Circulating Transcript Analysis (NETest) in GEP-NETs Treated With Somatostatin Analogs Defines Therapy

Context: Early and precise delineation of therapeutic responses are key issues in neuroendocrine neoplasm/tumor management. Imaging is currently used but exhibits limitations in sensitivity and specificity. The utility of biomarkers is unclear. Objective, Setting, and Design: This prospective cohort study (11 mo) sought to determine whether measurements of circulating neuroendocrine tumor transcripts (NETest) predict responses to somatostatin analogs (SSAs). Patients: The test set consisted of 35 SSA-treated gastroenteropancreatic-NETs (RECISTevaluated). The prospective set consisted of 28 SSA-treated Grade 1–Grade 2 GEP-NETs. Intervention(s): Whole blood for transcript analysis (NETest) and plasma for Chromogranin A (CgA) (baseline), were collected every 4 weeks (prior to SSA injection). Morphologic (multidetector computed tomography/MRI) and functional imaging (99mTc-[HYNIC, Tyr3]-Octreotide) was undertaken at entry and 6-month intervals until progression (RECIST 1.0). Main Outcome Measure(s): Treatment...