Targeted Assessment of the EGFR Status as Reflex Testing in Treatment-Naive Non-Squamous Cell Lung Carcinoma Patients: A Single Laboratory Experience (LPCE, Nice, France).

Sandra Lassalle,Marius Ilie,Paul Hofman,Jean-Marc Félix,Elodie Long,Virginie Lespinet,Jacques Boutros,Katia Zahaf,Christelle Bonnetaud,Simon Heeke,Elisabeth Lantéri,Charles Marquette,Olivier Bordone,Salomé Lalvée,Michel Poudenx,Virginie Tanga,Véronique Hofman,Jonathan Benzaquen

doi:10.3390/cancers12040955

Abstract

Background: Assessment of actionable EGFR mutations is mandatory for treatment-naïve advanced or metastatic non-squamous lung carcinoma (NSLC), but the results need to be obtained in less than 10 working days. For rapid EGFR testing, an EGFR-specific polymerase chain reaction (PCR) assay is an alternative and simple approach compared to next generation sequencing (NGS). Here, we describe how a rapid EGFR-specific PCR assay can be implemented in a single laboratory center (LPCE, Nice, France) as reflex testing in treatment-naïve NSLC. Methods: A total of 901 biopsies from NSLC with more than 10% of tumor cells were prospectively and consecutively evaluated for EGFR mutation status between November 2017 and December 2019 using the Idylla system (Biocartis NV, Mechelen, Belgium). NGS was performed for nonsmokers with NSLC wild type for EGFR, ALK, ROS1, and BRAF and with less than 50% PD-L1 positive cells using the Hotspot panel (Thermo Fisher Scientific, Waltham, MA, USA). Results: Results were obtained from 889/901 (97%) biopsies with detection of EGFR mutations in 114/889 (13%) cases using the Idylla system. Among the 562 EGFR wild type tumors identified with Idylla, NGS detected one actionable and one nonactionable EGFR mutation. Conclusions: Rapid and targeted assessment of EGFR mutations in treatment-naïve NSLC can be implemented in routine clinical practice. However, it is mandatory to integrate this approach into a molecular algorithm that allows evaluation of potentially actionable genomic alterations other than EGFR mutations.

Highlights

Around 15–40% of patients with non-squamous lung carcinoma (NSLC) harbor specific mutations in the EGFR gene
We evaluated if the assessment of the EGFR status in NSLC biopsies using an EGFR-specific polymerase chain reaction (PCR) assay still has a place in the daily practice of an academic hospital center, and how this single gene testing approach could be integrated into lung cancer patient care
Atotal of 901/1368 (66%) biopsies had more than a 10% tumor cell content, allowing for the assessment of EGFR mutations using the Idylla assay

Summary

Introduction

Around 15–40% of patients with non-squamous lung carcinoma (NSLC) harbor specific mutations in the EGFR gene. Cancers 2020, 12, 955 that patients with EGFR-mutated NSLC and a history of smoking show response to EGFR tyrosine kinase inhibitor (TKI) treatment, but their outcomes are usually not as good as never-smoking patients [4]. Both never-smokers and smokers have improvement in progression-free survival (PFS) with TKI therapy compared to chemotherapy. Assessment of actionable EGFR mutations is mandatory for treatment-naïve advanced or metastatic non-squamous lung carcinoma (NSLC), but the results need to be obtained in less than 10 working days. Among the 562 EGFR wild type tumors identified with Idylla, NGS detected one actionable and one nonactionable EGFR mutation. It is mandatory to integrate this approach into a molecular algorithm that allows evaluation of potentially actionable genomic alterations other than EGFR mutations

Methods

Discussion

Conclusion