRNA (miR) is a type of short non-coding RNA comprising 21-25 nucleotides. While it has been researched widely, its relationship with cancer was clarified recently and it was found to play a significant role in the development and progression of cancer. Furthermore, miR can remain stable for relatively long periods in the blood by being present in exosomes (extracellular microvesicles) or by forming a complex with the Ago2 protein, which gives rise to cancer-specific miR. It is known that miR can indicate the presence and extent of cancer progression. Several reports have proved that miR in urine and saliva is detected in urinary and oral cancer, respectively, and recent studies have also shown it to be present in cases of gastroenterological cancer, showing evidence of it being a biomarker for cancer. To gather further knowledge on this topic, this review aims to summarize the usefulness of urinary and salivary miR as a biomarker for gastroenterological cancer and discuss its existence, stability mechanism, and direction of future research. The findings will be relevant for physicians and oncologists who routinely treat patients with gastric cancers.