{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T22:45:04Z","timestamp":1792104304881,"version":"4.4.0"},"reference-count":18,"publisher":"American Society of Clinical Oncology (ASCO)","issue":"30","content-domain":{"domain":["ascopubs.org"],"crossmark-restriction":true},"short-container-title":["J Clin Oncol"],"published-print":{"date-parts":[[2026,10,20]]},"abstract":"<jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      The ASCOT phase III trial demonstrated that adjuvant S-1, an oral fluoropyrimidine, improved 3-year overall survival (OS) from 67.6% to 77.1% in patients with resected biliary tract cancer (BTC). We report the prespecified final 5-year follow-up analysis. In this multicenter, open-label, randomized trial conducted in Japan, 440 patients with resected BTC were assigned to observation (n = 222) or S-1 (n = 218). S-1 (40 mg\/m\n                      <jats:sup>2<\/jats:sup>\n                      twice daily, 4 weeks on\/2 weeks off, for four cycles) was orally administered. The primary end point was OS in the intention-to-treat population. At a median follow-up of 61.5 months, the 5-year OS was 64% in the S-1 arm and 52% in the observation arm (hazard ratio [HR], 0.72 [95% CI, 0.55 to 0.95]; one-sided\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      = .01). The median OS was 8.2 years with S-1 and 5.9 years with observation. The median relapse-free survival was 3.5 versus 6.1 years (observation\n                      <jats:italic toggle=\"yes\">v<\/jats:italic>\n                      S-1); unstratified and stratified (by primary tumor site and lymph node status) HRs were 0.80 (95% CI, 0.62 to 1.03) and 0.76 (95% CI, 0.59 to 0.98), respectively. Treatment effects were generally consistent across subgroups. These findings confirm a sustained survival benefit with adjuvant S-1 and support its role as a standard treatment for resected BTC.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1200\/jco-26-00017","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T19:59:29Z","timestamp":1790193569000},"page":"2903-2907","update-policy":"https:\/\/doi.org\/10.1200\/crossmark","source":"Crossref","is-referenced-by-count":0,"title":["Five-Year Follow-Up of the Phase III ASCOT Trial of Adjuvant S-1 After Resection for Biliary Tract Cancer"],"prefix":"10.1200","volume":"44","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4050-2086","authenticated-orcid":false,"given":"Masafumi","family":"Ikeda","sequence":"first","affiliation":[{"name":"Department of Hepatobiliary and Pancreatic Oncology, National Cancer Center Hospital East, Kashiwa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kohei","family":"Nakachi","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, Tochigi Cancer Center, Utsunomiya, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masaru","family":"Konishi","sequence":"additional","affiliation":[{"name":"Department of Hepatobiliary and Pancreatic Surgery, National Cancer Center Hospital East, Kashiwa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Riku","family":"Kajikawa","sequence":"additional","affiliation":[{"name":"Japan Clinical Oncology Group Data Center, Clinical Research Support Office, National Cancer Center Hospital, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9735-6630","authenticated-orcid":false,"given":"Hiroshi","family":"Katayama","sequence":"additional","affiliation":[{"name":"Japan Clinical Oncology Group Operations Office, Clinical Research Support Office, National Cancer Center Hospital, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7753-8712","authenticated-orcid":false,"given":"Yusuke","family":"Sano","sequence":"additional","affiliation":[{"name":"Japan Clinical Oncology Group Operations Office, Clinical Research Support Office, National Cancer Center Hospital, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teiichi","family":"Sugiura","sequence":"additional","affiliation":[{"name":"Division of Hepato-Biliary-Pancreatic Surgery, Shizuoka Cancer Center Hospital, Shizuoka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6527-5409","authenticated-orcid":false,"given":"Sohei","family":"Satoi","sequence":"additional","affiliation":[{"name":"Department of Pancreatobiliary Surgery, Kansai Medical University, Hirakata, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6140-7953","authenticated-orcid":false,"given":"Masaaki","family":"Murakawa","sequence":"additional","affiliation":[{"name":"Department of Hepato-Biliary and Pancreatic Surgery, Kanagawa Cancer Center, Yokohama, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akira","family":"Tomokuni","sequence":"additional","affiliation":[{"name":"Department of Gastroenterological Surgery, Osaka International Cancer Institute, Osaka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3516-8765","authenticated-orcid":false,"given":"Satoshi","family":"Nara","sequence":"additional","affiliation":[{"name":"Department of Hepatobiliary and Pancreatic Surgery, National Cancer Center Hospital, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3066-023X","authenticated-orcid":false,"given":"Yu","family":"Takahashi","sequence":"additional","affiliation":[{"name":"Division of Hepatobiliary and Pancreatic Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ken-ichi","family":"Okada","sequence":"additional","affiliation":[{"name":"Department of Gastroenterological Surgery, Tokai University School of Medicine, Isehara, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-5386-5805","authenticated-orcid":false,"given":"Naoki","family":"Hama","sequence":"additional","affiliation":[{"name":"Department of Surgery, NHO Osaka National Hospital, Osaka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keiko","family":"Kamei","sequence":"additional","affiliation":[{"name":"Department of Surgery, Kindai University Faculty of Medicine, Sakai, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ken","family":"Kamata","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, Kindai University Faculty of Medicine, Sakai, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seiji","family":"Natsume","sequence":"additional","affiliation":[{"name":"Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Nagoya, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1729-807X","authenticated-orcid":false,"given":"Takuji","family":"Okusaka","sequence":"additional","affiliation":[{"name":"Department of Hepatobiliary and Pancreatic Oncology, National Cancer Center Hospital, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0663-6117","authenticated-orcid":false,"given":"Junji","family":"Furuse","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Kanagawa Cancer Center, Yokohama, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4480-0029","authenticated-orcid":false,"given":"Makoto","family":"Ueno","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Kanagawa Cancer Center, Yokohama, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"233","reference":[{"key":"e_1_3_11_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.annonc.2022.10.506"},{"key":"e_1_3_11_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.esmoop.2024.103647"},{"key":"e_1_3_11_4_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41572-021-00300-2"},{"key":"e_1_3_11_5_2","unstructured":"Cancer Statistics: 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