Abstract :
[en] Introduction: As there is a lack of deceased liver donors, the liver allocation system of many countries has included a tight selection of the hepatocarcinoma (HCC) patients who may benefit the most from liver transplantation (LT) with the HCC nodules. However, it is clear now that, if size and number matter, the biology of the HCC itself is also of great importance.
Aim: The aim of this study was to evaluate the prognostic value of 18F-fluorodeoxyglucose positron emission tomography coupled with computed tomography (18F-FDG PET/CT) in preLT assessment of patients with chronic liver disease and HCC.
Methods: This is a single-centre retrospective study on 115 HCC patients (mean age: 62 ± 7y) who benefited from 18F-FDG PET/CT before any bridge therapy and underwent LT between January 2010 and December 2021. Follow- up was ended on December 31, 2023. 18F-FDG PET/CT was considered positive when the ratio between the SUVmax of the tumour and the SUVmax of the liver parenchyma (RSUVmax) was > 1.15 (PET pos). RSUVmax was compared
to other preLT prognostic factors, as Milan criteria (in/out), AFP score (≤ or > 2), Up-To- Seven score (in/out, and Metroticket 2.0 score. Overall survival and recurrence-free survivals were evaluated by Kaplan-Meier method. Comparisons of survival between prognostic factors were made using Cox regression.
Results: Among the 115 HCC patients, 32 patients (27.8%) were Milan out, 21 (18.3%) AFP score >2, and 11 (9.6%) Up-to-seven out at time of LT listing. RSUV max was >1.15 in 28 (24.7%) patients. Overall survival was 88.7% and 70.8% at 2 and 5 years, respectively. Recurrence-free survival (RFS) was 91.6% and 80.8% at 2 and 5 years, respectively. In recurrence-free survival analysis in the Milan out group, RSUVmax > 1.15 was the only predictive factor for recurrence in uni- and multivariate analyses. Interestingly, there was no 5-yr RFS difference between Milan in/PET neg, Milan in/PET pos and Milan out/PET neg patients (88%, 83% and 77% respectively), but RFS was significantly worse in Milan out/PET pos patients (20%).
Conclusions: FDG-PET/CT with an RSUVmax cut-off value of 1.15 is a strong prognostic factor for recurrence in Milan out patients. Milan out /PET neg HCC patients might have a good prognosis after LT. Further prospective studies should test whether 18F-FDG PET/CT) should be systematically included in the preLT assessment of Milan outpatients.
