Lymphovascular invasion on explant is associated with presenting tumor characteristics and not direct acting antiviral utilization in hepatitis C candidates undergoing liver transplantation

Aim of the study
Utilization of direct acting antiviral (DAA) therapy in candidates with well-compensated hepatitis C virus (HCV) cirrhosis and hepatocellular carcinoma (HCC) accruing end stage liver disease (MELD) exception points is highly variable among transplant centers based on center location, local organ procurement dynamics, HCV(+) organ availability, and patient preference. The association between DAA utilization prior to transplant and incidence of lymphovascular invasion on explant is unknown.

Material and methods
Retrospective evaluation from 2013-2017 of patients on a liver transplant (LT) waitlist with HCV-related cirrhosis, MELD-Na < 15, and HCC (within T2/Milan criteria). The cohort was divided into the pre-LT DAA treated group and untreated group with clinical/viral demographics collected. Tumor presenting characteristics, locoregional treatments, wait time to LT, dropout rates and explant pathology were compared.

Results
DAAs were used in 44 patients prior to LT (SVR12 of 37/44 [84%]) and 19 left untreated with LT performed in 81% (51/63) of the waitlisted cohort. No significant differences were found between groups with regards to clinical/viral demographics, local-regional therapy (LRT) sessions, or frequency of lymphovascular invasion on explant. The untreated cohort had a higher rate of dropout (6.3% vs. 3.2%) (p = 0.041). On subgroup analysis of 51 subjects undergoing LT, AFP > 250 ng/ml (p = 0.003) and multifocal HCC (> 1 lesion) (p = 0.006) were associated with lymphovascular invasion on explant while DAA therapy was not (p = 0.578).

Conclusions
DAA therapy for waitlist active HCV candidates accruing MELD exception points has no deleterious effects on bridging LRT, nor is it associated with increased frequency of lymphovascular invasion on explant. The latter appears driven by tumor related characteristics (AFP and number of lesions) irrespective of DAA utilization prior to LT.