{ "abstract": "Purpose\n\nPatients with human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer (AGC) and ascites have poor prognosis and are often excluded from clinical trials. Thus, evidence on the effect of trastuzumab deruxtecan (T-DXd) in this population remains limited.Materials and methods\n\nThis subgroup analysis of the EN-DEAVOR (UMIN000049032) study assessed outcomes in patients with T-DXd-treated HER2-positive AGC from Japan, stratified by computed tomography-defined ascites severity: none (ascites not detected), low (confined to the upper or lower abdomen), moderate (neither low nor high), and high (diffusely present throughout the abdomen). The outcomes included overall survival (OS), real-world progression-free survival (rwPFS), ascites response rate, and incidence of grade ≥3 adverse events (AEs).Results\n\nAmong 312 patients, 173, 81, 34, and 20 had no, low, moderate, and high ascites severity, respectively. The median OS was 12.35, 6.77, 6.97, and 5.13 months, respectively, and the median rwPFS was 5.32, 3.68, 3.50, and 2.76 months, respectively, for the no, low, moderate, and high severity groups. The overall ascites response rate to ascites severity was 23.0%. The median OS and rwPFS were 11.83 (95% confidence interval [CI], 7.82-18.96) and 6.64 (95% CI, 4.17-9.56) months, respectively, in responders, and 6.28 (95% CI, 4.90-7.03) and 3.15 (95% CI, 2.17-3.94) months, respectively, in non-responders. Grade ≥3 AE incidence was comparable across subgroups.Conclusions\n\nT-DXd demonstrated efficacy and a manageable safety profile in patients with HER2-positive AGC, including those with severe ascites. The ascites response correlated with improved outcomes.", "abstract_shown": true, "affiliations": [ "Division of Gastroenterology, Chiba Cancer Center, Chiba, Japan.", "Department of Gastroenterology, Saitama Cancer Center, Saitama, Japan.", "Department of Clinical Oncology, Tohoku University Graduate School of Medicine, Sendai, Japan.", "Department of Gastroenterological Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.", "Cancer Center, Gifu University Hospital, Gifu, Japan.", "Department of Genetic Oncology, Osaka International Cancer Institute, Osaka, Japan.", "Division of Digestive Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.", "Department of Biomedical Statistics and Bioinformatics, Kyoto University Graduate School of Medicine, Kyoto, Japan.", "Department of Clinical Oncology, Aichi Cancer Center Hospital, Nagoya, Japan.", "Department of Surgery, Kindai University Faculty of Medicine, Sakai, Japan.", "Department of Gastrointestinal Medical Oncology, NHO Shikoku Cancer Center, Matsuyama, Japan.", "Division of Gastrointestinal Oncology, Shizuoka Cancer Center, Shizuoka, Japan.", "Department of Surgery, Nihonkai General Hospital, Sakata, Japan.", "NHO Nagoya Medical Center, Nagoya, Japan.", "Oncology Medical Science Department I, Daiichi Sankyo Co., Ltd., Tokyo, Japan.", "Data Intelligence Department, Daiichi Sankyo Co., Ltd., Tokyo, Japan.", "Department of Clinical Oncology, Aichi Cancer Center Hospital, Nagoya, Japan. kmuro@aichi-cc.jp." ], "article_type": "research article", "arxiv": null, "author_total": 18, "authors": [ { "affs": [ 0 ], "name": "Keiko Minashi", "orcid": "0000-0003-1513-7117" }, { "affs": [ 1 ], "name": "Rin Inamoto", "orcid": "0009-0009-5696-518X" }, { "affs": [ 2 ], "name": "Hisato Kawakami", "orcid": "0000-0002-3280-4850" }, { "affs": [ 3 ], "name": "Koki Nakanishi", "orcid": "0000-0002-0629-798X" }, { "affs": [ 4 ], "name": "Akitaka Makiyama", "orcid": "0000-0002-4017-668X" }, { "affs": [ 5 ], "name": "Naotoshi Sugimoto", "orcid": "0000-0001-9579-690X" }, { "affs": [ 6 ], "name": "Hirotaka Konishi", "orcid": "0000-0002-4899-8944" }, { "affs": [ 7 ], "name": "Satoshi Morita" }, { "affs": [ 8 ], "name": "Yukiya Narita", "orcid": "0000-0002-8018-0077" }, { "affs": [ 9 ], "name": "Motohiro Imano", "orcid": "0000-0003-2242-4245" }, { "affs": [ 10 ], "name": "Tomohiro Nishina" }, { "affs": [ 11 ], "name": "Takeshi Kawakami", "orcid": "0000-0001-9385-9516" }, { "affs": [ 12 ], "name": "Motohisa Hagiwara" }, { "affs": [ 13 ], "name": "Yasuhiro Kodera", "orcid": "0000-0002-6173-7474" }, { "affs": [ 14 ], "name": "Hiroki Kume" }, { "affs": [ 14 ], "name": "Keita Yamaguchi" }, { "affs": [ 15 ], "name": "Wataru Hashimoto", "orcid": "0009-0007-3682-502X" }, { "affs": [ 16 ], "name": "Kei Muro", "orcid": "0000-0002-5572-743X" } ], "bibtex": "https://research.draconitic.com/paper/64e4g672q3yar.bib", "cited_by": 0, "doi": "10.5230/jgc.2026.26.e42", "fulltext_url": "https://europepmc.org/articles/PMC13655690", "id": "64e4g672q3yar", "issns": [ "2093-582X", "2093-5641" ], "landing_url": "https://europepmc.org/article/MED/42845253", "language": "eng", "licence": "CC-BY-NC", "licence_label": "CC BY-NC", "licence_source": "article", "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/", "metadata_licence": null, "native_subjects": [ [ "openalex", "2740|Gastric Cancer Management and Outcomes" ] ], "openalex": "W7211959751", "pdf_url": "https://europepmc.org/articles/PMC13655690?pdf=render", "pmcid": "PMC13655690", "pmid": "42845253", "published": "2026-10-01", "publisher": null, "ris": "https://research.draconitic.com/paper/64e4g672q3yar.ris", "sources": [ { "first_seen": "2026-10-30T12:18:10Z", "native_id": "MED:42845253", "source": "europepmc", "url": "https://europepmc.org/article/MED/42845253" } ], "subjects": [ { "field": "medicine", "origin": "openalex:2740|Gastric Cancer Management and Outcomes", "subfield": "general" } ], "title": "Clinical Impact of Trastuzumab Deruxtecan in Patients With HER2-Positive Advanced Gastric Cancer and Ascites: Findings From the EN-DEAVOR Study.", "title_text": "Clinical Impact of Trastuzumab Deruxtecan in Patients With HER2-Positive Advanced Gastric Cancer and Ascites: Findings From the EN-DEAVOR Study.", "type": "peer-reviewed", "updated_at": "2026-10-30T12:18:10Z", "url": "https://research.draconitic.com/paper/64e4g672q3yar", "venue": "Journal of gastric cancer", "versions": [] }