Comparison of sampling methods for next generation sequencing for patients with lung cancer

Usefulness of endoscopic ultrasound with bronchoscope-guided fine-needle aspiration for next-generation sequencing in patients with non-small cell lung cancer: A comparison with other bronchoscopic techniques

BACKGROUND

Next-generation sequencing (NGS) is essential in treating advanced lung cancer. However, the effectiveness of endoscopic ultrasound with bronchoscope-guided fine-needle aspiration (EUS-B-FNA) in NGS remains unclear. This study examined the usefulness of EUS-B-FNA in lung cancer NGS cases where EUS-B-FNA was performed for specimen submission in a nationwide genomic screening platform (LC-SCRUM-Asia) and compared specimens collected using other bronchoscopy methods (endobronchial ultrasound-guided transbronchial needle aspiration [EBUS-TBNA] and EBUS-guided transbronchial biopsy with a guide sheath [EBUS-GS-TBB]) during the same period.

METHODS

We retrospectively compared the NGS success rates of NGS, DNA and RNA yields for EUS-B-FNA, EBUS-TBNA, and EBUS-GS-TBB from the records of the patients recruited for the Lung Cancer Genomic Screening Project for Individualized Medicine (LC-SCRUM)-Asia.

RESULTS

Fifty-one patients were enrolled, and the NGS success rates were comparable for samples obtained by EUS-B-FNA, EBUS-TBNA, and EBUS-GS-TBB (100%, 90.9%, and 81.0%, respectively). Genetic alterations were detected in 73.7%, 90.9%, and 85.7% of patients, respectively, with druggable genetic alterations found in 31.6%, 72.7%, and 61.9% of patients, respectively. The DNA and RNA yields were significantly higher in EUS-B-FNA samples than in EBUS-GS-TBB samples (50.4 (interquartile range (IR): 15.45-72.35) ng/μl and 33.9 (IR: 9-76.8) ng/μl from EUS-B-FNA, and 3.3 (IR: 1.4-7.1) ng/μl and 15.1 (IR: 8.3-31.5) ng/μl from EBUS-GS-TBB, respectively, p < 0.05).

CONCLUSION

EUS-B-FNA emerges as a promising bronchoscopic method for obtaining adequate samples for NGS in advanced lung cancer cases.

Suitability of frozen cell pellets from cytology specimens for the Amoy 9-in-1 assay in patients with non-small cell lung cancer

BACKGROUND

The AmoyDx Pan lung cancer PCR panel (AmoyDx PLC panel) has been approved as a companion diagnostic tool for multiple anticancer agents in patients with non-small cell lung cancer (NSCLC). However, the suitability of cytology specimens as samples for the AmoyDx PLC panel remains unclear. We evaluated the performance of frozen cell pellets from cytology specimens (FCPs) in the Amoy 9-in-1 assay, a preapproval assay of the AmoyDx PLC panel.

METHODS

We retrospectively collected data of NSCLC patients enrolled in LC-SCRUM-Asia from the Shizuoka Cancer Center between September 2019 and May 2021.

RESULTS

A total of 49 cases submitted FCPs for evaluation of oncogenic driver alterations and were assessed using Amoy 9-in-1 and next-generation sequencing (NGS) assays. The success rates of DNA and RNA analyses using the Amoy 9-in-1 were both 100%, compared with 86% and 45%, respectively, using NGS assays. Oncogenic driver alterations were detected in 27 (55%) and 23 (47%) patients using Amoy 9-in-1 and NGS, respectively. No inconsistent results were observed among 19 cases in which both assays showed successful detection. In the remaining 30 cases, 10 had inconsistent results: nine oncogenic driver alterations (3 MET, 2 ALK, 2 ROS1, and 2 KRAS) were detectable only in Amoy 9-in-1, and one epidermal growth factor receptor (EGFR) mutation was detectable only in NGS.

CONCLUSION

FCPs can be successfully used in the AmoyDx PLC panel, with higher success rate compared with the NGS assay. The AmoyDx PLC panel may be an option in cases when insufficient tissue sample is available for the NGS assay.

Comparison of transbronchial biopsy techniques using needle and forceps biopsies in lung cancer for molecular diagnostics: a prospective, randomized crossover trial

Background

In lung cancer, molecular testing and next-generation sequencing (NGS) are needed to identify therapeutic targets and are increasingly being used in earlier stages of the disease. Despite its longstanding use, it remains unclear whether transbronchial needle aspiration (TBNA) of peripheral lung lesions provides as adequate material for genetic testing as transbronchial forceps biopsies (TBFBs). In this study, we aim to analyze the use of TBNA using median viable cell area (MVCA) as a surrogate parameter to analyze sample quality.

Methods

This prospective single-center study analyzed biopsy specimens or aspirates of patients who underwent bronchoscopy with transbronchial biopsy. Patients underwent bronchoscopy with TBFB and TBNA for suspected lung cancer in peripheral lung lesions. Patients were randomized 1:1 to receive either TBFB or TBNA as the first biopsy technique and then switched to the other. After routine workup, sample slides were digitally scanned, and MVCA was calculated by a pathologist blinded to the biopsy technique used. The primary endpoint was MVCA of TBNA versus TBFB. Secondary endpoints were complications categorized as bleeding, pneumothorax, and other.

Results

Between August 2021 and April 2022, 15 patients were included in the per-protocol analysis. Six patients were included in cohort 1 and nine patients in cohort 2. A malignant diagnosis was confirmed in 11/15 (73.3%) cases, of which nine were primary lung malignancies. Overall, MVCA in samples obtained by TBFB was significantly larger than TBNA samples {TBFB-MVCA 9.80 mm2 [interquartile range (IQR), 2.70-10.39 mm2] vs. TBNA-MVCA 2.70 mm2 (IQR, 0.14-8.21 mm2), P=0.008}. Despite this difference, molecular testing was feasible in both TBNA and TBFB samples. No major complications were observed.

Conclusions

Despite a significantly smaller MVCA provided by TBNA, samples were still considered feasible for NGS, indicating that TBNA represents an alternative method to obtain sufficient tumor tissue in peripheral nodules as part of the diagnosis of suspected lung cancer.

Utility of bronchoscopically obtained frozen cytology pellets for next-generation sequencing

BACKGROUND

Next-generation sequencing (NGS) is essential for lung cancer treatment. It is important to collect sufficient tissue specimens, but sometimes we cannot obtain large enough samples for NGS analysis. We investigated the yield of NGS analysis by frozen cytology pellets using an Oncomine Comprehensive Assay or Oncomine Precision Assay.

METHODS

We retrospectively enrolled patients with lung cancer who underwent bronchoscopy at Kobe University Hospital and were enrolled in the Lung Cancer Genomic Screening Project for Individualized Medicine. We investigated the amount of extracted DNA and RNA and determined the NGS success rates. We also compared the amount of DNA and RNA by bronchoscopy methods. To create the frozen cytology pellets, we first effectively collected the cells and then quickly centrifuged and cryopreserved them.

RESULTS

A total of 132 patients were enrolled in this study between May 2016 and December 2022; of them, 75 were subjected to frozen cytology pellet examinations and 57 were subjected to frozen tissue examinations. The amount of DNA and RNA obtained by frozen cytology pellets was nearly equivalent to frozen tissues. Frozen cytology pellets collected by endobronchial ultrasound-guided transbronchial needle aspiration yielded significantly more DNA than those collected by transbronchial biopsy methods. (P < 0.01) In RNA content, cytology pellets were not inferior to frozen tissue. The success rate of NGS analysis with frozen cytology pellet specimens was comparable to the success rate of NGS analysis with frozen tissue specimens.

CONCLUSIONS

Our study showed that frozen cytology pellets may have equivalent diagnostic value to frozen tissue for NGS analyses. Bronchial cytology specimens are usually used only for cytology, but NGS analysis is possible if enough cells are collected to create pellet specimens. In particular, the frozen cytology pellets obtained by endobronchial ultrasound-guided transbronchial needle aspiration yielded sufficient amounts of DNA.

TRIAL REGISTRATION

This was registered with the University Medical Hospital Information Network in Japan (UMINCTR registration no. UMIN000052050).

Next-generation sequencing using tissue specimen collected with a 1.1 mm-diameter cryoprobe in patients with lung cancer

BACKGROUND AND OBJECTIVE

Next-generation sequencing (NGS) analysis is considered standard for lung cancer diagnosis in clinical practice. Little is known about the feasibility of NGS using tumour tissue sampled with a 1.1 mm-diameter cryoprobe. We aimed to investigate the suitability of specimens obtained by transbronchial cryobiopsy (TBC) using a 1.1 mm-diameter cryoprobe for NGS analysis.

METHODS

Patients with lung cancer who underwent TBC using a 1.1 mm-diameter cryoprobe for NGS testing between October 2020 and April 2023 were enrolled. A 4.0- or 3.0 mm-diameter bronchoscope with radial probe endobronchial ultrasound and virtual bronchoscopic navigation was used to detect peripheral lung lesions. All procedures were performed under fluoroscopic guidance. Data were analysed retrospectively.

RESULTS

A total of 56 patients underwent TBC using a 1.1 mm cryoprobe for NGS testing, during the study period. Most patients (98%) were in the advanced stage of lung cancer (recurrent or inoperable disease of stages III or IV). The diagnostic yield of NGS for DNA and RNA sequencing was 95% each (53 of 56). Moderate bleeding was noted in three patients (5%) and none of the study patients developed life-threatening complications, such as pneumothorax or lung infection.

CONCLUSION

TBC using a 1.1 mm-diameter cryoprobe is a useful and safe tool for NGS analysis, for both DNA and RNA sequencing.

Clinical application of the Lung Cancer Compact PanelTM using various types of cytological specimens in patients with lung cancer

BACKGROUND

The Lung Cancer Compact PanelTM (compact panel) is a gene panel that can detect driver alterations with high sensitivity in liquid samples, including tumor cells. This study examined the ability of a compact panel to detect genetic mutations in liquid specimens used in clinical practice.

METHODS

Three cohorts, bronchoscopic biopsy forceps washing (washing cohort), pleural effusion (pleural cohort), and spinal fluid (spinal cohort), were analyzed using the compact panel. Liquid samples were added into the GM (Genemetrics) tubes and analyzed. The washing cohort assessed the concordance rate of gene panel analysis outcomes in tissue specimens derived from the primary tumor. Meanwhile, the pleural cohort investigated the impact of storing specimens for 8 weeks and more on nucleic acid and mutation detection rates.

RESULTS

In the washing cohort (n = 79), the concordance rate with mutations detected in tissues was 75/79 (94.9 %). This rate reached 100 % when focusing solely on driver alterations for treatment. The pleural cohort (n = 8) showed no deterioration in nucleic acid quality or quantity after 8 weeks of storage in GM tubes. Similarly, in the spinal cohort (n = 9), spinal fluid with malignant cells exhibited driver alterations similar to those in the primary tumor. These findings underscore the efficacy of the compact panel in accurately identifying genetic mutations in different liquid specimens.

CONCLUSIONS

The compact panel is a reliable tool for detecting driver alterations in various cytological specimens. Its consistent performance across diverse sample types emphasizes its potential for guiding targeted therapies for patients with lung cancer and enhancing precision medicine approaches.

Tissue or liquid rebiopsy? A prospective study for simultaneous tissue and liquid NGS after first-line EGFR inhibitor resistance in lung cancer

INTRODUCTION

According to current International Association for the Study of Lung Cancer guideline, physicians may first use plasma cell-free DNA (cfDNA) methods to identify epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-resistant mechanisms (liquid rebiopsy) for lung cancer. Tissue rebiopsy is recommended if the plasma result is negative. However, this approach has not been evaluated prospectively using next-generation sequencing (NGS).

METHODS

We prospectively enrolled patients with lung cancer with first-line EGFR-TKI resistance who underwent tissue rebiopsy. The rebiopsied tissues and cfDNA were sequenced using targeted NGS, ACTDrug®+, and ACTMonitor®Lung simultaneously. The clinicopathological characteristics and treatment outcomes were analyzed.

RESULTS

Totally, 86 patients were enrolled. Twenty-six (30%) underwent tissue biopsy but the specimens were inadequate for NGS. Among the 60 patients with paired tissue and liquid rebiopsies, two-thirds (40/60) may still be targetable. T790M mutations were found in 29, including 14 (48%) only from tissue and 5 (17%) only from cfDNA. Twenty-four of them were treated with osimertinib, and progression-free survival was longer in patients without detectable T790M in cfDNA than in patients with detectable T790M in cfDNA (p = 0.02). For the 31 T790M-negative patients, there were six with mesenchymal-epithelial transition factor (MET) amplifications, four with ERBB2 amplifications, and one with CCDC6-RET fusion. One with MET amplification and one with ERBB2 amplification responded to subsequent MET and ERBB2 targeting agents respectively.

CONCLUSIONS

NGS after EGFR-TKI resistance may detect targetable drivers besides T790M. To do either liquid or tissue NGS only could miss patients with T790M. To do tissue and liquid NGS in parallel after EGFR-TKI resistance may find more patients with targetable cancers.

Utility of needle biopsy in centrally located lung cancer for genome analysis: a retrospective cohort study

BACKGROUND

It is essential to collect a sufficient amount of tumor tissue for successful next-generation sequencing (NGS) analysis. In this study, we investigated the clinical risk factors for avoiding re-biopsy for NGS analysis (re-genome biopsy) in cases where a sufficient amount of tumor tissue could not be collected by bronchoscopy.

METHODS

We investigated the association between clinical factors and the risk of re-genome biopsy in patients who underwent transbronchial biopsy (TBB) or endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and required re-genome biopsy in cases enrolled in LC-SCRUM Asia, a prospective nationwide genome screening project in Japan. We also examined whether the frequency of re-genome biopsy decreased between the first and second halves of the enrolment period.

RESULTS

Of the 572 eligible patients, 236 underwent TBB, and 134 underwent EBUS-TBNA. Twenty-four TBBs required re-genome biopsy, and multivariate analysis showed that the risk of re-genome biopsy was significantly increased in lesions where the tumor lesion was centrally located. In these cases, EBUS-TBNA should be utilized even if the lesion is a pulmonary lesion. However, it should be noted that even with EBUS-TBNA, lung field lesions are at a higher risk of re-canalization than mediastinal lymph node lesions. It was also found that even when tumor cells were detected in rapid on-site evaluation, a sufficient amount of tumor tissue was not always collected.

CONCLUSIONS

For centrally located pulmonary mass lesions, EBUS-TBNA, rather than TBB, can be used to obtain tumor tissues that can be analyzed by NGS.

Suitability of respiratory endoscopy for sampling malignant thoracic tumors for comprehensive genomic profiling

Comprehensive genomic profiling (CGP) is implemented to detect actionable gene aberrations and design matched therapies. Although malignant thoracic tumors are commonly detected through respiratory endoscopy, it is questionable whether the small specimens obtained thereof are sufficient for CGP. Therefore, this study aimed to investigate the suitability of respiratory endoscopy for sampling primary and metastatic thoracic tumors for CGP. Patients whose specimens were collected through respiratory endoscopy and assessed by pathologists to determine their suitability for CGP at our institution between June 2019 and May 2022 were reviewed retrospectively. The suitability of each procedure as a sampling technique for CGP and, in the cases actually analyzed, the distribution of the detected gene aberration were assessed. In total, 122 patients were eligible for analysis; the median age was 61 (range, 29-86) years, and 71 (58.2%) patients were male. Primary intrathoracic tumors were found in 91 (74.6%) cases, including 84 (68.9%) primary lung cancers; the remaining thoracic metastases of extrathoracic origin included various types. The suitability rates of specimens obtained using conventional bronchoscopy with and without cryobiopsy, endobronchial ultrasound-guided transbronchial needle aspiration, and medical thoracoscopy were 82.8% (24/29), 70.4% (19/27), 72.9% (35/48), and 100% (18/18), respectively. Of the 96 cases judged suitable, 83 were subjected to CGP, and all but one were successfully analyzed. Finally, 47 (56.6%) patients had at least one actionable gene aberration and eight (9.6%) were treated with the corresponding targeted therapies. In conclusion, specimens obtained through respiratory endoscopy are suitable for CGP; medical thoracoscopy and cryobiopsy in conventional bronchoscopy are particularly useful.

Enhancing tumour content and tumour cell count using microdissection contributes to higher detection rate of genetic mutations by next-generation sequencers

Background

Next-generation sequencing (NGS) analysis is becoming indispensable for the treatment of advanced lung cancer. NGS analysis requires a large number of cancer cell-containing tissues; however, it is often difficult for small biopsies to obtain the required quantities. In microdissection, only the tumour parts of a tissue specimen are obtained, which thereby increases the tumour content and tumour cell count of the tissue specimen. In this study, we investigated the extent to which the detection rate of genetic mutations changes by increasing the tumour content using microdissection.

Patients and methods

This is a retrospective study. In the genetic panel test using the Oncomine Dx Target Test (ODxTT), participants were divided into two groups: before (group A; April 2021-March 2022) and after (group B; April 2022-December 2022) the introduction of microdissection. The submission criteria for ODxTT were tumour content and tumour cell count >30 % and >2000 in group A, and >40 % and >5000 in group B, respectively. We compared the rate of genetic mutations detected using ODxTT between the two groups.

Results

This study included 214 consecutive ODxTT cases between April 2021 and December 2022. In group A (n = 112), 65 cases were adenocarcinoma, 84 involved lung tissue, and 64 underwent bronchoscopic sampling, whereas in group B (n = 102), 55 cases were adenocarcinoma, 91 cases involved lung tissue, and 79 cases underwent bronchoscopic sampling. Furthermore, genetic mutations were detected in 39 of 112 cases (35 %) in group A and 59 of 102 cases (58 %) in group B, which was statistically higher in group B (P = 0.0006). Genetic mutations were detected in 45 of 55 adenocarcinoma cases in group B. The genetic mutations detected in epidermal growth factor rescepor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), and mesenchymal epithelial transition (MET) were higher in group B.

Conclusion

Increasing the number of tumour cells and tumour content can enhance the detection rate of genetic mutations using ODxTT.

Clinical application of the AMOY 9-in-1 panel to lung cancer patients

INTRODUCTION

To investigate the clinical performance of the AMOY 9-in-1 kit (AMOY) in comparison with a next-generation sequencing (NGS) panel in lung cancer patients.

METHODS

Lung cancer patients enrolled in the LC-SCRUM-Asia program at a single institution were analyzed for the success rate of AMOY analysis, the detection rate of targetable driver mutations, the turn around time (TAT) from specimen submission to the result reporting, and the concordance rate of results with the NGS panel.

RESULTS

Of the 406 patients included in the analysis, 81.3% had lung adenocarcinoma. The success rates of AMOY and NGS were 98.5% and 87.8%, respectively. With AMOY, genetic alterations were detected in 54.9% of cases. Of the 42 cases in which NGS analysis failed, targetable driver mutations were detected by AMOY in ten cases through analysis of the same sample. Of the 347 patients for whom the AMOY and NGS panels were successful, 22 showed inconsistent results. In four of the 22 cases, the mutation was detected only in the NGS panel because AMOY did not cover the EGFR mutant variant. Mutations were detected only by AMOY in five of the six discordant pleural fluid samples, with AMOY having a higher detection rate than NGS. The TAT was significantly shorter five days after AMOY.

CONCLUSION

AMOY had a higher success rate, shorter turnaround time, and higher detection rate than NGS panels. Only a limited number of mutant variants were included; thus be careful not to miss promising targetable driver mutations.

NSCLC in the Era of Targeted and Immunotherapy: What Every Pulmonologist Must Know

The treatment of non-small cell lung cancer has dramatically changed over the last decade through the use of targeted therapies and immunotherapies. Implementation of these treatment regimens relies on detailed knowledge regarding each tumor’s specific genomic profile, underscoring the necessity of obtaining superior diagnostic tissue specimens. While these treatment approaches are commonly utilized in the metastatic setting, approval among earlier-stage disease will continue to rise, highlighting the importance of early and comprehensive biomarker testing at the time of diagnosis for all patients. Pulmonologists play an integral role in the diagnosis and staging of non-small cell lung cancer via sophisticated tissue sampling techniques. This multifaceted review will highlight current indications for the use of targeted therapies and immunotherapies in non-small cell lung cancer and will outline the quality of various diagnostic approaches and subsequent success of tissue biomarker testing. Pulmonologist-specific methods, including endobronchial ultrasound and guided bronchoscopy, will be examined as well as other modalities such as CT-guided transthoracic biopsy and more.

Rapid and reliable collection of tumor tissue for successful gene panel in a patient with advanced stage lung cancer: A case report

Rapid and reliable identification of targetable driver mutations in patients with advanced stage lung cancer is essential. Adequate amount of tumor tissue biopsies (i.e., genomic biopsies) are required to successfully analyze the gene panel. In the present case, we performed three pleural fluid investigations, including transbronchial biopsy of the primary tumor, transesophageal endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of lymph node metastasis, and thoracoscopic biopsy of the pleural seeding sites. Among the three investigations, thoracoscopic biopsy alone successfully obtained a sufficient amount of tissue. Thus, it is important to determine the technique and site of biopsy, as multiple biopsies are not only burdensome to the patient, but also lead to significant delays in therapy induction.

Clinical application of comprehensive genomic profiling panel to thoracic malignancies: A single-center retrospective study

BACKGROUND

The usefulness of comprehensive genomic profiling (CGP) panels for thoracic malignancies after completion of the standard treatment is unclear.

METHODS

The results of CGP panels for malignant thoracic diseases performed at our hospital between December 2019 and June 2022 were collected. We examined whether CGP panel results led to new treatment, correlated with the effectiveness of immune checkpoint inhibitors (ICIs), or revealed secondary findings related to hereditary tumors.

RESULTS

A total of 60 patients were enrolled, of which 52 (86.6%) had lung cancer. In six (10%) patients, the panel results led to treatment with insurance-listed molecular-targeted agents; four patients had EGFR mutations not detected by the real-time polymerase chain reaction assay and two had MET ex.14 skipping mutations. In small-cell lung cancer, the tumor mutation burden was high in 4/6 (66.7%) patients and pembrolizumab was available. Another MET ex.14 skipping mutation was detected in two cases with EGFR-tyrosine kinase inhibitor resistance. ICI efficacy was ≤1 year in patients with STK-11, KEAP1, and NEF2L2 mutations. A BRCA2 mutation with a high probability of germline mutation was detected in one patient. A thymic carcinoma with no detectable oncogenic mutation responded to second-line treatment with Tegafur-Gimeracil-Oteracil Potassium (TS-1) for ≥9 years.

CONCLUSIONS

CGP panels are useful in thoracic malignancies, especially lung cancer, because they can detect overlooked driver mutations and genetic alterations. We believe that the significance of conducting a CGP panel prior to treatment may also exist, as it may lead to the prediction of ICI treatment efficacy.

Expanding the Full Potential of Liquid Biopsies for Lung Cancer Patients

In recent years, there has been tremendous therapeutic progress for advanced lung cancer, leading to the identification of a multitude of therapeutic targets and significantly expanding the list of potential target genes to be tested. However, precision oncology requires knowledge of the exact biology of the tumor through sequencing of the cancer genome, which is hampered by limited tissue availability in thoracic malignancies. Liquid biopsy, namely plasma cell-free DNA (cfDNA) analysis, has expanded these opportunities and is now firmly established in the diagnostic algorithm of patients with lung cancer with metastatic disease. However, the full potential of this powerful tool has been largely underexplored. In this issue of Cancer Research, Nair and colleagues provide evidence of the clinical utility of bronchoalveolar lavage (BAL) cfDNA profiling through an ultra-deep next-generation sequencing approach. The study findings support further development of BAL cfDNA analysis for tumor genotyping, besides the current gold standard sources (tissue and plasma), as a complementary tool in patients undergoing diagnostic bronchoscopy for tumor diagnosis and/or rebiopsy, increasing the success rates of genomic analyses. In addition, BAL cfDNA profiling might represent an important diagnostic tool in early-stage lung cancer, outperforming plasma cfDNA in stage I-II and detecting field cancerization signs, potentially identifying tumors before their clinical appearance. Further studies should confirm the full potential of BAL cfDNA profiling in lung cancer and its place in the large family of liquid biopsies. See related article by Nair et al., p. 2838.