The value of 18 F-FDG PET/CT quantitative indexes in the diagnosis of nondestructive posttransplant lymphoproliferative disorders after pediatric liver transplantation.

BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) is a serious complication after pediatric liver transplantation (pLT), which may lead to death. 18 F-FDG PET/CT is rarely considered in PTLD after pLT and lacks clear diagnostic guidelines, especially in the differential diagnosis of nondestructive PTLD. The aim of this study was to find a quantifiable 18 F-FDG PET/CT index to identify nondestructive PTLD after pLT. METHODS: This retrospective study collected the data of patients who underwent pLT, postoperative lymph node biopsy, and 18 F-FDG PET/CT at Tianjin First Central Hospital from January 2014 to December 2021. Quantitative indexes were established using lymph node morphology and the maximum standardized uptake value (SUVmax). RESULTS: A total of 83 patients met the inclusion criteria and were included in this retrospective study. To distinguish between PTLD-negative cases and nondestructive PTLD cases, according to the receiver operating characteristic curve, (the shortest diameter of the lymph node at the biopsy site [SDL]/the longest diameter of the lymph node at the biopsy site [LDL])*(SUVmax at the biopsy site [SUVmaxBio]/SUVmax of the tonsils [SUVmaxTon]) had the maximum area under the curve (0.923; 95% confidence interval: 0.834-1.000), and the cutoff value was 0.264 according to the maximum value of Youden's index. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 93.6%, 94.7%, 97.8%, 85.7%, and 93.9%, respectively. CONCLUSIONS: (SDL/LDL)*(SUVmaxBio/SUVmaxTon) has good sensitivity, specificity, positive predictive and negative predictive values, and accuracy, and can be used as a good quantitative index for the diagnosis of nondestructive PTLD.

The impact of portal vein reconstruction on portal vein complications after pediatric living-donor liver transplantation with left lobe graft.

BACKGROUND: This study aimed to determine whether the different methods of portal vein reconstruction have an impact on the occurrence of portal vein complications after pediatric living-donor liver transplantation with left lobe graft. METHODS: A total of 567 recipients were eligible for enrollment in this study and were divided into the following 2 groups according to the type of portal vein reconstruction: group 1 underwent anastomosis of the left and right bifurcations of the recipient portal vein to the donor portal vein (type 1), whereas group 2 underwent anastomosis of the bevel formed by the main trunk and right branch of the recipient portal vein to the donor portal vein (type 2). Postoperative portal vein complications and recipient and graft survival rates were compared between the 2 groups before and after propensity score matching. RESULTS: Portal vein complications occurred in 53 (9.3%) patients, including 46 recipients with portal vein stenosis and 7 with portal vein thrombosis. After propensity score matching, the incidence of portal vein stenosis in group 2 was lower than that in group 1 (P = .035). The first diagnosis time of portal vein stenosis in group 2 was later than that in group 1 (P = .033), and the incidence of early portal vein stenosis was lower than that in group 1 (P = .009). There were no statistically significant differences in the incidence of portal vein thrombosis and recipient and graft survival rates between the 2 groups. CONCLUSIONS: Type 2 portal vein reconstruction appears to be a viable technique in pediatric living-donor liver transplantation with left lobe graft that can effectively reduce the incidence of portal vein stenosis.