Published online Oct 7, 2014. doi: 10.3748/wjg.v20.i37.13538
Revised: April 18, 2014
Accepted: May 25, 2014
Published online: October 7, 2014
AIM: To define the histopathological features predictive of post-transplant hepatocellular carcinoma (HCC) recurrence after transarterial chemoembolization, applicable for recipient risk stratification.
METHODS: We retrospectively reviewed the specimens of all suspicious nodules (total 275) from 101 consecutive liver transplant recipients which came to our Pathology Unit over a 6-year period. All nodules were sampled and analyzed, and follow-up data were collected. We finally considered 11 histological variables for each patient: total number of nodules, number of viable nodules, size of the major nodule, size of the major viable nodule, occurrence of microscopic vascular invasion, maximum Edmondson's grade, clear cell/sarcomatous changes, and the residual neoplastic volume. Survival data were computed by means of the Kaplan-Meier procedure and analyzed by means of the Cox proportional hazards model. The multivariate linear regression and a k-means cluster analysis were also used in order to compute the standardized histological score.
RESULTS: The total number of nodules, the residual neoplastic volume (the total volume of all evaluated nodules minus the necrotic portion) and the microvascular invasion entered the Cox multivariate hazard model with HCC recurrence as dependent variable. The histological score was therefore computed and a cluster analysis sorted recipients into 3 risk groups, with 3.3%, 18.5% and 53.8% respectively of tumor recurrence rates and 1.6%, 11.1% and 38.5% of tumor-related mortality respectively at the end of follow-up.
CONCLUSION: The histological score allows a reliable stratification of HCC recurrence risk, especially in those recipients found out to be beyond the Milan criteria after orthotopic liver transplantation (OLT).
Core tip: Transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) is used for down-staging before orthotopic liver transplantation (OLT), and as “bridging therapy” to reduce the drop-out rates in the waiting list. A discrepancy exists between the pre-transplant (radiological) and post-transplant (pathological) staging. Few study analyzing the histology of TACE-treated HCC exist. Here we analyzed 11 histological variables in 275 nodules from 101 consecutive OLT recipients and we computed a histological score to stratify recipients into 3 risk groups, with 3.3%, 18.5% and 53.8% respectively of tumor recurrence rates. The histological score allows a better stratification of those recipients beyond the Milan criteria after OLT.