Testing Patterns and Detection of Exon 20 Insertions in the United States.

INTRODUCTION

exon 20 insertions () are a diverse set of mutations in NSCLC that are refractory to tyrosine kinase inhibitors. We describe real-world detection patterns in patients with advanced NSCLC in the United States.

METHODS

Data from 2011 to 2020 were extracted from the Flatiron Health electronic health record-derived deidentified database.

RESULTS

Among 67,281 patients with advanced NSCLC and at least two clinic visits, 66.8% were tested for mutations, of whom 13.9% tested positive. Of these, 4.9% had . The median time from NSCLC diagnosis to the first positive test result was 23 days, including 9 days of laboratory testing time. The were reported in 0.6% to 1.0% of all patients with advanced NSCLC and account for 3.9% to 5.3% of all mutations. During the study period, reverse transcription-polymerase chain reaction testing rates decreased whereas next-generation sequencing rates increased both in overall and among patients with tumors positive for . Tissue was the most common sample type used for and detection (81.1% and 84.9%, respectively), whereas blood sampling for detection increased from 0% (2011) to 37.2% (2020). For 23.7% of patients with , treatment was initiated before receiving the first positive test result, with therapies including immuno-oncology agents as the most common treatment type from 2017 to 2020.

CONCLUSIONS

testing and detection of in patients with NSCLC have increased slightly over time with the increasing use of next-generation sequencing. The current late-stage development of -targeted therapy is driving a need for more efficient testing.