{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T09:45:13Z","timestamp":1782294313369,"version":"3.54.5"},"reference-count":119,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,2,21]],"date-time":"2020-02-21T00:00:00Z","timestamp":1582243200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPM"],"abstract":"<jats:p>Human epidermal growth factor receptor-2 (HER2)-expression gastro-oesophageal adenocarcinomas (GEA) gained interest as an important target for therapy with trastuzumab. In the current review, we focused the current knowledge on HER2 status in dysplastic and neoplastic gastric conditions, analyzing the methodological procedures to identify HER2 expression\/amplification, as well as the proposed scoring recommendations. One of the most relevant questions to evaluate the useful impact of HER2 status on therapeutic choice in GEAs is represented by the significant heterogeneity of HER2 protein and gene expression that may affect the targeted treatment selection. Future development of biotechnology will continue to evolve in order to offer more powerful detection systems for the assessment of HER2 status. Finally, liquid biopsy as well as mutation\/amplification of several additional genes may furnish an early detection of secondary HER2 resistance mechanisms in GEAs with a better monitoring of the treatment response.<\/jats:p>","DOI":"10.3390\/jpm10010010","type":"journal-article","created":{"date-parts":[[2020,2,21]],"date-time":"2020-02-21T10:49:16Z","timestamp":1582282156000},"page":"10","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["HER2 Heterogeneity in Personalized Therapy of Gastro-Oesophageal Malignancies: An Overview by Different Methodologies"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2878-3572","authenticated-orcid":false,"given":"Antonio","family":"Ieni","sequence":"first","affiliation":[{"name":"Department of Human Pathology in Adult and Developmental Age \u201cGaetano Barresi\u201d, Section of Pathology, University of Messina, 98125 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roberta","family":"Cardia","sequence":"additional","affiliation":[{"name":"Department of Human Pathology in Adult and Developmental Age \u201cGaetano Barresi\u201d, Section of Pathology, University of Messina, 98125 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Pizzimenti","sequence":"additional","affiliation":[{"name":"Department of Human Pathology in Adult and Developmental Age \u201cGaetano Barresi\u201d, Section of Pathology, University of Messina, 98125 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pio","family":"Zeppa","sequence":"additional","affiliation":[{"name":"Department of Medicine and Surgery, University of Salerno, 84131 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1561-4246","authenticated-orcid":false,"given":"Giovanni","family":"Tuccari","sequence":"additional","affiliation":[{"name":"Department of Human Pathology in Adult and Developmental Age \u201cGaetano Barresi\u201d, Section of Pathology, University of Messina, 98125 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"784","DOI":"10.1007\/s00535-019-01577-7","article-title":"Time trends in the incidence of esophageal adenocarcinoma, gastric adenocarcinoma, and superficial esophagogastric junction adenocarcinoma","volume":"54","author":"Matsuno","year":"2019","journal-title":"J. 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