606 Background: There is no accurate blood biomarker of neuroendocrine tumor (NET) disease. The inability to effectively assess disease in real-time has hindered management. The advance of genomic medicine and the development of molecular biomarkers has provided a strategy – liquid biopsy – to facilitate management. We reviewed the role of a blood mRNA-based NET biomarker, the NETest, as an in vitro diagnostic (IVD) to assess clinical utility. Methods: A systematic review of the literature using PRISMA guidelines was undertaken. The methodological quality was evaluated using the QUADAS-2 tool. We identified 10 original scientific papers, which met inclusion criteria. These were assessed by qualitative analysis, and thereafter meta-analysis. Data were pooled and median (95% CI) diagnostic odds ratio (DOR), positive likelihood ratio (+LR) and negative likelihood ratio (–LR) calculated. For the meta-analysis, a generic inverse variance method was undertaken using the accuracy and AUC data. Results: The ten studies exhibited moderate to high methodological quality. They evaluated NETest usage both as a diagnostic and as a monitoring tool. Meta-analysis identified the diagnostic accuracy of the NETest to be 94.9-96% with a median DOR of 400, +LR of 164 and–LR of 0.05. The NETest was 85.5-86% accurate in differentiating stable from progressive disease. As a marker of natural history, the accuracy was 90-94%. As an interventional/ response biomarker, the accuracy was 94-97%. The pooled AUC for the NETest was 0.954±0.005, with a z-statistic of 175.06 ( p< 0.001). Conclusions: The NETest is an accurate biomarker suitable for clinical use in NET disease management. The meta-analysis supports the utility of the NETest as an IVD to establish a diagnosis and monitor therapeutic efficacy. The use of a multianalyte genomic test as a biomarker provides information relevant to NET management consistent with observations regarding the utility of liquid biopsy in other oncological disciplines.
A meta-analysis of the accuracy of a neuroendocrine tumor mRNA genomic biomarker (NETest) in blood
