Prospective Evaluation of the NETest as a Liquid Biopsy for Gastroenteropancreatic and Bronchopulmonary Neuroendocrine Tumors: An ENETS Center of Excellence Experience

Abstract

Background: There is a substantial unmet clinical need for an accurate and effective blood biomarker for neuroendocrine neoplasms (NEN). We therefore evaluated, under real-world conditions in an ENETS Center of Excellence (CoE), the clinical utility of the NETest as a liquid biopsy and compared its utility with chromogranin A (CgA) measurement. Methods: The cohorts were: gastroenteropancreatic NEN (GEP­NEN; n = 253), bronchopulmonary NEN (BPNEN; n = 64), thymic NEN (n = 1), colon cancer (n = 37), non-small-cell lung cancer (NSCLC; n = 63), benign lung disease (n = 59), and controls (n = 86). In the GEPNEN group, 164 (65%) had image-positive disease (IPD, n = 135) or were image-negative but resection-margin/biopsy-positive (n = 29), and were graded as G1 (n = 106), G2 (n = 49), G3 (n = 7), or no data (n = 2). The remainder (n = 71) had no evidence of disease (NED). In the BPNEN group, 43/64 (67%) had IPD. Histology revealed typical carcinoids (TC, n = 14), atypical carcinoids (AC, n = 14), small-cell lung cancer (SCLC, n = 11), and large-cell neuroendocrine carcinoma (LCNEC, n = 4). Disease status (stable or progressive) was evaluated according to RECIST v1.1. Blood sampling involved NETest (n = 563) and NETest/CgA analysis matched samples (n = 178). NETest was performed by PCR (on a scale of 0–100), with a score ≥20 reflecting a disease-positive status and >40 reflecting progressive disease. CgA positivity was determined by ELISA. Samples were deidentified and measurements blinded. The Kruskal-Wallis, Mann-Whitney U, and McNemar tests, and the area under the curve (AUC) of the receiver-operating characteristics (ROC) were used in the statistical analysis. Results: In the GEPNEN group, NETest was significantly higher (34.4 ± 1.8, p < 0.0001) in disease-positive patients than in patients with NED (10.5 ± 1, p < 0.0001), colon cancer patients (18 ± 4, p < 0.0004), and controls (7 ± 0.5, p < 0.0001). Sensitivity for detecting disease compared to controls was 89% and specificity was 94%. NETest levels were increased in G2 vs. G1 (39 ± 3 vs. 32 ± 2, p = 0.02) and correlated with stage (localized: 26 ± 2 vs. regional/distant: 40 ± 3, p = 0.0002) and progression (55 ± 5 vs. 34 ± 2 in stable disease, p = 0.0005). In the BPNEN group, diagnostic sensitivity was 100% and levels were significantly higher in patients with bronchopulmonary carcinoids (BPC; 30 ± 1.3) who had IPD than in controls (7 ± 0.5, p < 0.0001), patients with NED (24.1 ± 1.3, p < 0.005), and NSCLC patients (17 ± 3, p = 0.0001). NETest levels were higher in patients with poorly differentiated BPNEN (LCNEC + SCLC; 59 ± 7) than in those with BPC (30 ± 1.3, p = 0.0005) or progressive disease (57.8 ± 7), compared to those with stable disease (29.4 ± 1, p < 0.0001). The AUC for differentiating disease from controls was 0.87 in the GEPNEN group and 0.99 in BPC patients (p < 0.0001). Matched CgA analysis was performed in 178 patients. In the GEPNEN group (n = 135), NETest was significantly more accurate for detecting disease (99%) than CgA positivity (53%; McNemar...

NETest is superior to chromogranin A in neuroendocrine neoplasia: a prospective ENETS CoE analysis

“…NETest levels, however, were significantly higher in PD than in SD consistent with a multigene biomarker that assessed molecular genomic regulators of disease activity. These observations of the NETest confirm a recent prospective study in an ENETS CoE (54), and are consistent with a number of other studies that demonstrate that the NETest is an accurate marker of disease status (28,31,34).…”

Molecular Genomic Blood Biomarkers for Neuroendocrine Tumors: The Long and Winding Road from Berzelius and Bence Jones to a Neuroendocrine Destination

“…While neither grading nor staging alone are effective as therapy predictors, the need therefore to accurately identify whether a therapy is effective and that disease is progressive is a critical requirement for optimizing management. The paper by Malczewska et al [1] from an ENETs Centre of Excellence supports reports from many different institutions and confirms the clinical utility of a molecular genomic liquid biopsy for NETs. It provides reproducible, accurate, and clinically reliable information for the physician.…”

“…Dr. A. Malczewska and her colleagues at the Neuroendocrine Tumor Center of Excellence at the Medical University of Silesia are to be congratulated on their large study of the clinical utility of the NETest across a broad range of neuroendocrine tumors (NETs) including pancreas, small bowel, and bronchopulmonary tumors [1]. Their very positive assessment fully supports the conclusions of more than 40 papers from diverse authors and institutions throughout Europe and North America.…”

“…Individual utility is optimally evaluated in clinical studies structured to conform to biomarker study criteria such as Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK) or the Standards for Reporting of Diagnostic Accuracy (STARD) [6]. Such studies have been lacking in NETs, given the absence of an effective general-purpose multianalyte biomarker (NETest) such as reported by Malczewska et al [1]. It is important to identify the scientific power of a CB.…”

“…They direct therapy and are included in various guidelines as standard of care, e.g., the American Society of Clinical Oncology (ASCO) and the National Comprehensive Cancer Network (NCCN). The information provided by Malczewska et al [1] demonstrates that this strategy is now applicable to NET disease. More recent sophisticated inves­tigation of NETest “omic cluster analysis” strategies indicates that further mathematical extrapolation may provide additional clinically relevant information to predict tumor behavior [17].…”