Effect of Tacrolimus Time in Therapeutic Range on Postoperative Recurrence in Patients Undergoing Liver Transplantation for Liver Cancer.

BACKGROUND AND OBJECTIVE: Liver cancer is the second highest cause of cancer-related deaths worldwide. It is commonly treated with liver transplantation, where tacrolimus is typically used as an antirejection immunosuppressant. The purpose of this study was to evaluate the effect of tacrolimus time in therapeutic range (TTR) on liver cancer recurrence in liver transplant recipients and to compare the performance of TTRs calculated according to the target ranges recommended in published guidelines. METHODS: A total of 84 patients who underwent liver transplantation for liver cancer were retrospectively included. Tacrolimus TTR was calculated using linear interpolation from the date of transplantation until recurrence or the last follow-up according to target ranges recommended in the Chinese guideline and international expert consensus. RESULT: Twenty-four recipients developed liver cancer recurrence after liver transplantation. The CTTR (TTR calculated according to the Chinese guideline) for the recurrence group was significantly lower than that of the nonrecurrence group (26.39% vs. 50.27%, P < 0.001), whereas the ITTR (TTR calculated according to the international consensus) was not significantly different between the two groups (47.81% vs. 56.37%, P = 0.165). Multivariate survival analysis revealed that age, microvascular invasion, hepatocellular carcinoma, CTTR, and mean tacrolimus trough concentration were independent predictors of liver cancer recurrence after liver transplantation. CONCLUSIONS: TTR predicts liver cancer recurrence in liver transplant recipients. The range of tacrolimus concentrations recommended in the Chinese guideline was more beneficial than that recommended in the international consensus for Chinese patients undergoing liver transplantation for liver cancer.

Lower tacrolimus time in therapeutic range is associated with inferior outcomes in adult liver transplant recipients.

Previous studies on solid organ transplantation have reported that a low time in therapeutic range (TTR) of tacrolimus increases the risk of poor outcomes. However, the reproducibility of the findings in liver transplantation has not yet been confirmed. The TTR, coefficient of variation (CV) and standard deviation (SD) were calculated for 207 adult liver transplant patients from the date of transplantation until the first episode of acute rejection (AR), graft loss, acute kidney injury (AKI), biliary complications, infection or the last follow-up. Kaplan-Meier curves, log-rank tests and Cox regression analyses were performed. Sixty-one (29.5%) patients reached the composite endpoint of AR, biliary complications and graft loss. The log-rank test indicated that the low TTR group had an increased risk of the composite endpoint (P < 0.001), AKI (P < 0.001) and infection (P < 0.001). Multivariate Cox regression analyses revealed that a 10% decrease in TTR was associated with an increased hazard for composite endpoint (hazard ratio [HR]: 1.185, P = 0.010), AKI (HR: 1.355, P < 0.001) and infection (HR: 1.357, P < 0.001). Unexpectedly, SD and CV demonstrated no association with the above-mentioned inferior outcomes. Compared with SD and CV, the TTR of tacrolimus was more correlated with inferior outcomes and may be a novel indicator for predicting the prognosis of liver transplantation.