Identification and validation of a novel gene signature associated with the recurrence of human hepatocellular carcinoma

Purpose: To improve the clinical management of human hepatocellular carcinoma (HCC) by accurate identification, at diagnosis, of patients at risk of recurrence after primary treatment for HCC. Experimental Design: Two clinicopathologic variables available at diagnosis, vascular invasion and cirrhosis, together with molecular profiling using Affymetrix human HG-U133A and HG-U133B oligonucleotide probe arrays, were used to identify recurrent HCC disease. Results: HCC patients presented clinically at diagnosis with vascular invasion and cirrhosis showed a high rate (78-83%) of developing recurrent disease within 6 to 35 months. In comparison, most of the HCC patients (80-100%) without vascular invasion and cirrhosis remained disease-free. However, the risk of recurrent disease for HCC patients with either vascular invasion or cirrhosis could not be accurately ascertained. Using a pool of 23 HCC patients with either vascular invasion or cirrhosis as training set, a 57-gene signature was derived and could predict recurrent disease at diagnosis, with 84% (sensitivity 86%, specificity 82%) accuracy, for a totally independent test set of 25 HCC patients with either vascular invasion or cirrhosis. On further analysis, the disease-free rate was significantly different between patients that were predicted to recur or not to recur in the test group (P = 0.002). Conclusion: We have presented data to show that by incorporating the status of vascular invasion and cirrhosis available at diagnosis for patients with HCC after partial curative hepatectomy and a novel 57-member gene signature, we could accurately stratify HCC patients with different risks of recurrence.