Comparison of next-generation sequencing and immunohistochemistry analysis for targeted therapy-related genomic status in lung cancer patients

Localization of epidermal growth factor receptor-mutations using PNA:DNA probes in clinical specimens from patients with non-small cell lung cancer

Quickly identifying driver gene mutations in solid cancers is important. However, next-generation sequencing (NGS)-based mutation detection methods are time-consuming and expensive. Peptide nucleic acid (PNA) probe-based mutant mRNA detection systems are quick and inexpensive. We previously demonstrated that epidermal growth factor receptor (EGFR)-mutations were efficiently visualized in formalin-fixed paraffin-embedded (FFPE) specimens from transplanted non-small cell lung cancer (NSCLC) tumors using an EGFR mutation-specific PNA:DNA probe. Herein, the efficiency of PNA:DNA probes in detecting EGFR-mutations in FFPE specimens from patients with NSCLC and the colocalization of EGFR-mutations with tumor-infiltrating lymphocyte (TIL) status were determined. The EGFR mutation L858R-specific PNA:DNA probe detected heterogeneously localized mutations with a sensitivity similar to detection with the anti-L858R antibody. TIL analysis of L858R-mutated tumors revealed that CD8+PD-1+ T cells and CD68+ macrophages were scarce in tumors, but in the cytokeratin-positive intra-tumoral regions, CD4+, FoxP3+, and CD204+ cells tended to be more abundant in the L858R-positive tumor area than in the negative area. Thus, PNA:DNA probes specific for EGFR-mutations can detect areas with heterogeneous EGFR mutants in whole cancer tissues and can be used to evaluate the mutation-associated TIL status in EGFR-mutant cancer tissues.

Unravelling the complexity of EGFR-mutated lung adenocarcinoma: a unique case report with histological transformations and co-alteration acquisition

Background

Osimertinib, a third-generation tyrosine kinase inhibitor that targets epidermal growth factor receptor (EGFR), specifically inhibits both EGFR tyrosine kinase inhibitor-sensitive mutations and T790M resistance mutations. Despite initial positive responses to EGFR tyrosine kinase inhibitors, nearly all patients eventually experience disease progression. Mechanisms of resistance are classically divided into EGFR-dependent and EGFR-independent mechanisms, such as the activation of alternative pathways and histological changes. We report a case of histological transformation into large cell carcinoma associated with the subsequent acquisition of an anaplastic lymphoma kinase (ALK) rearrangement after osimertinib exposure.

Case Description

A 67-year-old female with no smoking history presented with supraclavicular lymphadenopathy and asthenia, which led to a diagnosis of stage IVB lung adenocarcinoma. Next generation sequencing (NGS) identified an EGFR Ex19del mutation, which suggested the use of afatinib, as it was prescribed prior to osimertinib and was covered by insurance. Initial treatment with afatinib resulted in partial remission, followed by pulmonary progression without the EGFR-T790M mutation. Moreover, ALK and ROS1 were identified through immunohistochemistry (IHC), with ROS1 expression subsequently confirmed by fluorescence in situ hybridization (FISH); this prompted a switch to crizotinib, which was discontinued owing to further disease progression. Osimertinib was then administered, which resulted in a significant positive response; however, after six months pulmonary progression was observed. A subsequent biopsy indicated a transformation to large cell neuroendocrine carcinoma, which led to treatment with platinum-etoposide chemotherapy and, later, paclitaxel and osimertinib, both of which are partially effective. Finally, a new biopsy confirmed ALK positivity in a large cell neuroendocrine carcinoma that was still harbouring an EGFR exon 19 deletion, so alectinib was introduced.

Conclusions

To our knowledge, this case is the first reported incidence of transformation into large cell carcinoma coupled with a second acquisition of alterations in ALK. These findings underscore the necessity of monitoring patients with oncogenic addiction through both liquid biopsy for on-target mechanism detection and tissue sampling to detect histological transformations. These mechanisms can occasionally be combined, thereby providing comprehensive panels at each stage of tumour progression.

American Association of Bronchology and Interventional Pulmonology Essential Knowledge in Interventional Pulmonology Series: Selected Topics in Malignant Pleural Disease

The goal of the American Association of Bronchology and Interventional Pulmonology Essential Knowledge in Interventional Pulmonology Series is to provide clinicians with concise, up-to-date reviews of important topics in the field of interventional pulmonology. This 3-year alternating rotation of primary topics will start with a focus on selected topics in malignant pleural disease. In this article, we update the reader on malignant pleural effusion in 3 parts: part 1-diagnosis, focusing on imaging and fluid biomarkers; part 2-management, with review of multimodal approaches, cost considerations, and evolving targeted therapies; and part 3-pleural mesothelioma. These reviews complement the Essential Knowledge in Interventional Pulmonology Lecture Series presented at the 2023 AABIP Annual Conference, available for viewing on the AABIP website (https://aabip.memberclicks.net/essential-knowledge-in-interventional-pulmonology-series).

Rediscovering immunohistochemistry in lung cancer

Several observations indicate that protein expression analysis by immunohistochemistry (IHC) remains relevant in individuals with non-small-cell lung cancer (NSCLC) when considering targeted therapy, as an early step in diagnosis and for therapy selection. Since the advent of next-generation sequencing (NGS), the role of IHC in testing for NSCLC biomarkers has been forgotten or ignored. We discuss how protein-level investigations maintain a critical role in defining sensitivity to lung cancer therapies in oncogene- and non-oncogene-addicted cases and in patients eligible for immunotherapy, suggesting that IHC testing should be reconsidered in clinical practice. We also argue how a panel of IHC tests should be considered complementary to NGS and other genomic assays. This is relevant to current clinical diagnostic practice but with potential future roles to optimize the selection of patients for innovative therapies. At the same time, strict validation of antibodies, assays, scoring systems, and intra- and interobserver reproducibility is needed.

Congenital heart diseases (CHDs) and forensic investigations: Searching for the cause of death

Congenital Heart Diseases (CHDs) are a group of structural abnormalities or defects of the heart that are present at birth. CHDs could be connected to sudden death (SD), defined by the WHO (World Health Organization) as "death occurring within 24 h after the onset of the symptoms" in an apparently "healthy" subject. These conditions can range from relatively mild defects to severe, life-threatening anomalies. The prevalence of CHDs varies across populations, but they affect millions of individuals worldwide. This article aims to discuss the post-mortem investigation of death related to CHDs, exploring the forensic approach, current methodologies, challenges, and potential advancements in this challenging field. A further goal of this article is to provide a guide for understanding these complex diseases, highlighting the pivotal role of autopsy, histopathology, and genetic investigations in defining the cause of death, and providing evidence about the translational use of autopsy reports. Forensic investigations play a crucial role in understanding the complexities of CHDs and determining the cause of death accurately. Through collaboration between medical professionals and forensic experts, meticulous examinations, and analysis of evidence, valuable insights can be gained. These insights not only provide closure to the families affected but also contribute to the prevention of future tragedies.

Molecular Profiling in Non-Squamous Non-Small Cell Lung Carcinoma: Towards a Switch to Next-Generation Sequencing Reflex Testing

Molecular diagnosis of lung cancer is a constantly evolving field thanks to major advances in precision oncology. The wide range of actionable molecular alterations in non-squamous non-small cell lung carcinoma (NS-NSCLC) and the multiplicity of mechanisms of resistance to treatment resulted in the need for repeated testing to establish an accurate molecular diagnosis, as well as to track disease evolution over time. While assessing the increasing complexity of the molecular composition of tumors at baseline, as well as over time, has become increasingly challenging, the emergence and implementation of next-generation sequencing (NGS) testing has extensively facilitated molecular profiling in NS-NSCLC. In this review, we discuss recent developments in the molecular profiling of NS-NSCLC and how NGS addresses current needs, as well as how it can be implemented to address future challenges in the management of NS-NSCLC.

Lung adenocarcinoma harboring complex EML4-ALK fusion and BRAF V600E co-mutation responded to alectinib

RATIONALE

The echinoderm microtubule-associated protein-like 4 gene and anaplastic lymphoma kinase gene (EML4-ALK) is the most frequent fusion variant of ALK rearrangements in non-small cell lung cancer (NSCLC). With the widespread application of next-generation sequencing (NGS), more fusions and co-mutations of EML4-ALK have been discovered. Complex co-mutation of EML4-ALK fusions together with BRAF V600E, though rarely occurred, also deserves attention to determine the standard of caring these patients. Herein, we report a case of lung adenocarcinoma harboring a complex ALK fusion that coexisted with a BRAF mutation, as tested by DNA-NGS prior to treatment.

PATIENT CONCERNS

A 51-year-old non-smoking man, without any symptoms, was admitted to hospital due to small pulmonary nodules and enlarged supraclavicu larlymph nodes found in health checkup.

DIAGNOSIS

He was diagnosed with stage IVB (T4N3M1c) lung adenocarcinoma. BRAF V600E (abundance 3.75%) mutation and a novel thus little-understood EML4-ALK (E13, A5; abundance 2.16%) fusion were identified by DNA-NGS analysis of lymph node biopsy tissue in December 2019.

INTERVENTIONS

Darafenib plus trametinib targeted therapy and chemotherapy were given firstly, but tumor progression was not inhibited. The ALK inhibitor alectinib was prescribed then.

OUTCOMES

The patient exhibited a rapid disease response to ALK tyrosine kinase inhibitors alectinib with a complete remission of widespread metastatic disease and progression-free survival of more than 26 months, but not to darafenib plus trametinib targeted BRAF V600E therapy. Re-analyzed the patient's DNA-NGS original data, showed it is a rare and complex EML4-ALK (E13, A5, A20) fusion in fact. Additional RNA-NGS analysis showed it verified to be a canonical EML4-ALK (E13, A20) fusion transcript and coexisting with a BRAF V600E mutation.

LESSONS

This case suggests that for patients with rare or complex EML4-ALK fusions at DNA level, additional RNA-NGS is necessary to verify its functionality as early as possible. Targeting EML4-ALK firstly may be more preferable despite the coexisting of BRAF V600E.

ROS1-positive non-small cell lung cancer (NSCLC): biology, diagnostics, therapeutics and resistance

ROS1 is a proto-oncogene encoding a receptor tyrosine protein kinase (RTK), homologous to the v - Ros sequence of University of Manchester tumours virus 2 (UR2) sarcoma virus, whose ligands are still being investigated. ROS1 fusion genes have been identified in various types of tumours. As an oncoprotein, it promotes cell proliferation, activation and cell cycle progression by activating downstream signalling pathways, accelerating the development and progression of non-small cell lung cancer (NSCLC). Studies have demonstrated that ROS1 inhibitors are effective in patients with ROS1-positive NSCLC and are used for first-line clinical treatment. These small molecule inhibitors provide a rational therapeutic option for the treatment of ROS1-positive patients. Inevitably, ROS1 inhibitor resistance mutations occur, leading to tumours recurrence or progression. Here, we comprehensively review the identified biological properties and Differential subcellular localisation of ROS1 fusion oncoprotein promotes tumours progression. We summarise recently completed and ongoing clinical trials of the classic and new ROS1 inhibitors. More importantly, we classify the complex evolving tumours cell resistance mechanisms. This review contributes to our understanding of the biological properties of ROS1 and current therapeutic advances and resistant tumours cells, and the future directions to develop ROS1 inhibitors with durable effects.

Comparison of Next-Generation Sequencing and Polymerase Chain Reaction for Personalized Treatment-Related Genomic Status in Patients with Metastatic Colorectal Cancer

Personalized treatments based on the genetic profiles of tumors can simultaneously optimize efficacy and minimize toxicity, which is beneficial for improving patient outcomes. This study aimed to integrate gene alterations associated with predictive and prognostic outcomes in patients with metastatic colorectal cancer (mCRC) with polymerase chain reaction (PCR) and in-house next-generation sequencing (NGS) to detect KRAS, NRAS, and BRAF mutations. In the present study, 41 patients with mCRC were assessed between August 2017 and June 2019 at a single institution. The overall concordance between NGS and PCR results for detecting KRAS, NRAS, and BRAF mutations was considerably high (87.8-92.7%), with only 15 discrepant results between PCR and NGS. Our companion diagnostic test analyzes KRAS, NRAS, and BRAF as a panel of CRC molecular targets; therefore, it has the advantages of requiring fewer specimens and being more time and cost efficient than conventional testing for separate analyses, allowing for the simultaneous analysis of multiple genes.

Precision diagnostics: Integration of tissue pathology and genomics in cancer

Traditionally, cancer diagnosis and management has been reactionary in that symptoms lead to investigations, then a diagnosis is followed by clinical management. This process is heavily dependent on tissue diagnosis mainly by histopathology and to a lesser extent, cytopathology. However, in recent times there has been a shift towards precision medicine to enable prevention, prediction and personalisation in healthcare. The core of precision medicine is optimising therapeutic benefit for patients, by using genomic and molecular profiling, analogously termed precision pathology. This review explores (1) the evolution of pathology from a para-clinical discipline to a mainstream medical field integral to oncology tumour boards; (2) its critical role in preventative, diagnostic, therapeutic and follow-up cancer care; (3) the future of tissue pathology in the era of precision oncology; and (4) how pathologists may evolve to future-proof their profession.

Genomic alteration profiles of lung cancer and their relationship to clinical features and prognosis value using individualized genetic testing

Background

This study aimed to use a panel targeting 197 genes and 38 fusions to observe the features of gene variations in lung cancer patients, as well as their prognostic values.

Methods

Patients admitted to our hospital between 2016 and 2017 were enrolled. All patients received OseqTM-Drug genetic testing using peripheral venous blood, followed by 1–2 years of observation.

Results

For all included patients, 32 genes were observed with mutations. EGFR exhibited the highest mutation rate (46.5%), followed by TP53. The majority of patients carried only one mutant gene. Interestingly, 18 (41.8%) patients showed no mutations, and some cases carried mutations in six genes simultaneously. There was no statistical relationship between mutations and demographic influence. Pathological subtypes were associated with mutations including FLI1, IGF1R, and NOTCH1. A significant correlation was observed between mutant genes and stage at diagnosis, however this requires further confirmation as there was only one case in these mutations: AKT2, AR, STK11, VEGFA, HDAC6, and ASPSCR. For the 33 patients with lymph node metastases at the time of diagnosis, no correlation with any gene mutant was found. Finally, no associations between the survival or prognosis indices (1-year survival, 1-year progression, progression free survival (PFS), and overall survival (OS)) were observed with gene mutations.

Conclusions

Together, individualized genetic testing is a feasible and minimally invasive approach in cancer genetic analysis. However, gene mutation detection has a limited efficacy in the prediction of prognosis.

Histologic and Molecular Characterization of Non-Small Cell Lung Carcinoma With Discordant ROS1 Immunohistochemistry and Fluorescence In Situ Hybridization

INTRODUCTION

ROS1 immunohistochemical (IHC) positivity requires follow-up with confirmatory testing such as fluorescence in situ hybridization (FISH). Identifying predictive characteristics of false positive ROS1 IHC cases could aid in optimizing testing algorithms, decrease testing costs and preserve tissue.

MATERIALS AND METHODS

Retrospective results were retrieved for 2054 patients with non-small cell lung carcinoma submitted to our laboratory for molecular testing. Reflex ROS1 FISH was done on all ROS1 immunoreactive cases using ROS1 D4D6 antibody. Staining intensity and histo-score was recorded for all ROS1 immunoreactive cases. Results of any additional molecular testing (KRAS, BRAF, EGFR, ALK FISH, RET FISH, MET FISH) were also tabulated.

RESULTS

ROS1 immunoreactivity was seen in 305/2054 (14.8%) cases. Immunoreactivity was weak in majority of the cases with only 4.6% cases having an histo-score >100 and 5.9% of cases had moderate staining intensity. FISH was negative in 99% (302/305) cases with any degree of IHC expression (discordant cases) while 3 cases were positive by FISH. Diffuse strong IHC staining in greater than 90% of the tumor was noted in 6 cases, 3 (0.98%) of which were confirmed to have ROS1 rearrangement by FISH. The discordant cases had significantly higher rates of EGFR mutations (P<0.0005) in comparison to ROS1 IHC negative cases, were seen more often in adenocarcinoma and adenosquamous cell carcinoma (P<0.0005) with lepidic and acinar patterns, and more likely to occur in primary lung carcinomas (P<0.0005).

CONCLUSIONS

False positive ROS1 immunoreactivity was very frequent, occurred more commonly in primary NSCLC cases with acinar and/or lepidic histologies and was more likely in EGFR mutated cases. Using higher positivity thresholds for ROS1 IHC and incorporating the histologic and molecular correlates into algorithmic strategies could result in increased specificity and clinical utility of ROS1 IHC assay.

Comparison of the Data of a Next-Generation Sequencing Panel from K-MASTER Project with that of Orthogonal Methods for Detecting Targetable Genetic Alterations

Purpose

K-MASTER project is a Korean national precision medicine platform that screened actionable mutations by analyzing next-generation sequencing (NGS) of solid tumor patients. We compared gene analyses between NGS panel from the K-MASTER project and orthogonal methods.

Materials and Methods

Colorectal, breast, non–small cell lung, and gastric cancer patients were included. We compared NGS results from K-MASTER projects with those of non-NGS orthogonal methods (KRAS, NRAS, and BRAF mutations in colorectal cancer [CRC]; epidermal growth factor receptor [EGFR], anaplastic lymphoma kinase [ALK] fusion, and reactive oxygen species 1 [ROS1] fusion in non–small cell lung cancer [NSCLC], and Erb-B2 receptor tyrosine kinase 2 (ERBB2) positivity in breast and gastric cancers).

Results

In the CRC cohort (n=225), the sensitivity and specificity of NGS were 87.4% and 79.3% (KRAS); 88.9% and 98.9% (NRAS); and 77.8% and 100.0% (BRAF), respectively. In the NSCLC cohort (n=109), the sensitivity and specificity of NGS for EGFR were 86.2% and 97.5%, respectively. The concordance rate for ALK fusion was 100%, but ROS1 fusion was positive in only one of three cases that were positive in orthogonal tests. In the breast cancer cohort (n=260), ERBB2 amplification was detected in 45 by NGS. Compared with orthogonal methods that integrated immunohistochemistry and in situ hybridization, sensitivity and specificity were 53.7% and 99.4%, respectively. In the gastric cancer cohort (n=64), ERBB2 amplification was detected in six by NGS. Compared with orthogonal methods, sensitivity and specificity were 62.5% and 98.2%, respectively.

Conclusion

The results of the K-MASTER NGS panel and orthogonal methods showed a different degree of agreement for each genetic alteration, but generally showed a high agreement rate.

IHC versus FISH versus NGS to detect ALK gene rearrangement in NSCLC: all questions answered?

AIMS

Anaplastic lymphoma kinase (ALK) rearranged non-small cell lung carcinoma (NSCLC) is a distinct molecular subtype and rapid approval of ALK tyrosine kinase inhibitors (TKIs) has necessitated rapid and sensitive diagnostic modalities for the detection of this alteration. Gene rearrangements can be identified using many techniques including fluorescence in situ hybridisation (FISH), reverse transcriptase-PCR, next-generation sequencing (NGS) and immunohistochemistry (IHC) for fusion oncoprotein expression. We aimed to determine the concordance between IHC, FISH and NGS for ALK biomarker detection, and determine differences in sensitivity, and survival outcomes.

METHODS

We analysed the concordance between IHC using D5F3 monoclonal antibody, FISH (break-apart) and NGS using a custom panel containing 71 different ALK variants.

RESULTS

Among 71 cases included in this study, FISH was evaluable in 58 cases. The concordance of ALK IHC with FISH was 75.9% and that with NGS was 84.5%. The sensitivities of FISH and NGS were 75.6% and 87.5%, respectively. The median progression-free survival of ALK IHC-positive and FISH-negative group was 5.5 months and that of both positive was 9.97 months.

CONCLUSION

Although NGS offers a better throughput and visualisation, IHC still remains the quintessential screening tool in upfront diagnosis of ALK rearranged NSCLC.

Correlating ROS1 Protein Expression With ROS1 Fusions, Amplifications, and Mutations

INTRODUCTION

In this study, we sought to further characterize ROS1 protein expression in solid tumors with the complete spectrum of ROS1 genomic alterations.

METHODS

ROS1 immunohistochemistry (IHC) was performed using the ROS1 (SP384) class I assay per manufacturer's instructions on a variety of solid tumors (n = 32) with known ROS1 genomic alterations. Genomic alterations included fusions (n = 17), gene amplifications (n = 10), and short-variant mutations (n = 11).

RESULTS

Of the 32 cases with ROS1 IHC results, 100% (11 of 11) with canonical ROS1 fusions were positive for ROS1 IHC. Among noncanonical ROS1 fusions, only two (of five) cases with SQSTM1-ROS1 and RDX-ROS1 fusions were positive for ROS1 IHC whereas PTPRK-ROS1 (two) and TTC28-ROS1 fusions were negative for ROS1 IHC. One sample with a canonical ROS1 fusion and co-occurring ROS1 resistance mutation (6094G>A, p.G2032R) was positive for ROS1 IHC. A total of 10% (one of 10) of ROS1 amplified tumors were positive for ROS1 IHC. None of the cases (zero of five) with ROS1 short-variant mutations were positive for ROS1 protein expression.

CONCLUSIONS

These findings suggest that if ROS1 IHC was used as a screening tool for ROS1 fusion, a subset of fusion-negative tumors will reveal positive IHC staining highlighting the value of reflexing to genomic profiling to confirm the presence of a targetable fusion-driver before the initiation of therapy. In addition, the ability of comprehensive genomic profiling to detect ROS1 resistance mutations will be important for clinical decision making.

Aptamers in Non-Small Cell Lung Cancer Treatment

Aptamers are short, single-stranded oligonucleotides which are capable of specifically binding to single molecules and cellular structures. Aptamers are also known as “chemical antibodies”. Compared to monoclonal antibodies, they are characterized by higher reaction specificity, lower molecular weight, lower production costs, and lower variability in the production stage. Aptamer research has been extended during the past twenty years, but only Macugen^® has been accepted by the Food and Drug Administration (FDA) to date, and few aptamers have been examined in clinical trials. In vitro studies with aptamers have shown that they may take part in the regulation of cancer progression, angiogenesis, and metastasis processes. In this article, we focus on the potential use of aptamers in non-small cell lung cancer treatment.