Risk factors for local and distant recurrence of hepatocellular carcinomas after local ablation therapies

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) recurs frequently after local ablation therapies. Recurrence following the therapies may be of two types: local recurrence and distant recurrence. The aim of the current study is to separately elucidate the predisposing factors for each recurrence. METHODS: Among the 2141 consecutive patients with HCC who were admitted to our institute and affiliated hospital between May 1997 and April 2004, 621 patients who had undergone local ablation therapies as the initial treatment were enrolled. Correlations between the clinical backgrounds of the patients and the type of recurrence were analyzed by the Cox proportional hazard model. RESULTS: A multivariate analysis revealed that tumor size (>30 mm; risk ratio 2.80; 95% confidence interval, 1.77-4.45; P < 0.0001), tumor number (> or =2; 1.74, 1.23-2.47, P = 0.002), and the serum alpha-fetoprotein level (>100 ng/mL; (1.62, 1.09-2.41, P = 0.014), which were classified as "tumor factors", were significant predisposing factors for the local recurrence of HCC. In contrast, a low platelet count (<100,000/microL; 1.34, 1.04-1.74, P = 0.03) and the presence of ascites (1.73, 1.16-2.57, P = 0.008), which were classified as "background factors", as well as tumor size (1.83, 1.11-3.01, P = 0.02) and tumor number (2.23, 1.72-3.00, P < 0.0001) were predisposing factors for distant recurrence. CONCLUSION: The predisposing factors for local and distant recurrence of HCC differ and different precautions must be observed to prevent recurrence, depending on the HCC status and background liver functions.