Is 0.6% Reasonable as the Minimum Requirement of the Graft-to-recipient Weight Ratio Regardless of Lobe Selection in Adult Living-donor Liver Transplantation?

Abstract

Original Clinical Science-Liver Background. Several studies reported favorable outcomes of small-for-size grafts with graft-to-recipient weight ratio (GRWR) <0.8% in living-donor liver transplantation (LDLT). However, their indications should be carefully determined because they must have been indicated for low-risk cases over larger grafts with 0.8% ≤ GRWR. Furthermore, evidence for minimum requirements of GRWR remains inconclusive. We investigated the safety of small-for-size grafts against larger grafts by adjusting for confounding risk factors, and minimum requirement of graft volume in adult LDLT. Methods. We enrolled 417 cases of primary adult-to-adult LDLT in our center between 2006 and 2019. The outcomes of small grafts (0.6% ≤ GRWR < 0.8%, n = 113) and large grafts (0.8% ≤ GRWR, n = 289) were mainly compared using a multivariate analysis and Kaplan-Meier estimates. Results. The multivariate analysis showed that small grafts were not a significant risk factor for overall graft survival (GS). In the Kaplan-Meier analysis, small grafts did not significantly affect overall GS regardless of lobe selection (versus large grafts). However, GRWR < 0.6% was associated with poor overall GS. Although there were no significant differences between the 2 groups, unadjusted Kaplan-Meier curves of small grafts were inferior to those of large grafts in subcohorts with ABO incompatibility, and donor age ≥50 years. Conclusions. Similar outcomes were observed for small and large graft use regardless of lobe selection. 0.6% in GRWR was reasonable as the minimum requirement of graft volume in LDLT. However, small grafts should be indicated carefully for high-risk cases.

Living Donor Liver Transplantation With Augmented Venous Outflow and Splenectomy

“…Also, postreperfusion splenectomy was performed based on graft hemodynamics regardless of graft type and size. A similar approach has been reported by others, with splenectomy rates of 80% of RLG (H5678)-LDLT in the Kyushu group and 61% of LDLT with GRWR >0.8% in the Kyoto group 12,40. In contrast, PCS41 and SAL42 have been widely utilized in Western countries 17.…”

HPi: A Novel Parameter to Predict Graft-related Outcome in Adult Living Donor Liver Transplant

“…Authors have shown excellent outcomes even in patients with GRWR <0.8, such as left lobe grafts. 30,[41][42][43] High portal inflow and pressure across liver graft lead to graft injury and poor graft-related survival. [22][23][24][25] Studies show that PVP and GRSVR are better variables to predict the occurrence of EAD, 24,41,44 similar results were seen in our study where high ΔP post and low GRSVR were identified as factors determining EAD occurrence (Table 2).…”

Association between Hepatocellular Carcinoma Recurrence and Graft Size in Living Donor Liver Transplantation: A Systematic Review

“…A total of 45 papers were identified and screened. In 16 studies, the vast majority of authors reported their survival and SFSS-rates after LDLT using a cut-off for GRWR at <0.8% vs. ≥0.8% ( Table 1 ) [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. Most studies report a lower DFS when the liver volume is lower (i.e., GRWR < 0.8) compared to higher volumes.…”