PMID- 33073050 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20201020 IS - 2415-1289 (Electronic) IS - 2415-1289 (Linking) VI - 5 DP - 2020 TI - Gastrointestinal cancers: current biomarkers in esophageal and gastric adenocarcinoma. PG - 55 LID - 10.21037/tgh.2020.01.08 [doi] LID - 55 AB - Esophageal and gastric adenocarcinomas are frequently diagnosed at an advanced stage and have a dismal prognosis. Even in patients with potentially curative cancer, nearly 50% will develop recurrent disease despite aggressive treatments. A number of biomarkers currently guide treatment decisions for patients with esophageal and gastric adenocarcinoma and include human epidermal growth factor receptor 2 (HER2) amplification, mismatch repair deficiency/microsatellite instability (dMMR/MSI-H) and program death-ligand 1 (PD-L1) expression. This review will focus on the function, testing and FDA-approved targeted therapies for HER2, dMMR/MSI-H and PD-L1. In addition, a number of novel targets in esophageal and gastric cancer are being studied in clinical trials. Neurotrophic-tropomyosin receptor kinase (NTRK), claudin-18 (CLDN18)/Rho GTPase activating protein 26 (ARHGAP26) gene fusion, fibroblast growth factor receptor (FGFR), lymphocyte-activation gene 3 (LAG3) and T cell immunoglobulin and mucin-domain containing-3 (TIM3) will be briefly reviewed. Despite several biomarkers used in the selection of treatment therapies, treatment outcomes remain poor. Future research efforts will focus on the identification of new biomarkers, moving existing biomarkers into earlier lines of therapy, and evaluating new combinations of existing biomarkers and therapies. CI - 2020 Translational Gastroenterology and Hepatology. All rights reserved. FAU - Dhakras, Purabi AU - Dhakras P AD - Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, USA. FAU - Uboha, Nataliya AU - Uboha N AD - Division of Hematology, Medical Oncology and Palliative Care, Department of Medicine, University of Wisconsin, Madison, WI, USA. AD - UW Carbone Cancer Center, Madison, WI, USA. AD - William S. Middleton Memorial Veterans Hospital, Madison, WI, USA. FAU - Horner, Vanessa AU - Horner V AD - Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, USA. AD - Wisconsin State Lab of Hygiene, Madison, WI, USA. FAU - Reinig, Erica AU - Reinig E AD - Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, USA. FAU - Matkowskyj, Kristina A AU - Matkowskyj KA AD - Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, USA. AD - UW Carbone Cancer Center, Madison, WI, USA. AD - William S. Middleton Memorial Veterans Hospital, Madison, WI, USA. LA - eng PT - Journal Article PT - Review DEP - 20201005 PL - China TA - Transl Gastroenterol Hepatol JT - Translational gastroenterology and hepatology JID - 101683450 PMC - PMC7530320 OTO - NOTNLM OT - Human epidermal growth factor receptor 2 (HER2) OT - microsatellite instability (MSI) OT - program death-ligand 1 (PD-L1) COIS- Conflicts of Interest: The authors have no conflicts of interest to declare. EDAT- 2020/10/20 06:00 MHDA- 2020/10/20 06:01 PMCR- 2020/10/05 CRDT- 2020/10/19 06:00 PHST- 2019/12/05 00:00 [received] PHST- 2020/01/15 00:00 [accepted] PHST- 2020/10/19 06:00 [entrez] PHST- 2020/10/20 06:00 [pubmed] PHST- 2020/10/20 06:01 [medline] PHST- 2020/10/05 00:00 [pmc-release] AID - tgh-05-2020.01.08 [pii] AID - 10.21037/tgh.2020.01.08 [doi] PST - epublish SO - Transl Gastroenterol Hepatol. 2020 Oct 5;5:55. doi: 10.21037/tgh.2020.01.08. eCollection 2020.