Validation of ROS1 by immunohistochemistry against fluorescent in situ hybridisation on cytology and small biopsy samples in a large teaching hospital

Fast investigative lung cancer pathway and endobronchial ultrasound procedure supported by rapid on-site evaluation

INTRODUCTION

EBUS is a well-established tool for diagnosis and staging of lung cancer in a fast track investigative pathway. However, impact of ROSE in conjunction with EBUS on reduction of time to treatment decision (TTD) for cancer patients is less well known.

AIMS

Our aim was to determine TTD which was defined as the number of working days from EBUS procedure to the discussion at sector lung multidisciplinary team meeting (MDT). Moreover, concordance of ROSE with final diagnosis was evaluated.

METHODS

A retrospective analysis was performed of a prospective data collection in a busy teaching hospital over a four months study period (September to December 2018).

RESULTS

Data from 112 patients was analyzed. There were 61 (54%) males. Mean age was of 70 years (range 43-91). WHO performance status was 0 in 20 (23%), 1 in 57 (51%), 2 in 22 (20%) and 3 in 7 (6%) patients. In total 522 needle passes were performed from 242 sampling sites. Average working days to discuss at MDT after optimal EBUS sampling was 2.087 (range 0-13 working days). ROSE concordance with final cytological diagnosis was 98.4%. The number of needle passes per site for adequate sample and diagnosis in malignant (4.929) vs non-malignant (2.776) involvement was significantly different (p value <0.0001). There was 100% sample adequacy for preliminary diagnosis, immunohistochemistry and predictive molecular testing.

CONCLUSION

ROSE supported fast-investigative pathway by reducing the time to treatment decision (TTD) making at MDT. High concordance with final cytological diagnosis makes it an effective tool to inform meaningful decision making.

Fusion-positive non-small cell lung carcinoma: Biological principles, clinical practice, and diagnostic implications

Based on superior efficacy and tolerability, targeted therapy is currently preferred over chemotherapy and/or immunotherapy for actionable gene fusions that occur in late-stage non-small cell lung carcinoma (NSCLC). Consequently, current clinical practice guidelines mandate testing for ALK, ROS1, NTRK, and RET gene fusions in all patients with newly diagnosed advanced non-squamous NSCLC (NS-NSCLC). Gene fusions can be detected using different approaches, but today RNA next-generation sequencing (NGS) or combined DNA/RNA NGS is the method of choice. The discovery of other gene fusions (involving, eg, NRG1, NUT, FGFR1, FGFR2, MET, BRAF, EGFR, SMARC fusions) and their partners has increased progressively in recent years, leading to the development of new and promising therapies and mandating the development and implementation of comprehensive detection methods. The purpose of this review is to focus on recent data concerning the main gene fusions identified in NSCLC, followed by the discussion of major challenges in this domain.

Technical aspects of the use of cytopathological specimens for diagnosis and predictive testing in malignant epithelial neoplasms of the lung

Lung cancer is a leading cause of cancer mortality worldwide but recent years have seen a rapidly rising proportion of cases of advanced non-small cell carcinoma amenable to increasingly targeted therapy, initially based on the differential response to systemic treatment of tumours of squamous or glandular differentiation. In two-thirds of the cases, where patients present with advanced disease, both primary pathological diagnosis and biomarker testing is based on small biopsies and cytopathological specimens. The framework of this article is an overview of the technical aspect of each stage of the specimen pathway with emphasis on maximising potential for success when using small cytology samples. It brings together the current literature addressing pre-analytical and analytical aspects of specimen acquisition, performing rapid onsite evaluation, and undertaking diagnostic and predictive testing using immunocytochemistry and molecular platforms. The advantages and drawbacks of performing analysis on cell block and non-cell block specimen preparations is discussed.