近期的研究表明，早期肿瘤缩小（ETS）和反应深度（DpR）反映了不同癌症化疗的结果。本研究使用JCOG1113的数据来评估ETS和DpR与临床结果的关联，该研究证明了对于化疗未经治疗的晚期胆道癌而言，吉西他滨加S-1（GS）相对于吉西他滨加顺铂（GC）的非劣效性。在JCOG1113有354名患者（其中289名有可测量的靶病灶）被分为ETS未达标组和ETS达标组（6周时肿瘤缩小≥20%）以及DpR低组和DpR高组（最大收缩≥40%）直至入组后12周。使用多变量Cox比例风险模型评估ETS和DpR对生存结果的影响。ETS达标组和DpR高组的患者比例在两个治疗组之间相似。ETS达标组的进展自由生存期（PFS）和总生存期（OS）的风险比（HR）分别为0.70（95%置信区间（CI），0.52-0.93）和0.60（95%CI，0.44-0.81）。DpR高组的PFS和OS的HR分别为0.67（95%CI，0.48-0.94）和0.64（95%CI，0.46-0.90）。在亚群体治疗效应模式分析中，GC组ETS达标组多数患者在自参照点后12周未经历疾病进展。作为治疗过程中的标志物，ETS和DpR是有效的工具。ETS在临床上具有实用性，因为它可以在特定时间早期评估治疗结果。© 2023年作者（们）撰稿。由牛津大学出版社发表。

Recent studies suggest that early tumor shrinkage (ETS) and depth of response (DpR) reflect outcomes of chemotherapy in various cancers. This study evaluated the association of ETS and DpR with clinical outcomes using data from JCOG1113, which demonstrated the non-inferiority of gemcitabine plus S-1 (GS) to gemcitabine plus cisplatin (GC) for chemotherapy-naïve advanced biliary tract cancer.In total, 354 (289 with measurable target lesions) patients enrolled in JCOG1113 were divided into ETS-unachieved and ETS-achieved groups (≥20% tumor reduction at week 6) and DpR-low and DpR-high groups (≥40% maximum shrinkage) until 12 weeks after enrollment. The impact of ETS and DpR on survival outcome was evaluated using the multivariable Cox proportional hazard model.The proportions of patients in the ETS-achieved and DpR-high groups were similar between the 2 treatment arms. The hazard ratios (HRs) of progression-free survival (PFS) and overall survival (OS) for the ETS-achieved group were 0.70 (95% confidence interval (CI), 0.52-0.93) and 0.60 (95%CI, 0.44-0.81), respectively. The HRs of PFS and OS for the DpR-high group were 0.67 (95%CI, 0.48-0.94) and 0.64 (95%CI, 0.46-0.90), respectively. In the subpopulation treatment effect pattern plot analysis, most patients in the ETS-achieved group in the GC arm did not experience disease progression after 12 weeks from the landmark.As on-treatment markers, ETS and DpR were effective tools. ETS was clinically useful, because it can be used to evaluate the outcomes of treatment early at a specific time.© The Author(s) 2023. Published by Oxford University Press.