en Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;"><span style="font-size:10pt"><span style="text-justify:newspaper"><span style="text-kashida-space:50%"><span style="line-height:119%"><span style="font-family:Calibri"><span style="color:black"><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Background:</span></span></span></span></span></span> <span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">To investigate the host anti-tumor immune response induced by the combination of endoscopic mucosal resection (EMR) and photodynamic therapy (PDT) in patients with early gastrointestinal cancer (EGIC), and its impact on recurrence and immune modulation. </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Materials and Methods: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">A total of 120 patients diagnosed with EGIC were enrolled and divided into EMR-only (n=60) and EMR+PDT (n=60) groups. Peripheral blood samples were taken before treatment, and on days 7 and 30 post-treatment. Immune markers (CD4+, CD8+ T cells, NK cells) were measured by flow cytometry. Serum cytokines (IL-2, IL-6, IFN-</span></span></span><span lang="el" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:el">&gamma;, </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">TNF-</span></span></span><span lang="el" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:el">&alpha;, </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">IL-10) were assessed using ELISA. Recurrence was tracked over 6 months using endoscopic follow-up. </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Results: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">At day 30, the EMR+PDT group showed significantly elevated CD8+ T cell counts (P<0.01), IFN-</span></span></span><span lang="el" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:el">&gamma; </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">levels (P<0.01), and NK cell activity (P<0.05) compared to EMR-only. There was a marked decrease in Treg cells and IL-10 in the EMR+PDT group (P<0.05). Recurrence rate was 5% in the PDT group versus 18% in EMR-only (P=0.01). </span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Conclusion: </span></span></span></span></span></span><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="language:en-US">PDT combined with EMR enhances host immune responses against tumor cells via immunogenic cell death, improving clinical outcomes in early gastrointestinal cancers.</span></span></span></span></span></span></span></span></span></div> Photodynamic therapy, endoscopic mucosal resection, T cell response, gastrointestinal cancer, host immune modulation. 967 972 http://ijrr.com/browse.php?a_code=A-10-1-1422&slc_lang=en&sid=1 B. Xia 7900319475328460032523 7900319475328460032523 No Department of Gastroenterology, Fuzong Clinical Medical College of Fujian Medical University, 900TH Hospital of PLA Joint Logistics Support Force, Fuzhou City, Fujian Province, China M. Qiu 15980276855@163.com 7900319475328460032524 7900319475328460032524 Yes Department of Gastroenterology, Fuzong Clinical Medical College of Fujian Medical University, 900TH Hospital of PLA Joint Logistics Support Force, Fuzhou City, Fujian Province, China