Role of cytology in the management of non-small-cell lung cancer

Detailed procedure and clinical application overview of rapid on-site evaluation in diagnostic interventional pulmonology

Diagnostic interventional pulmonology is widely accepted as a minimally invasive, highly accurate procedure for diagnosing lung cancer, more drug-resistant pathogen infections of lower respiratory tract, and critical respiratory diseases. The efficiency of interventional diagnostics depends on quite a few factors, including size and the anatomic location of lymph nodes, number of biopsy sites and complications rate, characteristics of the lesion, and underlying disease. Specifically, the application of rapid on-site evaluation (ROSE) may avoid additional sampling without compromising diagnostic yield with a preliminary evaluation for adequate diagnostic material and thus reduce the complication rate. In this review article we aimed at elaborate the technical details, clinical roles, and technological progress of ROSE in diagnostic interventional pulmonology, highlighting the importance of ROSE in diagnostic interventional pulmonology. We finally pointed out that it will be a tendency for a pulmonologist, to undergo a short yet intensive training and perform ROSE in diagnostic interventional pulmonology.

The role of endobronchial ultrasound transbronchial needle aspiration for programmed death ligand 1 testing and next generation sequencing in advanced non-small cell lung cancer

Guidelines recommend testing for driver mutations and programmed death ligand 1 (PD-L1) expression at the time of initial diagnosis and during disease progression to help determine prognosis and initiate personalized therapy. In this article we review the updated literature and techniques of endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) in obtaining adequate tissue for molecular analysis by using next-generation sequencing (NGS) and for assessing PD-L1 expression through immunohistochemistry.

Clinical performance of endobronchial ultrasound-guided transbronchial needle aspiration for assessing programmed death ligand-1 expression in nonsmall cell lung cancer

BACKGROUND

Pembrolizumab was recently approved as a first line agent for metastatic NSCLC in patients with high programmed death-ligand 1 (PD-L1) expression.

OBJECTIVES

Since a significant portion of lung cancer is diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS TBNA); there is a need for PD-L1 testing in these specimens. However, to date few studies have evaluated performance of cytology specimens from EBUS TBNA for PD-L1 analysis.

METHODS

Patients who had a diagnosis of NSCLC and in whom ancillary testing, i.e., next generation sequencing (NGS), anaplastic lymphoma kinase (ALK), and PD-L1 expression was requested between January and May 2017 were reviewed.

RESULTS

Fifty of the 112 patients reviewed had the diagnosis of NSCLC for which ancillary testing was requested. Twelve patients (24%) had squamous cell carcinoma, twenty-seven had adenocarcinoma (54%), five had NSCLC favor adenocarcinoma (10%), two had NSCLC favor squamous cell cancer (4%), and four had NSCLC not otherwise specified (NOS) (8%). Size of the lymph nodes or lesion sampled ranged from 10 to 50 mm. Four (8%) patients had insufficient number of tumor cells in the cell block for any of the ancillary molecular testing. Forty-one (82%) patients had an adequate sample for all three ancillary tests. Satisfactory results for PD-L1 expression for all cases was 86% with 14 (32%) patients having levels of PD-L1 expression >50%.

CONCLUSION

EBUS TBNA is effective and has a high proportion of satisfactory results for testing PD-L1 expression on tumor cells in addition to NGS and ALK FISH.

Feasibility of Endobronchial Ultrasound-guided Transbronchial Needle Aspiration Cytology Specimens for Next Generation Sequencing in Non-small-cell Lung Cancer

INTRODUCTION

Next generation sequencing (NGS) testing of lung cancer is recommended by guidelines, and endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) often provides the only material available for testing. Previous studies have demonstrated successful NGS testing on cell block samples obtained by EBUS; however, cytology smears provide a more reliable sample with better DNA quality for testing. In this study, we aimed to determine the success rate of OncoScreen (50 gene) and OncoPlus (1213 gene) panel NGS testing of cytology samples obtained by EBUS utilizing 22- and 25-gauge needles.

METHODS

Fifty-four patients underwent EBUS-TBNA of lung cancer for which NGS testing was requested. Data was analyzed for needle gauge, cytologic assessment, NGS test success, and sample type (cytology smear or cell block) used for testing.

RESULTS

Eighty-five NGS tests were ordered on 54 samples. Overall, 95.3% of samples had successful testing. OncoScreen and OncoPlus panels were successful 98.0% and 91.4% of the time, respectively. Cytology smears provided testing material for 85% of the tests. OncoScreen testing was successful in 97.5% and 100% of the 22- and 25-gauge samples, respectively (P = 1.00). OncoPlus testing was successful in 91.3% and 100% of the 22- and 25-gauge samples, respectively (P = 1.00).

CONCLUSIONS

NGS can be reliably performed on cytology smears obtained from EBUS-TBNA. The size of the needle does not seem to affect the success rate of small or large panel NGS tests.

Intraoperative fine needle aspirations - diagnosis and typing of lung cancer in small biopsies: challenges and limitations

Background

Due to therapeutic implications with regard to both efficiency and safety of chemotherapy agents it is important to differentiate between subtypes of NSCLC. Up to today we experience a continuous reservation regarding the use of fine needle aspiration cytology. The aim of the present study is to estimate the value of cytologic criteria for lung cancer typing on small biopsies independent from all possible technique failures.

Methods

Between January 1997 and December 2008 760 intraoperative FNAC- (fine needle aspiration cytology) specimens from 702 patients have been examined. Cytologic evaluation and immediate communication of results to the surgeons followed. Afterwards, intraoperative cytologic findings were compared with final histologic diagnoses of the resected specimens.

Results

Intraoperative cytologic analysis yielded a sensitivity of 94.8 %, a specificity of 98.8 %. An overall positive predictive value of 99.8 % with respect to final histologic analysis of primary lung cancer was achieved. The highest value could be reached for adenocarcinomas, followed by carcinoids and squamous cell carcinomas.

Conclusions

Lung cancer typing according to cytologic criteria is feasible and accurate as well as comparable with results of histologic analysis on small specimens. Herewith, clinicians can come up to the increasing demands on minimally invasive harvested specimens with regard to therapeutic implications.

Utility of immunochemistry in cytology

Background:

The role played by cytology in primary diagnosis is undeniable. With improved management protocols and targeted therapy, the need for accurate diagnosis has become mandatory. Immunochemistry and molecular techniques are increasingly being used on limited tissue samples.

Aims:

This study was conducted to find out the impact of immunocytochemistry (ICC) on cytology material in cytology practice.

Materials and Methods:

Immunochemistry was done on alcohol-fixed smears and cell-block preparations. It was done with i6000 BioGenex autostainer using BioGenex reagents.

Results:

A total of 148 cases occurring over a period of 3 years (September 2010-June 2013) were analyzed. Staining was done on cytology smears in 77 cases and on cell-block sections in 71 cases. ICC helped in diagnosis in 8 cases, confirmed the diagnosis in 26 cases, helped in subtyping in 60 cases, and helped in prognostication in 6 cases. ICC has altered the diagnosis in two cases. It was noncontributory in 43 cases, and the material was inadequate in three cases.

Conclusion:

In 102 cases (69%), ICC proved to be a useful adjunct in the diagnosis and prognostication; hence, its use is recommended in practice to aid in cytology services.

Role of rapid on-site evaluation with cyto-histopathological correlation in diagnosis of lung lesion

Aim:

This study was conducted to assess the role of cytology in the diagnosis of lung lesions and to compare it with histopathology. It was also intended to evaluate the role of rapid on site evaluation (ROSE) as an adjunct to cytological diagnosis of lung lesions.

Materials and Methods:

The study included all the cases of lung lesions, which were diagnosed on cytology followed by histopathology over a period of 2½ years along with ROSE, wherever possible.

Results:

Cytology was done in total 782 cases of various lung lesions and of this cyto-histopathological correlation was available in 215 cases. ROSE was done in 93.4% of total cases and smears were considered on the site adequate in the first pass in 68.1% cases and in second pass adequacy increased to 93.4%. The diagnostic accuracy of cytology was 75.3%, and that of histology was 86.9% in the diagnosis of lung lesions. The diagnostic accuracy of cytology for squamous cell carcinoma (94.4%) and adenocarcinoma (96.5%) was higher than that of histology.

Conclusion:

Cytology is comparable to histology in the diagnosis of lung lesions and may even outperform biopsy in lung tumor diagnosis. The advantages of cytology may be further added by better sampling and preanalytical assessment for adequate diagnostic material and ROSE has proved to be an important, easy and cost effective adjunct in this regard. A multidisciplinary approach involving pulmonologist, radiologist and cytopathologist with ROSE, followed by vigilant morphological examination may increase diagnostic utility of cytology for lung lesions.

Characterization of endoscopic ultrasound fine-needle aspiration cytology by targeted next-generation sequencing and theranostic potential

Determination of tumor genetic architecture based on tissue analysis yields important information on signaling pathways involved in cancer pathogenesis and plays a growing role in choosing the optimal medical management of malignancies. Specifically, the advent of next-generation sequencing has led to a rapidly evolving era of relatively inexpensive, high-throughput DNA sequencing of tumors. One such example is multiplexed tumor genotyping (ie, panel testing) of more than 2800 mutations across 50 commonly mutated cancer-associated genes. This resulting mutational landscape shows medically actionable pathogenic alterations to optimize antitumor therapy. We recently assessed the performance and outcome of targeted next-generation sequencing with archived endoscopic ultrasound fine-needle aspirates across a broad range of primary and metastatic sites with encouraging accuracy. As a result, endoscopic ultrasound has the potential to move from a test for diagnosis or confirmation of malignancy, to one in which it could facilitate the personalization of cancer-directed therapy.

Five Top Stories in Cytopathology

Context.—Cytology relies heavily on morphology to make diagnoses, and morphologic criteria have not changed much in recent years. The field is being shaped predominantly by new techniques for imaging and for acquiring and processing samples, advances in molecular diagnosis and therapeutics, and regulatory issues.

Objective.—To review the importance of classical morphology in the future of cytopathology, to identify areas in which cytology is expanding or contracting in its scope, and to identify factors that are shaping the field.

Data Sources.—Literature review.

Conclusions.—Five stories paint a picture in which classical cytomorphology will continue to have essential importance, both for diagnosis and for improving our understanding of cancer biology. New endoscopy and imaging techniques are replacing surgical biopsies with cytology samples. New molecularly targeted therapies offer a chance for cytology to play a major role, but they pose new challenges. New molecular tests have the potential to synergize with, but not replace, morphologic interpretation of thyroid fine-needle aspirations. Ultrasound-guided fine-needle aspiration performed by cytopathologists is opening a new field of “interventional cytopathology” with unique value. For the productive evolution of the field, it will be important for cytopathologists to play an active role in clinical trials that document the ability of cytology to achieve cost-effective health care outcomes.

From targets to targeted therapies and molecular profiling in non-small cell lung carcinoma

Although tumor molecular-profile-directed therapy appears promising in early clinical studies, there are many practical challenges to its successful clinical application in non-small-cell lung cancer (NSCLC). These challenges may be broadly classified as those relating to tumor (heterogeneity), tissue (acquisition and processing), testing (assays for molecular profiling) and trials (clinical evaluation of molecular markers and drugs). Strategies to overcome these challenges include (i) understanding the biological basis of tumor heterogeneity and of carcinogenesis in the large subset of patients with no currently evident driver events; (ii) technological advances in minimally invasive acquisition of tumor and next-generation sequencing (NGS) which would enable single-platform analysis of molecular alterations in limited tissue at a reasonable turnaround time (TAT); (iii) deliberation in early stages of drug development as well as clinical trial design to identify, validate and assess the clinical utility of biomarkers in conjunction with drugs and (iv) collaboration to improve understanding of and accrual to trials enrolling patients with rare molecular alterations.

Epidermal growth factor receptor and Kras gene expression: reliability of mutational analysis on cytological samples

Epidermal growth factor receptor (EGFR) and Kras gene mutations are crucial for discriminating patients responsive to anti-EGFR drugs in non-small cell lung cancer (NSCLC) and colorectal cancer (CRC), respectively. The majority of NSCLCs come to clinical attention at an advanced stage when surgery is no longer recommended and a considerable number of them are diagnosed by cytology only. A large number of metastatic CRCs are also diagnosed by imaging and minimally invasive techniques such as fine-needle aspiration biopsy. Here, we report our experience in the mutation analysis of EGFR and Kras on cytological material obtained from superficial and deep lesions of NSCLC and CRC. Our series included 63 cytological specimens from primary or metastatic lesions of 42 NSCLCs and 21 CRCs. The cytological material was adequate for the mutation analysis in 39/42 (93%) NSCLCs and in 20/21(95%) CRCs. EGFR and Kras mutations were found in 9 (23%) and 9 (23%) NSCLC cases, respectively. Kras mutations were found in 9/20 (45%) CRC specimens. Histological samples from the primary tumors were available in 9/42 NSCLCs and in 17/21 CRCs. The agreement of EGFR and Kras mutational status in cytological vs. histological samples was 100% for NSCLC and 88% for CRC. Our results suggest that standard cytology provides adequate material for the assessment of EGFR and Kras mutational status in NSCLC and CRC patients and could be specifically indicated in patients not eligible for surgery but candidate to anti-EGFR therapy.

Suitability of endobronchial ultrasound-guided transbronchial needle aspiration specimens for subtyping and genotyping of non-small cell lung cancer: a multicenter study of 774 patients

RATIONALE

The current management of advanced non-small cell lung cancer (NSCLC) requires differentiation between squamous and nonsquamous subtypes as well as epidermal growth factor receptor (EGFR) mutation status. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is increasingly used for the diagnosis and staging of lung cancer. However, it is unclear whether cytology specimens obtained with EBUS-TBNA are suitable for the subclassification and genotyping of NSCLC.

OBJECTIVES

To determine whether cytology specimens obtained from EBUS-TBNA in routine practice are suitable for phenotyping and genotyping of NSCLC.

METHODS

Cytological diagnoses from EBUS-TBNA were recorded from 774 patients with known or suspected lung cancer across five centers in the United Kingdom between 2009 and 2011.

MEASUREMENTS AND MAIN RESULTS

The proportion of patients with a final diagnosis by EBUS-TBNA in whom subtype was classified was 77% (95% confidence interval [CI], 73-80). The rate of NSCLC not otherwise specified (NSCLC-NOS) was significantly reduced in patients who underwent immunohistochemistry (adjusted odds ratio, 0.50; 95% CI, 0.28-0.82; P = 0.016). EGFR mutation analysis was possible in 107 (90%) of the 119 patients in whom mutation analysis was requested. The sensitivity, negative predictive value, and diagnostic accuracy of EBUS-TBNA in patients with NSCLC were 88% (95% CI, 86-91), 72% (95% CI, 66-77), and 91% (95% CI, 89-93), respectively.

CONCLUSIONS

This large, multicenter, pragmatic study demonstrates that cytology samples obtained from EBUS-TBNA in routine practice are suitable for subtyping of NSCLC and EGFR mutation analysis and that the use of immunohistochemistry reduces the rate of NSCLC-NOS.