The impact of Karnofsky performance status on prognosis of patients with hepatocellular carcinoma in liver transplantation

Background Functional performance as measured by the Karnofsky Performance Status (KPS) scale has been linked to the outcomes of liver transplant patients; however, the effect of KPS on the outcomes of the hepatocellular carcinoma (HCC) liver transplant population has not been fully elucidated. We aimed to investigate the association between pre-transplant KPS score and long-term outcomes in HCC patients listed for liver transplantation. Methods Adult HCC candidates listed on the Scientific Registry of Transplant Recipients (SRTR) database from January 1, 2011 to December 31, 2017 were grouped into group I (KPS 80-100%, n = 8,379), group II (KPS 50-70%, n = 8,091), and group III (KPS 10-40%, n = 1,256) based on percentage KPS score at listing. Survival was compared and multivariable analysis was performed to identify independent predictors. Results Patients with low KPS score had a higher risk of removal from the waiting list. The 5-year intent-to-treat survival was 57.7% in group I, 53.2% in group II and 46.7% in group III (P < 0.001). The corresponding overall survival was 77.6%, 73.7% and 66.3% in three groups, respectively (P < 0.001). Multivariable analysis demonstrated that KPS was an independent predictor of intent-to-treat survival (P < 0.001, reference group I; HR 1.19 [95%CI 1.07-1.31] for group II, P = 0.001; HR 1.63 [95%CI 1.34-1.99] for group III, P < 0.001) and overall survival(P < 0.001, reference group I; HR 1.16 [95%CI 1.05-1.28] for group II, P = 0.004; HR 1.53 [95%CI 1.26-1.87] for group III, P < 0.001). The cumulative 5-year recurrence rates was higher in group III patients (7.4%), compared with 5.2% in group I and 5.5% in group II (P = 0.037). However, this was not significant in the competing regression analysis. Conclusions Low pre-transplant KPS score is associated with inferior long-term survival in liver transplant HCC patients, but is not significantly associated with post-transplant tumor recurrence.