Microvascular invasion of hepatocellular carcinoma predicts microvascular invasion of its recurrence: potential implications for salvage liver transplantation?

Background:Microvascular invasion(MVI)can only be assessed on a full surgical specimen.We aimed at evaluating,whether the histology of the primary tumor is predictive of MVI in a hepatocellular carcinoma(HCC)recurrence.Methods:Patients,who underwent liver resection or orthotopic liver transplantation(OLT)for recurrent HCC from January 2001 until June 2018 were eligible for this retrospective analysis.Resected specimens were evaluated for HCC subtype/morphology,vessels encapsulating tumor clusters(VETC)-pattern and MVI.Dichotomous parameters were analyzed using χ^(2)-test andϕ-values,with P values<0.05 being considered significant.Results:Of 230 HCC recurrences,37(16.1%)underwent repeated liver resection(n=22)or OLT(n=15).Of these,67.6%initially exceeded the Milan criteria.MVI correlated Milan criteria(P=0.005),tumor size(P=0.015)and VETC-pattern(P=0.034)in the primary specimen.The recurrences shared many features of the primary HCC such as tumor grade(P=0.002),VETC-pattern(P=0.035),and MVI(P=0.046).In recurrences,however,only the concordance with the Milan criteria correlated with MVI(P=0.018).No patient without MVI in the primary HCC revealed MVI on early recurrence(<2 years)(P=0.035).Conclusions:HCC recurrences share many biological features of the primary tumor.Moreover,early recurrences of MVI-negative HCC never revealed MVI.This finding offers novel concepts,e.g.,patient selection for salvage OLT.