Background: The Italian Score for Organ Allocation (ISO), a transplant benefit oriented allocation system, was introduced in Italy in 2016. The main objective of this study is to identify risk factors for Drop-Out in hepatocellular (HCC) patients enlisted for LT before (Pre-ISO Era) and after ISO (ISO Era) introduction, while the secondary objective is to evaluate the survival results. Methods: CIFs for liver transplantation and Drop-Out were estimated and compared between eras. Factors associated with Drop-Out were identified through multivariable competing risks regression. Survival results were compared using the log-rank test. Results: Between 2011 and 2020, 410 patients with HCC were listed for LT. We observed 103 vs. 217 LT and 49 vs. 41 Drop-Outs (p< 0.001) during the Pre-ISO and ISO Era, respectively. In the multivariable analysis, ISO ([sHR] 0.43; 95%CI 0.28–0.66,p< 0.001) and Alcoholic Cirrhosis ([sHR] 0.27, 95%CI 0.11–0.70;p= 0.007) were revealed to be protective factors for Drop-Out. One year after listing, the CI for Drop-Out decreased from 13.2% to 6.2% (p= 0.02). Despite no differences observed in post-LT survival, a significant difference in the intention-to-treat survival from enlisting was found (p= 0.0019). Conclusions: Among other factors, ISO results were protective for the Drop-Out risk in HCC patients awaiting LT, with a benefit in ITT-OS survival.
背景：意大利于2016年引入以移植获益为导向的器官分配系统——意大利器官分配评分（ISO）。本研究的主要目的是确定肝细胞癌（HCC）患者在ISO引入前（前ISO时代）和引入后（ISO时代）等待肝移植（LT）过程中退出移植名单的风险因素，次要目标是评估生存结果。方法：估算并比较两个时代中肝移植和退出移植名单的累积发生率函数（CIFs）。通过多变量竞争风险回归分析确定与退出相关的因素。使用对数秩检验比较生存结果。结果：2011年至2020年间，共有410例HCC患者被列入肝移植等待名单。在前ISO时代和ISO时代，分别观察到103例与217例肝移植，以及49例与41例退出（p<0.001）。在多变量分析中，ISO（[sHR] 0.43；95%CI 0.28–0.66，p<0.001）和酒精性肝硬化（[sHR] 0.27，95%CI 0.11–0.70；p=0.007）被证明是退出移植名单的保护因素。列入名单一年后，退出的累积发生率从13.2%降至6.2%（p=0.02）。尽管肝移植后生存率未见差异，但从列入名单开始的意向治疗生存率存在显著差异（p=0.0019）。结论：除其他因素外，ISO系统对等待肝移植的HCC患者的退出风险具有保护作用，并在意向治疗总生存率方面带来获益。
肿瘤(癌症)患者之家