Abstract 735: hPG80 (circulating progastrin), a novel blood-based biomarker for detection of poorly differentiated neuroendocrine carcinoma and well differentiated neuroendocrine tumors

Abstract Background: Current blood-based biomarkers for neuroendocrine neoplasms (NENs) lack both sensitivity and specificity. This is especially true for high-grade NENs (small and large cell neuroendocrine carcinomas). Human circulating progastrin (hPG80) is a novel biomarker for NENs and is easily measured in plasma using an ELISA test. This study is the first to explore hPG80 in NENs. Methods: Progastrin concentrations were quantified in plasma from 95 patients with stage IV NEN using DxPG80 technology (ECS Progastrin, Switzerland) and compared with hPG80 concentrations in 50-80-year-old healthy donors (n=252) as well as a subgroup comprised of only the 18-25-year-olds (n=137). Results: The median hPG80 in NENs patients was 5.54 pM as compared to 1.5 pM for patients in the 50-80-year-old control group and 0.29 pM for patients in the 18-25-year-old cohort (p<0.0001, one-tailed Mann-Whitney U-test). A subgroup analysis of NENs revealed a median hPG80 of 3.54 pM in neuroendocrine carcinoma (NEC n=25) vs 5.8 pM in neuroendocrine tumor (NET n=70). Interestingly small cell lung cancer sub cohort (n=13) also showed significant elevation of hPG80 (9.09 pM). All the above-mentioned differences were statistically significant as compared to healthy controls. Conclusions: Plasma hPG80 in NENs suggests hPG80 may be a diagnostic blood biomarker for both low- and high-grade NENs and further study is warranted. A prospective trial is ongoing in small cell lung cancer to evaluate its role in monitoring of disease (NCT03958045) and further prospective studies in low-grade neuroendocrine tumors are underway. Citation Format: Aman Chauhan, Alexandre Prieur, Jill Kolesar, Susanne Arnold, Thierry Cousin, Lea Payen, Younes Mahi, Madison Sanders, B. Mark Evers, Dominique Joubert, Lowell Anthony. hPG80 (circulating progastrin), a novel blood-based biomarker for detection of poorly differentiated neuroendocrine carcinoma and well differentiated neuroendocrine tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 735.