Impact of histological grade of hepatocellular carcinoma on the outcome ofliver transplantation

Hypothesis: Histological grade of hepatocellular carcinoma (HCC) is an impo rtant prognostic factor affecting patient survival after orthotopic liver t ransplantation (OLT). Design: Retrospective analysis. Setting: University-based teaching hospital. Patients: Of 952 OLTs performed between June 1991 and January 1999, 56 OLT recipients had histologically proven HCC in the explant liver. Of those, 53 patients with complete clinicopathologic data were analyzed. A single path ologist blinded to the outcome of each patient reviewed all histological sp ecimens. Results: Median follow-up was 709 days. Overall survival for patients with tumors sized 5 cm or less at 1, 3, and 5 years was 87%, 78%, and 71%, respe ctively (Kaplan-Meier). Univariate analysis revealed the size, number, and distribution of tumors; the presence of microscopic vascular invasion and l ymph node metastasis; histological differentiation; and pTNM stage to be st atistically significant factors affecting survival. Multivariate analysis r evealed histological differentiation and pTNM stage to be the independent a nd statistically significant factors affecting survival (P = .002 and .03, respectively). When pTNM stage was excluded from multivariate analysis, his tological differentiation and size remained the significant independent fac tors (P = .02 and .03, respectively). Three-year survival for patients with small (less than or equal to5 cm) tumor with well- to moderately different iated and poorly differentiated HCC was 82% and 67%, respectively. Three-ye ar survival for patients with large (>5 cm) tumor with well- to moderately differentiated and poorly differentiated HCC was 62.5% and 0%, respectively . Conclusions: In our retrospective experience, histological differentiation had a statistically significant effect on the prognosis of HCC after OLT. H owever, before altering the current OLT selection criteria for patients wit h HCC, prospective studies are required to confirm the impact of histologic al grade on clinical outcome.