{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T06:05:27Z","timestamp":1790661927470,"version":"4.1.0"},"reference-count":26,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To compare FLOT and SOX as chemotherapy backbones for neoadjuvant or conversion immunochemotherapy in gastric cancer, with emphasis on pathological efficacy, treatment-related toxicity, treatment feasibility, postoperative safety, and exploratory survival outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This retrospective real-world cohort study included 148 patients with gastric cancer who received preoperative immune checkpoint inhibitor-based therapy, with or without targeted therapy, followed by gastrectomy with D2 lymphadenectomy from 2021 to 2025. Patients were grouped according to chemotherapy backbone: FLOT-based immunochemotherapy (n = 75) or SOX-based immunochemotherapy (n = 73). The primary endpoint was grade 3 or higher treatment-related adverse events. Secondary endpoints included pathological complete response, major pathological response, ypN0 status, R0 resection, adverse event-related treatment modification, postoperative complications, disease-free survival, and overall survival. Exploratory survival analyses included Kaplan\u2013Meier estimation and Firth-penalized Cox proportional hazards regression to account for the limited number of survival events. All subgroup analyses were exploratory and hypothesis-generating.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>FLOT and SOX achieved comparable pathological efficacy. Major pathological response occurred in 42.7% of patients in the FLOT group and 45.2% in the SOX group, while pathological complete response occurred in 18.7% and 27.4%, respectively. ypN0 status, clinical-to-pathological downstaging, and R0 resection rates were also similar. Grade 3 or higher adverse events were numerically more frequent with FLOT than SOX (46.7% vs. 32.9%), as were adverse event-related dose reduction or treatment interruption (36.0% vs. 21.9%). However, postoperative complications were comparable between groups (21.3% vs. 23.3%). Sensitivity analyses excluding targeted therapy showed consistent findings. Exploratory survival analyses were limited by 32 DFS events and 16 deaths and by markedly shorter follow-up in the SOX group. Although the unadjusted hazard ratios numerically favored FLOT for both DFS and OS, multivariable Firth-penalized Cox models substantially attenuated these estimates (DFS adjusted HR, 1.08; 95% CI, 0.50\u20132.34; OS adjusted HR, 1.56; 95% CI, 0.53\u20134.60). Accordingly, no definitive conclusions regarding survival superiority, inferiority, or equivalence could be drawn.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>In this cohort, FLOT and SOX showed broadly comparable pathological efficacy and postoperative complication rates, whereas FLOT was associated with a numerically greater preoperative toxicity and treatment-modification burden. SOX may therefore represent a balanced option in selected patients, but these findings require prospective validation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fimmu.2026.1890256","type":"journal-article","created":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T05:50:33Z","timestamp":1790661033000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["FLOT versus SOX as immunochemotherapy backbones for neoadjuvant or conversion therapy in gastric cancer: efficacy, toxicity, and postoperative safety in a real-world cohort"],"prefix":"10.3389","volume":"17","author":[{"given":"Penghui","family":"Liu","sequence":"first","affiliation":[{"name":"Department of General Surgery, Lanzhou University Second Hospital","place":["Lanzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Na","family":"Li","sequence":"additional","affiliation":[{"name":"Department of General Surgery, Lanzhou 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