Karim J Halazun1,2, Russell E Rosenblatt1,2,3, Neil Mehta4, Quirino Lai5, Kaveh Hajifathalian1,2,3, Andre Gorgen6, Gagan Brar7, Kazunari Sasaki8, Maria B Majella Doyle9, Parissa Tabrizian10, Vatche G Agopian11, Marc Najjar2, Tommy Ivanics6, Benjamin Samstein1,2, Robert S Brown2,3, Jean C Emond2, Francis Yao4, Jan Lerut12, Massimo Rossi5, Gianluca Mennini5, Samuele Iesari12, Armin Finkenstedt13, Benedikt Schaefer13, Jans Mittler14, Maria Hoppe-Lotichius14, Cristiano Quintini8, Federico Aucejo8, William Chapman9, Gonzalo Sapisochin6. 1. Division of Liver Transplantation and Hepatobiliary Surgery, Department of Surgery, Weill Cornell Medicine, New York, New York. 2. Center for Liver Disease and Transplantation, Columbia University Medical Center, New York Presbyterian Hospital, New York. 3. Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medical College, New York, New York. 4. Division of Gastroenterology, Department of Medicine, University of California, San Francisco. 5. Sapienza University, Rome, Italy. 6. Multi-Organ Transplant and HPB Surgical Oncology, Division of General Surgery, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada. 7. Center for Advanced Digestive Care, Division of Hematology and Oncology, New York-Presbyterian Hospital, Weill Cornell Medical College of Cornell University, New York. 8. Department of General Surgery, Digestive Disease and Surgery Institute, Cleveland Clinic, Cleveland, Ohio. 9. Section of Abdominal Organ Transplant, Department of Surgery, Washington University School of Medicine, Washington University, St Louis, Missouri. 10. Recanati/Miller Transplantation Institute, Department of Transplantation, Mount Sinai Medical Center, New York, New York. 11. Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California. 12. Institute for Experimental and Clinical Research (IREC) Université catholique de Louvain (UCL), Brussels, Belgium. 13. Gastroenterology and Hepatology, Department of Internal Medicine I, Innsbruck Medical University, Innsbruck, Austria. 14. Department of Transplantation and Hepatobiliary Surgery, University of Mainz, Mainz, Germany.
Abstract
Importance: Accurate preoperative prediction of hepatocellular carcinoma (HCC) recurrence after liver transplant is the mainstay of selection tools used by transplant-governing bodies to discern candidacy for patients with HCC. Although progress has been made, few tools incorporate objective measures of tumor biological characteristics, resulting in inclusion of patients with high recurrence rates and exclusion of others who could otherwise be cured. Objective: To externally validate the New York/California (NYCA) score, a recently published multi-institutional US HCC selection tool that was the first model incorporating a dynamic α-fetoprotein response (AFP-R) and compare the validated score with currently accepted HCC selection tools, namely, the Milan Criteria (MC), the French-AFP (F-AFP), and Metroticket 2.0 models. Design, Setting, and Participants: A retrospective, multicenter prognostic analysis of prospectively collected databases of 2236 adults undergoing liver transplant for HCC was conducted at 3 US, 1 Canadian, and 4 European centers from January 1, 2001, to December 31, 2013. The AFP-R was measured as the difference between maximum and final pre-liver transplant AFP level. Cox proportional hazards regression and competing risk regression analyses examined recurrence-free and overall survival. Receiver operating characteristic analyses and net reclassification index were used to compare NYCA with MC, F-AFP, and Metroticket 2.0. Data analysis was performed from June 2019 to April 2020. Main Outcomes and Measures: The primary study outcome was 5-year recurrence-free survival; overall survival was the secondary outcome. Results: Of 2236 patients, 1808 (80.9%) were men; mean (SD) age was 58.3 (7.96) years. A total of 545 patients (24.4%) did not meet the MC. The NYCA score proved valid on competing risk regression analysis, accurately predicting recurrence-free and overall survival (5-year cumulative incidence of recurrence risk in NYCA risk categories was 9.5% for low-, 20.5%, for acceptable-, and 40.5% for high-risk categories; P < .001 for all). The NYCA also predicted recurrence-free survival on a center-specific level: 453 of 545 patients (83.1%) who did not meet MC, 213 of 308 (69.2%) who did not meet the French-AFP, 292 of 384 (76.1%) who did not meet Metroticket 2.0 would be recategorized into NYCA low- and acceptable-risk groups (>75% 5-year recurrence-free survival). The Harrell C statistic for the validated NYCA score was 0.66 compared with 0.59 for the MC and 0.57 for the F-AFP models (P < .001). The net reclassification index for NYCA was 8.1 vs MC, 12.9 vs F-AFP, and 10.1 vs Metroticket 2.0. Conclusions and Relevance: This study appears to externally validate the importance of AFP-R in the selection of patients with HCC for liver transplant. The AFP-R represents one of the truly objective measures of biological characteristics available before transplantation. Incorporation of AFP-R into selection criteria allows safe expansion of MC and other models, offering liver transplant to patients with acceptable tumor biological characteristics who would otherwise be denied potential cure.
Importance: Accurate preoperative prediction of hepatocellular carcinoma (HCC) recurrence after liver transplant is the mainstay of selection tools used by transplant-governing bodies to discern candidacy for patients with HCC. Although progress has been made, few tools incorporate objective measures of tumor biological characteristics, resulting in inclusion of patients with high recurrence rates and exclusion of others who could otherwise be cured. Objective: To externally validate the New York/California (NYCA) score, a recently published multi-institutional US HCC selection tool that was the first model incorporating a dynamic α-fetoprotein response (AFP-R) and compare the validated score with currently accepted HCC selection tools, namely, the Milan Criteria (MC), the French-AFP (F-AFP), and Metroticket 2.0 models. Design, Setting, and Participants: A retrospective, multicenter prognostic analysis of prospectively collected databases of 2236 adults undergoing liver transplant for HCC was conducted at 3 US, 1 Canadian, and 4 European centers from January 1, 2001, to December 31, 2013. The AFP-R was measured as the difference between maximum and final pre-liver transplant AFP level. Cox proportional hazards regression and competing risk regression analyses examined recurrence-free and overall survival. Receiver operating characteristic analyses and net reclassification index were used to compare NYCA with MC, F-AFP, and Metroticket 2.0. Data analysis was performed from June 2019 to April 2020. Main Outcomes and Measures: The primary study outcome was 5-year recurrence-free survival; overall survival was the secondary outcome. Results: Of 2236 patients, 1808 (80.9%) were men; mean (SD) age was 58.3 (7.96) years. A total of 545 patients (24.4%) did not meet the MC. The NYCA score proved valid on competing risk regression analysis, accurately predicting recurrence-free and overall survival (5-year cumulative incidence of recurrence risk in NYCA risk categories was 9.5% for low-, 20.5%, for acceptable-, and 40.5% for high-risk categories; P < .001 for all). The NYCA also predicted recurrence-free survival on a center-specific level: 453 of 545 patients (83.1%) who did not meet MC, 213 of 308 (69.2%) who did not meet the French-AFP, 292 of 384 (76.1%) who did not meet Metroticket 2.0 would be recategorized into NYCA low- and acceptable-risk groups (>75% 5-year recurrence-free survival). The Harrell C statistic for the validated NYCA score was 0.66 compared with 0.59 for the MC and 0.57 for the F-AFP models (P < .001). The net reclassification index for NYCA was 8.1 vs MC, 12.9 vs F-AFP, and 10.1 vs Metroticket 2.0. Conclusions and Relevance: This study appears to externally validate the importance of AFP-R in the selection of patients with HCC for liver transplant. The AFP-R represents one of the truly objective measures of biological characteristics available before transplantation. Incorporation of AFP-R into selection criteria allows safe expansion of MC and other models, offering liver transplant to patients with acceptable tumor biological characteristics who would otherwise be denied potential cure.