Li, ZhihaoZhihaoLiChen, Itsuko Chih-YiItsuko Chih-YiChenCentonze, LeonardoLeonardoCentonzeMagyar, Christian T. J.Christian T. J.MagyarChoi, Woo JinWoo JinChoiIvanics, TommyTommyIvanicsO'Kane, Grainne MGrainne MO'KaneVogel, ArndtArndtVogelErdman, LaurenLaurenErdmanDe Carlis, LucianoLucianoDe CarlisLerut, JanJanLerutLai, QuirinoQuirinoLaiAgopian, Vatche GVatche GAgopianMehta, NeilNeilMehtaChen, Chao-LongChao-LongChenSapisochin, GonzaloGonzaloSapisochin2025-07-102025-07-102025-07-09https://boris-portal.unibe.ch/handle/20.500.12422/213136Background Organ shortages require prioritizing hepatocellular carcinoma (HCC) patients with the highest survival benefit for allografts. While traditional models like AFP, MORAL, and HALT-HCC are commonly used for recurrence risk prediction, the TRIUMPH model, which uses machine learning, has shown superior performance. This study aims to externally validate the model.Methods The cohort included 2844 HCC patients who underwent liver transplantation at six international centers from 2000-2022. The TRIUMPH model utilized a regularized Cox proportional hazards approach with a penalty term for coefficient adjustment. Discrimination was assessed using the c-index, and clinical utility was evaluated via decision curve analysis.Results The most common liver diseases are hepatitis C (49%) and hepatitis B (27%). At listing, 84% meets the Milan criteria, and 91% are within criteria at transplant. Median model for end-stage liver disease score is 10 (IQR:8-14), alpha-fetoprotein level 8 ng/mL (IQR:4-25), and tumor size 2 cm (IQR:1.1-3.0). Living donor grafts are used in 24% of cases. Recurrence rate is 9.1% with a median time to recurrence of 17.5 months. Recurrence-free survival rates at 1/3/5 years are 95.7%/89.5%/87.7%, respectively. The TRIUMPH model achieves the highest c-index (0.71), outperforming MORAL (0.61, p = 0.049) and AFP (0.61, p = 0.04), though not significantly better than HALT-HCC (0.67, p = 0.28). TRIUMPH shows superior clinical utility up to a threshold of 0.6.Conclusions The TRIUMPH model demonstrates good accuracy and clinical utility in predicting post-transplant HCC recurrence. Its integration into organ allocation could improve transplantation outcomes.Liver transplants are a limited resource, so doctors must prioritize patients with liver cancer (HCC) who are most likely to benefit. Some traditional tools exist to help predict cancer recurrence, but a new tool called TRIUMPH, which uses machine learning, may work better. This study looked at 2844 HCC patients who received liver transplants at six international centers. Most had hepatitis-related liver disease, and 9% experienced cancer recurrence after transplant. The TRIUMPH model more accurately predicted which patients would stay cancer-free, outperforming most traditional tools. It also proved more helpful in guiding treatment decisions. These findings suggest TRIUMPH could help doctors make better use of available livers by selecting patients with the best long-term outcomes. This could lead to improved survival and more efficient organ allocation worldwide.en600 - Technology::610 - Medicine & healtharticle10.48620/893714062906110.1038/s43856-025-00994-5