Proposal of a new prognostic model for hepatocellular carcinoma: an analysis of 403 patients

Background: The prognosis of hepatocellular carcinoma (HCC) is highly dependent on tumour extension and liver function. Recently, two new prognostic scoring systems—the CLIP score, developed by Italian investigators and the BCLC score, developed in Barcelona—have been widely used to assess prognosis in patients presenting with hepatocellular carcinoma. Each system has its own relative limitations. Aims: To create a new prognostic scoring system which is simple, easy to calculate, and suitable for estimating prognosis during radical treatment of early HCC. Methods: A total of 403 consecutive patients with HCC treated by percutaneous ablation at the Department of Gastroenterology, University of Tokyo Hospital, between 1990 and 1997 were used as the training sample to identify prognostic factors for our patients and used to develop the Tokyo score. As a testing sample, 203 independent patients who underwent hepatectomy at the Department of Hepato-Biliary-Pancreatic Surgery were studied. Prognostic factors were analysed by univariate and multivariate Cox proportional hazard regression. Results: The Tokyo score consists of four factors: serum albumin, bilirubin, and size and number of tumours. Five year survival was 78.7%, 62.1%, 40.0%, 27.7%, and 14.3% for Tokyo scores 0, 1, 2, 3, and 4–6, respectively. The discriminatory ability of the Tokyo score was internally validated by bootstrap methods. The Tokyo score, CLIP score, and BCLC staging were compared by Akaike information criterion and Harrell’s c index among training and testing samples. In the testing sample, the predictive ability of the Tokyo score was equal to CLIP and better than BCLC staging. Conclusions: The Tokyo score is a simple system which provides good prediction of prognosis for Japanese patients with HCC requiring radical therapy.