Profile of Ventana ALK (D5F3) companion diagnostic assay for non-small-cell lung carcinomas

Immunohistochemical detection of cancer genetic abnormalities

New applications of immunohistochemistry (IHC) expand rapidly due to the development of molecular analyses and an increased understanding of molecular biology. IHC becomes much more important as a screening or even a confirmatory test for molecular changes in cancer. The past decades have witnessed the release of many immunohistochemical markers of the new generation. The novel markers have extensively high specificity and sensitivity for the detection of genetic abnormalities. In addition to diagnostic utility, IHC has been validated to be a practical tool in terms of treatments, especially molecular targeted therapy. In this review, we first describe the common alterations of protein IHC staining in human cancer: overexpression, underexpression, or loss of expression and altered staining pattern. Next, we examine the relationship between staining patterns and genetic aberrations regarding both conventional and novel IHC markers. We also mention current mutant-specific and fusion-specific antibodies and their concordance with molecular techniques. We then describe the basic molecular mechanisms from genetic events to corresponding protein expression patterns (membranous, cytoplasmic, or nuclear patterns). Finally, we shortly discuss the applications of immunohistochemistry in molecular targeted therapy. IHC markers can serve as a complementary or companion diagnostic test to provide valuable information for targeted therapy. Moreover, immunohistochemistry is also crucial as a companion diagnostic test in immunotherapy. The increased number of IHC novel antibodies is broadening its application in anti-cancer therapies.

[New update to the guidelines on testing predictive biomarkers in non-small-cell lung cancer: a National Consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology]

Non-small cell lung cancer (NSCLC) presents the greatest number of identified therapeutic targets, some of which have therapeutic utility. Currently, detecting EGFR, BRAF, KRAS and MET mutations, ALK, ROS1, NTRK and RET translocations, and PD-L1 expression in these patients is considered essential. The use of next-generation sequencing (NGS) facilitates precise molecular diagnosis and allows the detection of other emerging mutations, such as the HER2 mutation and predictive biomarkers for immunotherapy responses. In this consensus, a group of experts in the diagnosis and treatment of NSCLC selected by the Spanish Society of Pathology (SEAP) and the Spanish Society of Medical Oncology (SEOM) have evaluated currently available information and propose a series of recommendations to optimize the detection and use of biomarkers in daily clinical practice.

New update to the guidelines on testing predictive biomarkers in non-small-cell lung cancer: a National Consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology

Non-small cell lung cancer (NSCLC) presents the greatest number of identified therapeutic targets, some of which have therapeutic utility. Currently, detecting EGFR, BRAF, KRAS and MET mutations, ALK, ROS1, NTRK and RET translocations, and PD-L1 expression in these patients is considered essential. The use of next-generation sequencing facilitates precise molecular diagnosis and allows the detection of other emerging mutations, such as the HER2 mutation and predictive biomarkers for immunotherapy responses. In this consensus, a group of experts in the diagnosis and treatment of NSCLC selected by the Spanish Society of Pathology and the Spanish Society of Medical Oncology have evaluated currently available information and propose a series of recommendations to optimize the detection and use of biomarkers in daily clinical practice.

Current status and challenges of immunotherapy in ALK rearranged NSCLC

Rearrangements of the anaplastic lymphoma kinase (ALK) gene account for 5-6% in non-small cell lung cancer (NSCLC). ALK rearranged NSCLC is sensitive to ALK tyrosine kinase inhibitors (TKIs) but prone to drug resistance. Meanwhile, ALK rearranged NSCLC has poor response to single immunotherapy. Here we mainly describe the immune escape mechanisms of ALK mutated NSCLC and the role of related biomarkers. Additionally, we collate and evaluate preclinical and clinical studies of novel immune combination regimens, and describe the prospects and perspectives for the in vivo application of novel immune technologies in patients with ALK rearranged NSCLC.

Real-world treatment patterns and outcomes among patients with advanced non-small-cell lung cancer with spindle cell and/or giant cell carcinoma

Objectives

A definitive diagnosis of pulmonary sarcomatoid carcinoma cannot be made with small biopsies. In clinical practice, a diagnosis of advanced non-small-cell lung cancer with spindle cell and/or giant cell carcinoma (NSCLCsg), or possible sarcomatoid carcinoma, is acceptable. Therefore, we aimed to investigate the treatment patterns and outcomes of advanced NSCLCsg.

Materials and methods

Between 01 January 2012 and 01 April 2021, patients with pathologically proven advanced NSCLCsg were enrolled. The choice of treatment was based on clinician discretion.

Results

In all, 101 patients with advanced NSCLCsg were enrolled. In total, 77 (76.2%) patients received at least one line of systemic therapy; 44 patients (43.1%) had received platinum doublet chemotherapy; 27 (26.7%) patients had been treated with targeted therapies; and 23 patients (22.8%) had been given an immune checkpoint inhibitor (ICI). The median overall survival (OS) was 6.3 months [95% confidence interval (CI): 3.6-9.0 months]. Excluding patients without systemic therapy, patients who had received an ICI had better OS (median: 18.2 months) than those who had not (median 3.8 months, log-rank test p = 0.002). No significant difference in OS was detected between patients who had or had not received platinum doublet chemotherapy (log-rank test p = 0.279), or targeted therapy (log-rank test p = 0.416). Having received any systemic therapy [hazard ratio (HR): 0.33, 95% CI: 0.18-0.61, p < 0.0001) and ICI (HR: 0.38, 95% CI: 0.19-0.78, p = 0.008) were independent factors for better OS. Patients with programmed death ligand-1 (PD-L1) expression ⩾50% had better OS than those with PD-L1 expression <50% (HR: 0.51, 95%: 0.30-0.86, p = 0.012).

Conclusion

Although advanced NSCLCsg has a poor survival outcome, our results showed that ICI may prolong OS in patients with advanced NSCLCsg. Further prospective studies are warranted to gain more understanding of the role of ICI in this specific patient population.

Evaluation of the Molecular Landscape in PD-L1 Positive Metastatic NSCLC: Data from Campania, Italy

Background: Immune-checkpoint inhibitors (ICIs) have increased and improved the treatment options for patients with non-oncogene-addicted advanced stage non-small cell lung cancer (NSCLC). However, the role of ICIs in oncogene-addicted advanced stage NSCLC patients is still debated. In this study, in an attempt to fill in the informational gap on the effect of ICIs on other driver mutations, we set out to provide a molecular landscape of clinically relevant oncogenic drivers in programmed death-ligand 1 (PD-L1) positive NSCLC patients. Methods: We retrospectively reviewed data on 167 advanced stage NSCLC PD-L1 positive patients (≥1%) who were referred to our clinic for molecular evaluation of five driver oncogenes, namely, EGFR, KRAS, BRAF, ALK and ROS1. Results: Interestingly, n = 93 (55.7%) patients showed at least one genomic alteration within the tested genes. Furthermore, analyzing a subset of patients with PD-L1 tumor proportion score (TPS) ≥ 50% and concomitant gene alterations (n = 8), we found that n = 3 (37.5%) of these patients feature clinical benefit with ICIs administration, despite the presence of a concomitant KRAS gene alteration. Conclusions: In this study, we provide a molecular landscape of clinically relevant biomarkers in NSCLC PD-L1 positive patients, along with data evidencing the clinical benefit of ICIs in patient NSCLC PD-L1 positive alterations.

Detecting anaplastic lymphoma kinase (ALK) gene rearrangements with next-generation sequencing remains a reliable approach in patients with non-small-cell lung cancer

Next-generation sequencing (NGS) is rapidly becoming routine in clinical oncology practice to identify therapeutic biomarkers, including gene rearrangements in anaplastic lymphoma kinase (ALK). Our study investigated the concordance of ALK positivity evaluated by DNA-based NGS with orthogonal ALK testing methods such as fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), and RNA-based NGS (RNA-NGS). Thirty-eight patients with lung adenocarcinoma who were detected with ALK rearrangements using DNA-NGS and also had adequate tissue samples submitted for FISH, IHC, and RNA-NGS, were included in this study. Of the 38 patients, RNA samples from 3 patients failed quality control for RNA-NGS. The concordance of ALK positivity was calculated relative to DNA-NGS results. The concordance rates were 97.1% (34/35) for RNA-NGS, 94.7% (36/38) for IHC, and 97.4% (37/38) for FISH. DNA-NGS detected single ALK rearrangements in 14 (35.0%) patients and complex ALK rearrangements in 26 (65.0%). RNA-NGS detected only single transcripts of the primary ALK fusions. A novel LANCL1-ALK (L7:A20) detected using DNA-NGS was detected as EML4-ALK (E13:A20) transcripts using RNA-NGS. Interestingly, patients with single ALK rearrangements were more likely to be detected with atypical isolated red signals (p < 0.001), while patients with complex ALK rearrangements were more likely to be detected with atypical split red and green signals less than 2 signal diameters apart (p < 0.001). Our study highlights the reliability of NGS in the accurate detection of specific ALK fusion variants and concomitant mutations that are crucial for individualized treatment decisions in patients with lung cancer.

A Systematic Review of Companion Diagnostic Tests by Immunohistochemistry for the Screening of Alectinib-Treated Patients in ALK-Positive Non-Small Cell Lung Cancer

Companion diagnostic tests and targeted therapy changed the management of non-small cell lung cancer by diagnosing genetic modifications and enabling individualized treatment. The purpose of this systematic review is to assess the clinical applicability of companion diagnostic tests (IHC method) by comparing the effects of alectinib and crizotinib in patients with ALK-positive NSCLC. We searched for literature up to March 2022 in PubMed, Web of Science, Cochrane, and Google Scholar. The inclusion criteria were randomized controlled trials comparing the effectiveness of alectinib and crizotinib using an IHC-based companion diagnostic test. The primary outcome was progression-free survival (PFS). The secondary outcomes were objective response rate (ORR), duration of response (DOR), and overall survival (OS). PFS was longer in alectinib (68.4 [61.0, 75.9]) than crizotinib (48.7 [40.4, 56.9]). This indicated that alectinib had a superior efficacy to that of crizotinib (HR range 0.15–0.47). In all secondary outcomes, alectinib was better than crizotinib. Particularly for the ORR, the odds ratio (OR) confirmed that alectinib had a lower risk rate (OR: 2.21, [1.46–3.36], p = 0.0002, I² = 39%). Therefore, the companion diagnostic test (immunohistochemistry) is an effective test to determine whether to administer alectinib to ALK-positive NSCLC patients.

Too Sensitive or Just Right?

OBJECTIVES

To compare the performance of the rabbit monoclonal antihuman CD246 antibody (D5F3 clone) with the established ALK1 clone for immunohistochemical assessment of anaplastic large cell lymphoma (ALCL).

METHODS

Archival cases of ALCL (n = 27) were assessed immunohistochemically by use of ALK1 and D5F3 clones under standard Clinical Laboratory Improvement Amendments-compliant conditions. The intensity of cytoplasmic staining (0 = none; 1 = faint; 2 = moderate; 3+ = strong) and proportion of neoplastic cells (0%, <5%, 5%-50%, >50%) were evaluated and compared with clinical ALK break-apart fluorescence in situ hybridization (FISH) assays.

RESULTS

Nine ALCL specimens were positive for ALK expression by ALK1 staining (33%; 1 = 1+; 0 = 2+; 8 = 3+), while 14 were positive by D5F3 staining (48%; 3 = 1+; 1 = 2+; 10 = 3+). Across the cohort, D5F3 staining showed a significantly greater proportion of cells staining positive (P = .02) and greater intensity (P = .03). Of 3 cases positive for D5F3 only with FISH results, none showed rearrangements, although 1 showed copy number gains at the ALK locus in a subset of cells.

CONCLUSIONS

Overall, D5F3 showed greater stain intensity and proportion staining than ALK1 in ALK-positive ALCL cases, which is especially helpful in limited samples. Caution and consideration of orthogonal ALK testing types is recommended, especially for cases with weak or focal staining.

Molecular diagnosis in non-small-cell lung cancer: expert opinion on ALK and ROS1 testing

The effectiveness of targeted therapies with tyrosine kinase inhibitors in non-small-cell lung cancer (NSCLC) depends on the accurate determination of the genomic status of the tumour. For this reason, molecular analyses to detect genetic rearrangements in some genes (ie, ALK, ROS1, RET and NTRK) have become standard in patients with advanced disease. Since immunohistochemistry is easier to implement and interpret, it is normally used as the screening procedure, while fluorescence in situ hybridisation (FISH) is used to confirm the rearrangement and decide on ambiguous immunostainings. Although FISH is considered the most sensitive method for the detection of ALK and ROS1 rearrangements, the interpretation of results requires detailed guidelines. In this review, we discuss the various technologies available to evaluate ALK and ROS1 genomic rearrangements using these techniques. Other techniques such as real-time PCR and next-generation sequencing have been developed recently to evaluate ALK and ROS1 gene rearrangements, but some limitations prevent their full implementation in the clinical setting. Similarly, liquid biopsies have the potential to change the treatment of patients with advanced lung cancer, but further research is required before this technology can be applied in routine clinical practice. We discuss the technical requirements of laboratories in the light of quality assurance programmes. Finally, we review the recent updates made to the guidelines for the determination of molecular biomarkers in patients with NSCLC.

Methods for actionable gene fusion detection in lung cancer: now and in the future

Although gene fusions occur rarely in non-small-cell lung cancer (NSCLC) patients, they represent a relevant target in treatment decision algorithms. To date, immunohistochemistry and fluorescence in situ hybridization are the two principal methods used in clinical trials. However, using these methods in routine clinical practice is often impractical and time consuming because they can only analyze single genes and the quantity of tissue material is often insufficient. Thus, novel technologies, able to test multiple genes in a single run with minimal sample input, are being under investigation. Here, we discuss the utility of next-generation sequencing and nCounter technologies in detecting simultaneous gene fusions in NSCLC patients.

A novel break site of EML4-ALK report and a rare PRKAR1A-ALK report analyzed by different ALK detection platforms in non-small cell lung cancer patients

Background

detection of anaplastic lymphoma receptor tyrosine kinase gene (ALK) rearrangements in patients with non‐small‐cell lung cancer (NSCLC) has become a routine pathological diagnosis worldwide.

Methods

there are three major conventional diagnostic methods for ALK fusions: fluorescent in situ hybridization (FISH); immunohistochemistry (Ventana IHC (D5F3)); and polymerase chain reaction (PCR). Next‐generation sequencing (NGS) technology as is a new tool for ALK status detection with great potential. These four methods are highly consistent in detecting ALK status (coincidence rate >96%). However, discrepancies in ALK status have been found in some patients among these methods, which causes confusion for clinicians.

Results and conclusion

in this study, we analyzed two patients whose ALK statuses were not consistent using these four methods. We explored the potential reasons for deviation of the test results and found a novel EML4‐ALK break site, which had been not described previously.

Clinical utility of next-generation sequencing-based ctDNA testing for common and novel ALK fusions

OBJECTIVES

Liquid biopsy for plasma circulating tumor DNA (ctDNA) next-generation sequencing (NGS) can detect ALK fusions, though data on clinical utility of this technology in the real world is limited.

MATERIALS AND METHODS

Patients with lung cancer without known oncogenic drivers or who had acquired resistance to therapy (n = 736) underwent prospective plasma ctDNA NGS. A subset of this cohort (n = 497) also had tissue NGS. We evaluated ALK fusion detection, turnaround time (TAT), plasma and tissue concordance, matching to therapy, and treatment response.

RESULTS

ctDNA identified an ALK fusion in 21 patients (3%) with a variety of breakpoints and fusion partners, including EML4, CLTC, and PON1, a novel ALK fusion partner. TAT for ctDNA NGS was shorter than tissue NGS (10 vs. 20 days; p < 0.001). Among ALK fusions identified by ctDNA, 93% (13/14, 95% CI 66%-99%) were concordant with tissue evaluation. Among ALK fusions detected by tissue NGS, 54% (13/24, 95% CI 33%-74%) were concordant with plasma ctDNA. ctDNA matched patients to ALK-directed therapy with subsequent clinical response, including four patients matched on the basis of ctDNA results alone due to inadequate or delayed tissue testing. Serial ctDNA analysis detected MET amplification (n = 2) and ALK G1202R mutation (n = 2) as mechanisms of acquired resistance to ALK-directed therapy.

CONCLUSION

Our findings support a complementary role for ctDNA in detection of ALK fusions and other alterations at diagnosis and therapeutic resistance settings.

Screening for ROS1 fusions in patients with advanced non-small cell lung carcinomas using the VENTANA ROS1 (SP384) Rabbit Monoclonal Primary Antibody

Introduction: The development of several ROS1 inhibitors means that the importance of accurately identifying ROS1-positive lung cancer patients has never been greater. Therefore, it is crucial that ROS1 testing assays become more standardized.Areas covered: Based on primary literature, combined with personal diagnostic and research experience, this review provide a pragmatic update on the use of the recently released VENTANA ROS1 (SP384) Rabbit Monoclonal Primary Antibody.Expert opinion: This assay provides high sensitivity, so it is an excellent analytical option when screening for ROS1 fusions in patients with advanced non-small cell lung carcinomas.

Comparison of Next-Generation Sequencing and Ventana Immunohistochemistry in Detecting ALK Rearrangements and Predicting the Efficacy of First-Line Crizotinib in Patients with Advanced Non-Small Cell Lung Cancer

Introduction

Reliable diagnostic approaches to detect ALK rearrangement are critical for selecting patients eligible for crizotinib therapy. This study aimed to compare next-generation sequencing (NGS) and Ventana immunohistochemistry (IHC) in evaluating ALK rearrangements and evaluate their impact on first-line crizotinib efficacy.

Patients and Methods

A total of 472 NSCLC patients were identified as ALK-positive by NGS and/or IHC between March 2014 and February 2020. The concordance of ALK detection, overall response rate (ORR), and progression-free survival (PFS) were analyzed for 319 patients who received front-line crizotinib.

Results

First-line crizotinib (n=319) significantly prolonged PFS in comparison with chemotherapy (n=46; 12.0 vs 6.8 months; p<0.0001). Of the 76 crizotinib-treated patients whose ALK status was assessed by both NGS and IHC, 78.9% of the patients had concordant ALK status (NGS-positive/IHC-positive), 18.4% patients were NGS-positive but IHC-negative, and 2 patients were IHC-positive but NGS-negative. Different detection assays confer no statistical difference in ORR and PFS with first-line crizotinib. The ORR in NGS only, IHC only, and both NGS and IHC was 84.3%, 90.1%, and 88.1%, respectively, while PFS was 11.4, 13.0, and 11.0 months, respectively. The ORR in NGS-positive/IHC-positive and NGS-positive/IHC-negative patients was 85.4% and 92.8%, respectively. Compared to NGS-positive/IHC-positive patients, those with NGS-positive/IHC-negative results had a trend of shorter PFS but statistical significance was not reached (mPFS, 5.9 months vs 11.5 months, p=0.43).

Conclusion

Our results demonstrate that ALK status detected by NGS and/or IHC is reliable in identifying patients with ALK-positive NSCLC who will benefit from ALK inhibitor therapy.

Evaluation of a new diagnostic immunohistochemistry approach for ROS1 rearrangement in non-small cell lung cancer

BACKGROUND

ROS1 rearrangement is an oncogenic driver of non-small cell lung cancer (NSCLC). Accurate detection of ROS1 rearrangements in clinical tumor samples is vital. In this study, a new immunohistochemistry (IHC) monoclonal antibody (mAb) 1A1 assay was evaluated in patients with NSCLC.

METHODS

A cohort (cohort A) of 22 positive ROS1 reverse transcription-polymerase chain reaction (RT-PCR) samples were studied to evaluate the IHC-1A1 assay by comparing IHC-D4D6 mAb and another cohort (cohort B) of 178 consecutive cases to verify the assay by comparison using the RT-PCR method. IHC results with 2+ (H-score > 100) or 3+ staining was considered ROS1-positive.

RESULTS

In cohort A, ROS1 protein expression was evaluated in 22 samples by IHC-D4D6 and IHC-1A1 assays. For IHC-1A1, one patient was 1+ and 11 patients were 1+ for IHC-D4D6. ROS1 2-3+ was found in 36.4 % (8/22) of samples with IHC-D4D6 and 90.9 % (20/22) with IHC-1A1.The mean H-score of the 1A1 ROS1 2-3+ cases was 203.5. With the D4D6 clone, the mean H-score of the D4D6 ROS1 2∼3+ cases was 182.5. In the 178 NSCLC patients in cohort B, ROS1 rearrangement was detected with IHC and RT-PCR assays. Two patients had tumors with ROS1 IHC-1A1 3+ and one patient was IHC-1A1 2+. Among the three patients, two were confirmed to have ROS1 rearrangement by RT-PCR. None of the 175 ROS1 IHC-1A1 0-1+ samples were ROS1-positive by RT-PCR.

CONCLUSIONS

The results showed that the new IHC-1A1 ROS1 clone is a sensitive preliminary method and may be another excellent screening method in addition to the original IHC detection method to detect ROS1 gene rearrangements.

[Updated guidelines for predictive biomarker testing in advanced non-small-cell lung cancer: A National Consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology]

In 2011, the Spanish Society of Medical Oncology (SEOM) and the Spanish Society of Pathology (SEAP) initiated a joint project to establish guidelines for biomarker testing in patients with advanced non-small-cell lung cancer based on the information available at the time. As this field is constantly evolving, these guidelines were updated in 2012 and 2015 and now in 2019. Current evidence suggests it should be mandatory to test all patients with this kind of advanced lung cancer for EGFR and BRAF mutations, ALK and ROS1 rearrangements and PD-L1 expression. The growing need to study other emerging biomarkers has promoted the routine use of massive sequencing (next-generation sequencing, NGS). However, the coordination of every professional involved and the prioritisation of the most suitable tests and technologies for each case remain a challenge.

Clinical evaluation of the effectiveness of fusion-induced asymmetric transcription assay-based reverse transcription droplet digital PCR for ALK detection in formalin-fixed paraffin-embedded samples from lung cancer

BACKGROUND

Accurate detection of anaplastic lymphoma kinase (ALK) rearrangement is the prerequisite for anti-ALK therapy for the patient with non-small cell lung cancer (NSCLC). Fusion-induced asymmetric transcription assay (FIATA)-based reverse transcription droplet digital PCR (RT-ddPCR) was developed and performed for ALK status survey in NSCLC samples.

METHODS

A total of 269 cases of formalin-fixed paraffin-embedded (FFPE) specimens from NSCLC, in which ALK status was confirmed by both fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC), were analyzed by FIATA-based RT-ddPCR.

RESULTS

In the ALK-positive group, the 3' ALK transcript copies range was 336.6-107 955.4, and the R3 [(the ratio of the 3' ALK transcript copy numbers to the internal reference gene transcript copy numbers) × 100] was 17.23-672.77. In the ALK-negative group, the 3' ALK transcript copies range was 3.7-1370.6, and the R3 range was 0.10-15.57. The lowest R3 level in the ALK-positive group was significantly higher than the highest R3 level in the ALK-negative group. A positive correlation between the proportion of cancer cells in the tissue section and ALK RNA expression level (R3) was found (P < 0.05). There was no relationship between the percentage of FISH positive cells or FISH positive signal patterns and R3 level of the ALK gene. Compared with FISH and IHC, the clinical sensitivity and specificity of FIATA-based RT-ddPCR for ALK detection were 100%, respectively.

CONCLUSIONS

An absolute quantitative FIATA-based RT-ddPCR was developed and validated for ALK fusion detection in NSCLC. This method can rapidly, accurately, and objectively classify ALK types and help with individual therapy.

Genomic Profiling Reveals Synchronous Bilateral Lung Adenocarcinomas With Distinct Driver Alterations of EML4-ALK or TPM3-ROS1 Fusion: A Case Report

Background:ALK and ROS1 rearrangement accounts for 3–6% and 1–3% of non-small cell lung cancers, respectively, while coexistence of them in the same patient is extremely rare. Only three cases have ever been reported with concurrent ALK/ROS1 fusions in the same tumor indicating tumor heterogeneity. Therefore, comprehensive genetic profiling via next-generation sequencing (NGS) is needed to provide fully molecular diagnosis.

Case Presentation: A 50-year old Chinese female with resectable stage IB bilateral lung adenocarcinomas (ADCs) harbored EML4 exon 6-ALK exon 19 and TPM3 exon 8-ROS1 exon 35 fusions in the right lower and the left upper tumors, respectively, identified by clinical NGS test targeting 425 cancer-relevant genes. The results were further confirmed at RNA level using RNA-seq. Genomic evolution analysis reveals that these bilateral tumors are synchronous multiple primary lung cancers with no shared somatic alterations for both genes and arm-level copy number variations (CNVs). No recurrence was observed during 12 months of post-surgery follow-up.

Conclusions: Our case is the first report of concurrent ALK/ROS1 fusions as distinct driver events of synchronous multiple primary lung cancers, and highlights the importance of individual genetic testing for each of the multiple primary tumors for fully molecular diagnosis and precise treatment decision-making.

Translating Systems Medicine Into Clinical Practice: Examples From Pulmonary Medicine With Genetic Disorders, Infections, Inflammations, Cancer Genesis, and Treatment Implication of Molecular Alterations in Non-small-cell Lung Cancers and Personalized Medicine

Non-small-cell lung cancers (NSCLC) represent 85% of all lung cancers, with adenocarcinoma as the most common subtype. Since the 2000's, the discovery of molecular alterations including epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangements together with the development of specific tyrosine kinase inhibitors (TKIs) has facilitated the development of personalized medicine in the management of this disease. This review focuses on the biology of molecular alterations in NSCLC as well as the diagnostic tools and therapeutic alternatives available for each targetable alteration. Rapid and sensitive methods are essential to detect gene alterations, using tumor tissue biopsies or liquid biopsies. Massive parallel sequencing or Next Generation Sequencing (NGS) allows to simultaneously analyze numerous genes from relatively low amounts of DNA. The detection of oncogenic fusions can be conducted using fluorescence in situ hybridization, reverse-transcription polymerase chain reaction, immunohistochemistry, or NGS. EGFR mutations, ALK and ROS1 rearrangements, MET (MET proto-oncogenereceptor tyrosine kinase), BRAF (B-Raf proto-oncogen serine/threonine kinase), NTRK (neurotrophic tropomyosin receptor kinase), and RET (ret proto-oncogene) alterations are described with their respective TKIs, either already authorized or still in development. We have herein paid particular attention to the mechanisms of resistance to EGFR and ALK-TKI. As a wealth of diagnostic tools and personalized treatments are currently under development, a close collaboration between molecular biologists, pathologists, and oncologists is crucial.

Targeted RNA-sequencing assays: a step forward compared to FISH and IHC techniques?

Introduction

ALK and ROS1 rearrangements are molecular targets of several tyrosine kinase inhibitors. RNA‐sequencing approaches are regarded as the new standard for fusion gene detection, representing an alternative to standard immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) techniques.

Patients and Methods

We aimed to compare two recent amplicon‐based RNA‐sequencing techniques: FusionPlex^® Alk Ret Ros1 v2 Kit (Archer^®) with FHS‐003Z‐12—Human Lung Cancer Panel (Qiagen^®) and assessed the accuracy of the data for therapy management. Thirty‐seven formalin‐fixed paraffin‐embedded non‐small cell carcinoma (NSCC) lesions initially explored by IHC and FISH were selected for RNA‐sequencing analysis.

Results

Qiagen^® and Archer^® kits produced similar results and correctly identified 85.1% (23/27) and 81.5% (22/27) of IHC/FISH ALK‐ and ROS1‐positive samples, respectively, and 100% (6/6) of the negative samples. With regard to the ambiguous IHC‐positive/FISH‐negative cases, RNA‐sequencing confirmed 75% (3/4) of the FISH conclusion. Although not statistically significant, patients with common EML4‐ALK variants presented shorter overall survival and progression‐free survival compared with patients harboring rare variants.

Conclusion

Our findings assessed the implementation of RNA‐sequencing approaches to explore ALK and ROS1 rearrangements from formalin‐fixed paraffin‐embedded samples. We highlighted the similarities between Qiagen^® and Archer^® kits in terms of handling time, cost, and outcomes. We confirmed the feasibility of molecular testing in routine organization and its possible use not only as an alternative for standard IHC and FISH techniques, but as a supplementary technique helping to classify discrepant cases.

Updated guidelines for predictive biomarker testing in advanced non-small-cell lung cancer: a National Consensus of the Spanish Society of Pathology and the Spanish Society of Medical Oncology

In 2011 the Spanish Society of Medical Oncology (SEOM) and the Spanish Society of Pathology (SEAP) started a joint project to establish guidelines on biomarker testing in patients with advanced non-small-cell lung cancer (NSCLC) based on current evidence. As this field is constantly evolving, these guidelines have been updated, previously in 2012 and 2015 and now in 2019. Current evidence suggests that the mandatory tests to conduct in all patients with advanced NSCLC are for EGFR and BRAF mutations, ALK and ROS1 rearrangements and PD-L1 expression. The growing need to study other emerging biomarkers has promoted the routine use of massive sequencing (next-generation sequencing, NGS). The coordination of every professional involved and the prioritisation of the most suitable tests and technologies for each case remains a challenge.

Comment on "ALK is a therapeutic target for lethal sepsis"

Physiologically relevant ALK (anaplastic lymphoma kinase) expression was not detected in human and mouse monocytes and macrophages, suggesting that the effects of bioactive compounds on stimulator of interferon genes (STING) activation may not depend on ALK.

Fluorescence in Situ Hybridization (FISH) for Detecting Anaplastic Lymphoma Kinase (ALK) Rearrangement in Lung Cancer: Clinically Relevant Technical Aspects

In 2011, the Vysis Break Apart ALK fluorescence in situ hybridization (FISH) assay was approved by the United States Food and Drug Administration as a companion diagnostic for detecting ALK rearrangement in lung cancer patients who may benefit from treatment of tyrosine kinase inhibitor therapy. This assay is the current “gold standard”. According to updated ALK testing guidelines from the College of American Pathologists, the International Association for the Study of Lung Cancer and the Association for Molecular Pathology published in 2018, ALK immunohistochemistry is formally an alternative to ALK FISH, and simultaneous detection of multiple hot spots, including, at least, ALK, ROS1, RET, MET, ERBB2, BRAF and KRAS genes is also recommended while performing next generation sequencing (NGS)-based testing. Therefore, ALK status in a specimen can be tested by different methods and platforms, even in the same institution or laboratory. In this review, we discuss several clinically relevant technical aspects of ALK FISH, including pros and cons of the unique two-step (50- to 100-cell) analysis approach employed in the Vysis Break Apart ALK FISH assay, including: the preset cutoff value of ≥15% for a positive result; technical aspects and biology of discordant results obtained by different methods; and incidental findings, such as ALK copy number gain or amplification and co-existent driver mutations. These issues have practical implications for ALK testing in the clinical laboratory following the updated guidelines.

Comparison of ALK detection by FISH, IHC and NGS to predict benefit from crizotinib in advanced non-small-cell lung cancer

PURPOSE

Anaplastic lymphoma kinase (ALK) is now a validated kinase target in non-small cell lung cancer (NSCLC). We implemented three ALK laboratory methodologies: fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) and next-generation sequencing (NGS) to detect EML4-ALK fusions and compared the predictive value for Crizotinib efficacy in ALK-positive patients.

METHODS

55 ALK positive patients confirmed by at least one method were enrolled in the present study, of whom 45 cases were assessed by FISH, IHC and NGS concurrently, and another 10 cases only received IHC and NGS assessment for ALK status.

RESULTS

IHC presented the uppermost positive rate (94.5%), followed by NGS (92.7%) and FISH(82.4%), among which IHC and NGS had the highest concordance rate of 87.3%. No difference was detected in ORR, DCR and PFS of ALK positive cases defined in three groups. Notably, NGS positive patients were correlated with a higher DCR and longer PFS compared to NGS negative cases (P = 0.02 and P = 0.09), while FISH and IHC status were not distinguishing in predicting the outcome of Crizotinib. TP53 concurrent mutation might reduce responsiveness to Crizotinib and worsen prognosis in ALK-rearranged NSCLC.

CONCLUSION

FISH present a certain false-negative rate although considered the gold standard. Ventana-D5F3 IHC is qualified as a screening tool, while NGS positive may predict clinical benefit of Crizotinib more accurately, allowing efficient test for specific variants and concurrent genomic alterations.

Immunohistochemistry-Enabled Precision Medicine

Immunohistochemistry (IHC) can be applied to diagnostic aspects of pathologic examination to provide aid in assignment of lineage and histologic type of cancer. Increasingly, however, IHC is widely used to provide prognostic and predictive (theranostic) information about the neoplastic disease. A refinement of theranostic application of IHC can be seen in the use of "genomic probing" where antibody staining results are directly correlated with an underlying genetic alteration in the tumor (somatic mutations) and/or the patient (germline constitution). All these aspects of IHC find their best use in guiding the oncologists in the optimal use of therapy for the patients.

Genomic heterogeneity of ALK fusion breakpoints in non-small-cell lung cancer

In lung adenocarcinoma, canonical EML4-ALK inversion results in a fusion protein with a constitutively active ALK kinase domain. Evidence of ALK rearrangement occurs in a minority (2-7%) of lung adenocarcinoma, and only ~60% of these patients will respond to targeted ALK inhibition by drugs such as crizotinib and ceritinib. Clinically, targeted anti-ALK therapy is often initiated based on evidence of an ALK genomic rearrangement detected by fluorescence in situ hybridization (FISH) of interphase cells in formalin-fixed, paraffin-embedded tissue sections. At the genomic level, however, ALK rearrangements are heterogeneous, with multiple potential breakpoints in EML4, and alternate fusion partners. Using next-generation sequencing of DNA and RNA together with ALK immunohistochemistry, we comprehensively characterized genomic breakpoints in 33 FISH-positive lung adenocarcinomas. Of these 33 cases, 29 (88%) had detectable DNA level ALK rearrangements involving EML4, KIF5B, or non-canonical partners including ASXL2, ATP6V1B1, PRKAR1A, and SPDYA. A subset of 12 cases had material available for RNA-Seq. Of these, eight of eight (100%) cases with DNA rearrangements showed ALK fusion transcripts from RNA-Seq; three of four cases (75%) without detectable DNA rearrangements were similarly negative by RNA-Seq, and one case was positive by RNA-Seq but negative by DNA next-generation sequencing. By immunohistochemistry, 17 of 19 (89%) tested cases were clearly positive for ALK protein expression; the remaining cases had no detectable DNA level rearrangement or had a non-canonical rearrangement not predicted to form a fusion protein. Survival analysis of patients treated with targeted ALK inhibitors demonstrates a significant difference in mean survival between patients with next-generation sequencing confirmed EML4-ALK rearrangements, and those without (20.6 months vs 5.4 months, P<0.01). Together, these data demonstrate abundant genomic heterogeneity among ALK-rearranged lung adenocarcinoma, which may account for differences in treatment response with targeted ALK inhibitors.

ALK-rearrangement in non-small-cell lung cancer (NSCLC)

The ALK gene encodes a transmembrane tyrosine kinase receptor. ALK is physiologically expressed in the nervous system during embryogenesis, but its expression decreases postnatally. ALK first emerged in the field of oncology in 1994 when it was identified to fuse to NPM1 in anaplastic large-cell lymphoma. Since then, ALK has been associated with other types of cancers, including non-small-cell lung cancer (NSCLC). More than 19 different ALK fusion partners have been discovered in NSCLC, including EML4, KIF5B, KLC1, and TPR. Most of these ALK fusions in NSCLC patients respond well to the ALK inhibitor, crizotinib. In this paper, we reviewed fusion partner genes with ALK, detection methods for ALK-rearrangement (ALK-R), and the ALK-tyrosine kinase inhibitor, crizotinib, used in NSCLC patients.

Big Potential from Small Agents: Nanoparticles for Imaging-Based Companion Diagnostics

The importance of medical imaging in the diagnosis and monitoring of cancer cannot be overstated. As personalized cancer treatments are gaining popularity, a need for more advanced imaging techniques has grown significantly. Nanoparticles are uniquely suited to fill this void, not only as imaging contrast agents but also as companion diagnostics. This review provides an overview of many ways nanoparticle imaging agents have contributed to cancer imaging, both preclinically and in the clinic, as well as charting future directions in companion diagnostics. We conclude that, while nanoparticle-based imaging agents are not without considerable scientific and developmental challenges, they enable enhanced imaging in nearly every modality, hold potential as in vivo companion diagnostics, and offer precise cancer treatment and maximize intervention efficacy.

Any Place for Immunohistochemistry within the Predictive Biomarkers of Treatment in Lung Cancer Patients?

The identification of certain genomic alterations (EGFR, ALK, ROS1, BRAF) or immunological markers (PD-L1) in tissues or cells has led to targeted treatment for patients presenting with late stage or metastatic lung cancer. These biomarkers can be detected by immunohistochemistry (IHC) and/or by molecular biology (MB) techniques. These approaches are often complementary but depending on, the quantity and quality of the biological material, the urgency to get the results, the access to technological platforms, the financial resources and the expertise of the team, the choice of the approach can be questioned. The possibility of detecting simultaneously several molecular targets, and of analyzing the degree of tumor mutation burden and of the micro-satellite instability, as well as the recent requirement to quantify the expression of PD-L1 in tumor cells, has led to case by case development of algorithms and international recommendations, which depend on the quality and quantity of biological samples. This review will highlight the different predictive biomarkers detected by IHC for treatment of lung cancer as well as the present advantages and limitations of this approach. A number of perspectives will be considered.

Tracking the Evolution of Resistance to ALK Tyrosine Kinase Inhibitors through Longitudinal Analysis of Circulating Tumor DNA

Purpose

ALK rearrangements predict for sensitivity to ALK tyrosine kinase inhibitors (TKIs). However, responses to ALK TKIs are generally short-lived. Serial molecular analysis is an informative strategy for identifying genetic mediators of resistance. Although multiple studies support the clinical benefits of repeat tissue sampling, the clinical utility of longitudinal circulating tumor DNA analysis has not been established in ALK-positive lung cancer.

Methods

Using a 566-gene hybrid-capture next-generation sequencing (NGS) assay, we performed longitudinal analysis of plasma specimens from 22 ALK-positive patients with acquired resistance to ALK TKIs to track the evolution of resistance during treatment. To determine tissue-plasma concordance, we compared plasma findings to results of repeat biopsies.

Results

At progression, we detected an ALK fusion in plasma from 19 (86%) of 22 patients, and identified ALK resistance mutations in plasma specimens from 11 (50%) patients. There was 100% agreement between tissue- and plasma-detected ALK fusions. Among 16 cases where contemporaneous plasma and tissue specimens were available, we observed 100% concordance between ALK mutation calls. ALK mutations emerged and disappeared during treatment with sequential ALK TKIs, suggesting that plasma mutation profiles were dependent on the specific TKI administered. ALK G1202R, the most frequent plasma mutation detected after progression on a second-generation TKI, was consistently suppressed during treatment with lorlatinib.

Conclusions

Plasma genotyping by NGS is an effective method for detecting ALK fusions and ALK mutations in patients progressing on ALK TKIs. The correlation between plasma ALK mutations and response to distinct ALK TKIs highlights the potential for plasma analysis to guide selection of ALK-directed therapies.

The applications of liquid biopsy in resistance surveillance of anaplastic lymphoma kinase inhibitor

With the clinical promotion of precision medicine and individualized medical care, molecular targeted medicine has been used to treat non-small cell lung cancer (NSCLC) patients and proved to be significantly effective. Anaplastic lymphoma kinase (ALK) inhibitor is one of the most important specific therapeutic agents for patients with ALK-positive NSCLC. It can extend the survival of patients. However, resistance to the ALK inhibitor inevitably develops in the application process. So, the real-time resistance surveillance is particularly important, and liquid biopsy is one of the most potential inspection methods. Circulating tumor cells, circulating free tumor DNA and exosome in body fluid are used as the main detection biomarkers to reflect the occurrence of resistance in real time through sequencing or counting and then to guide the follow-up treatment.

Anaplastic Lymphoma Kinase Testing: IHC vs. FISH vs. NGS

OPINION STATEMENT

Personalized targeted therapy has emerged as a promising strategy in lung cancer treatment, with current attention focused on elucidation and detection of oncogenic drivers responsible for tumor initiation and maintenance and development of drug resistance. In lung cancer, several oncogenic drivers have been reported, triggering the application of tyrosine kinase inhibitors (TKIs) to target these dysfunctional genes. The anaplastic lymphoma kinase (ALK) rearrangement is responsible for about 4-7% of all non-small cell lung cancers (NSCLCs) and perhaps as high as a third in specific patient populations such as younger, male, non-smokers with advanced stage, epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene (KRAS) wild type, and signet ring cell adenocarcinoma with abundant intracytoplasmic mucin. The selection of patients based on their ALK status is vital on account of the high response rates with the ALK-targeted agents in this subset of patients. Standardization and validation of ALK rearrangement detection methods is essential for accurate and reproducible results. There are currently three detection methods widely available in clinical practice, including fluorescent in situ hybridization (FISH), immunohistochemistry (IHC), and polymerase chain reaction (PCR)-based next generation sequencing (NGS) technology. However, the choice of diagnostic methodology for ALK rearrangement detection in clinical practice remains a matter of debate. With accumulating data enumerating the advantages and disadvantages of each of the three methods, combining more than one testing method for ALK fusion detection may be beneficial for patients. In this review, we will discuss the current methods used in ALK rearrangement detection with emphasis on their key advantages and disadvantages.

Addressing the challenges of applying precision oncology

Precision oncology is described as the matching of the most accurate and effective treatments with the individual cancer patient. Identification of important gene mutations, such as BRCA1/2 that drive carcinogenesis, helped pave the way for precision diagnosis in cancer. Oncoproteins and their signaling pathways have been extensively studied, leading to the development of target-based precision therapies against several types of cancers. Although many challenges exist that could hinder the success of precision oncology, cutting-edge tools for precision diagnosis and precision therapy will assist in overcoming many of these difficulties. Based on the continued rapid progression of genomic analysis, drug development, and clinical trial design, precision oncology will ultimately become the standard of care in cancer therapeutics.

Performance of a RT-PCR Assay in Comparison to FISH and Immunohistochemistry for the Detection of ALK in Non-Small Cell Lung Cancer

Patients with lung cancers harboring an activating anaplastic lymphoma kinase (ALK) rearrangement respond favorably to ALK inhibitor therapy. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) are validated and widely used screening tests for ALK rearrangements but both methods have limitations. The ALK RGQ RT-PCR Kit (RT-PCR) is a single tube quantitative real-time PCR assay for high throughput and automated interpretation of ALK expression. In this study, we performed a direct comparison of formalin-fixed paraffin-embedded (FFPE) lung cancer specimens using all three ALK detection methods. The RT-PCR test (diagnostic cut-off ΔC_t of ≤8) was shown to be highly sensitive (100%) when compared to FISH and IHC. Sequencing of RNA detected full-length ALK transcripts or EML4-ALK and KIF5B-ALK fusion variants in discordant cases in which ALK expression was detected by the ALK RT-PCR test but negative by FISH and IHC. The overall specificity of the RT-PCR test for the detection of ALK in cases without full-length ALK expression was 94% in comparison to FISH and sequencing. These data support the ALK RT-PCR test as a highly efficient and reliable diagnostic screening approach to identify patients with non-small cell lung cancer whose tumors are driven by oncogenic ALK.