biostudies-literatureUnknown60(12)Kobayashi S<h4>Background</h4>Systemic chemotherapy with gemcitabine plus S-1 (GEM + S-1), GEM + CDDP plus S-1 (GEM + CDDP + S-1), or gemcitabine plus cisplatin (GEM + CDDP) is standard treatment for advanced biliary tract cancer (aBTC). We aimed to evaluate the efficacy and safety of combination chemotherapy in older patients with aBTC.<h4>Methods</h4>This multicenter prospective observational study (JON2104-B, UMIN000045156) included patients aged ≥ 70 years with aBTC. Inverse-probability weighting propensity-score analyses (IPW) were used to compare overall survival (OS) as the primary endpoint and progression-free survival (PFS) across treatment groups.<h4>Results</h4>This study included 305 patients between August 2021 and January 2023. Of them, 75, 131, 26, 52, and 10 received GEM + CDDP + S-1,Journal of gastroenterology1584-1595https://www.ebi.ac.uk/biostudies/studies/S-EPMC12630146biostudies-literatureCombination chemotherapy for older patients with unresectable biliary tract cancer: a prospective observational study using propensity-score matched analysis (JON2104-B).PMC12630146Shioji KNebiki HOkuyama HAshida RKobayashi SShimizu SArima SIkezawa KTsuji KKobayashi NTsumura HShibuki TUeno MTerashima TSatoh TFuruse JNaganuma ANakachi KOshima KOhno IDoi TTsuchiya KYamamoto KKomatsu YMasaki YKita EUnno MOkamura YAsagi AMaruki YKataoka SNegoro YSakamoto YItoi TNagano HUmemoto KAsama HKojima YMatsumoto KOkano NOzaka MfalseCombination chemotherapy for older patients with unresectable biliary tract cancer: a prospective observational study using propensity-score matched analysis (JON2104-B).<h4>Background</h4>Systemic chemotherapy with gemcitabine plus S-1 (GEM + S-1), GEM + CDDP plus S-1 (GEM + CDDP + S-1), or gemcitabine plus cisplatin (GEM + CDDP) is standard treatment for advanced biliary tract cancer (aBTC). We aimed to evaluate the efficacy and safety of combination chemotherapy in older patients with aBTC.<h4>Methods</h4>This multicenter prospective observational study (JON2104-B, UMIN000045156) included patients aged ≥ 70 years with aBTC. Inverse-probability weighting propensity-score analyses (IPW) were used to compare overall survival (OS) as the primary endpoint and progression-free survival (PFS) across treatment groups.<h4>Results</h4>This study included 305 patients between August 2021 and January 2023. Of them, 75, 131, 26, 52, and 10 received GEM + CDDP + S-1,2025-01-01T00:00:00Z2025 Dec2026-06-05T17:34:10.156Z2026-05-19T03:11:55.267ZS-EPMC126301464091363910.1007/s00535-025-02294-0