ABSTRACT
PURPOSE: Guidelines advocate molecular profiling in the evaluation of advanced non-small-cell lung cancer (NSCLC) and support the use of plasma circulating tumor DNA (ctDNA)-based profiling for patients with insufficient tissue. Thorough prospective clinical validation studies of next-generation sequencing (NGS)-based ctDNA assays are lacking. We report the multicentered prospective clinical validation of the InVision ctDNA assay in patients with advanced untreated NSCLC. METHODS: A total of 264 patients with untreated advanced NSCLC were prospectively recruited, and their plasma was analyzed using a ctDNA NGS assay for detection of genomic alterations in 36 commonly mutated genes. Tumor tissue was available in 178 patients for molecular profiling for comparison with plasma profiling. The remaining 86 patients were included to compare ctDNA profiles in patients with and without tissue for profiling. RESULTS: Concordance of InVisionFirst with matched tissue profiling was 97.8%, with 82.9% positive predictive value, 98.5% negative predictive value, 70.6% sensitivity, and 99.2% specificity. Considering specific alterations in eight genes that most influence patient management, the positive predictive value was 97.8%, with 97.1% negative predictive value, 73.9% sensitivity, and 99.8% specificity. Across the entire study, 48 patients with actionable alterations were identified by ctDNA testing compared with only 38 by tissue testing. ctDNA NGS reported either an actionable alteration or an alteration generally considered mutually exclusive for such actionable changes in 53% of patients. CONCLUSION: The liquid biopsy NGS assay demonstrated excellent concordance with tissue profiling in this multicenter, prospective, clinical validation study, with sensitivity and specificity equivalent to Food and Drug Administration-approved single-gene ctDNA assays. The use of plasma-based molecular profiling using NGS led to the detection of 26% more actionable alterations compared with standard-of-care tissue testing in this study.
ABSTRACT
OBJECTIVES: Following failure of a platinum-antifolate combination regimen, there is no standard therapy for advanced malignant pleural mesothelioma (MPM). The fibroblast growth factor receptor (FGFR) signaling pathways may be a relevant target in MPM. Dovitinib inhibits multiple tyrosine receptor kinases, predominantly the vascular endothelial growth factor receptors (VEGFR), but also FGFRs, and could be active in MPM. METHODS: This open-label multicentre phase II trial [NCT01769547] enrolled fit, consenting adult patients with advanced MPM who had previously received platinum-antifolate combination chemotherapy and up to one additional line of systemic therapy. Dovitinib was administered orally at 500mg/day for 5days on, 2days off, in 28-day cycles. Response was assessed every 2 cycles using RECIST 1.1 criteria modified for MPM. Correlative studies included FGFR-1 amplification on archival tumour and serum samples for circulating angiogenesis factors. The primary end-point was the proportion of patients progression-free at 3 months (PF3) using a two-stage design. RESULTS: 12 patients (10 males, median age 67) were enrolled. The median number of cycles administered was 2.5 (range 1-8). One unconfirmed partial response was observed. PF3 was 50% (95% confidence interval 28.4% to 88.0%); although the criterion for proceeding to stage II accrual was met, the trial was halted due to a combination of minimal activity with several early progression events and poor tolerability in this patient population. One of 12 tumour specimens had low amplification of FGFR-1. CONCLUSIONS: Dovitinib has minimal activity in previously-treated MPM. The role of the FGFR pathway in MPM remains unclear.
