compared with current next-generation sequencing (NGS) work flows, according to a recent study.
Rapid testing maintained concordance with NGS while cutting median turnaround time in half. In addition, an ultrarapid, next-day work flow allowed several highly symptomatic patients with NSCLC to start therapy within 1 week of biopsy, reported Ibiayi Dagogo-Jack, MD, of the Massachusetts General Hospital Waltham Cancer Center and her coauthors.
Molecular testing for patients with NSCLC is necessary to select appropriate therapies; however, “genotyping by NGS requires complex bioinformatics that can create treatment delays,” the investigators wrote in JCO Precision Oncology. “Some patients with NSCLC present with symptomatic disease that requires initiation of treatment before molecular testing results are available. To our knowledge, the impact of molecular testing turnaround time on clinical decision making has not been formally assessed in NSCLC.”
For rapid testing, biopsies were collected from 243 hospitalized patients with newly diagnosed, metastatic NSCLC and were then fixed in formalin. An EGFR-specific polymerase chain reaction assay was then used to identify exon 19 deletions and L858R mutations. The ultrarapid testing phase of the study involved eight highly symptomatic patients with newly diagnosed NSCLC. Biopsy samples in this group were frozen instead of fixed. Both the rapid and ultrarapid testing results were compared with 121 historical biopsies that had been genotyped by NGS.
The rapid testing’s work flow reduced TTI from 37 days to 22 days (P = .01) while maintaining high concordance with NGS (sensitivity, 98%; specificity, 100%). Median turnaround time dropped in half from 14 days to 7 days with rapid testing (P less than .001); ultrarapid testing had a turnaround time of approximately 1 day. The median TTI for the ultrarapid group was 9 days, and several patients were able to begin therapy within 1 week.
The investigators concluded that rapid and ultrarapid testing are a cost-effective, reliable means for decreasing turnaround time and TTI for patients with newly diagnosed, metastatic NSCLC. However, concurrent NGS genotyping should still be performed because NGS results may influence future therapy sequencing. With the ultrarapid work flow, additional sampling is recommended to offset the risk of tissue failure. The investigators noted that “the growing number of actionable targets substantiates the need for diagnostic strategies that expedite molecular analysis.”
The study was funded in part by the National Institutes of Health. Authors reported compensation from Merck, Boehringer Ingelheim, Takeda, and others.
SOURCE: Dagogo-Jack et al. JCO Precis Oncol. 2018 Jul 24. doi: 10.1200/PO.17.00299.