Impact of histologically confirmed lymph node metastases on patient survival after surgical resection for hepatocellular carcinoma: Report of a Japanese nationwide survey

OBJECTIVE: To clarify the clinical significance of resection of lymph node metastases in patients' hepatocellular carcinoma (HCC). BACKGROUND: Although the presence of lymph node metastasis form HCC has been considered as a systemic disease, prognosis after resection of them remains unknown. METHODS: From the database of a Japanese nationwide survey, 14,872 patients of HCC treated by surgical resection between 2000 and 2005 were enrolled. We modified the current Japanese staging system for HCC, by further dividing stage IVA into stage IVAnon-n1 and stage n1, according to the absence or presence of pathologically proven lymph node metastasis. Thus, the patients classified into 6 disease stages, that is, I (n = 1494), II (n = 8056), III (n = 4243), IVAnon-n1 (n = 701), n1 (n = 112), and IVB (n = 266), and their long-term outcomes were compared. RESULTS: The median follow-up period was 20.6 months. The 3-year overall survival rates of the patients with stage IVAnon-n1, stage n1, and stage IVB were 51.6%, 38.9% and 27.2%, respectively. A multivariate analysis showed that stage IVAnon-n1 would have a similar impact on the survival as stage n1 (hazard ratio: 0.88, 95% confidence interval: 0.59-1.33, P = 0.555), and that stage n1 still represented one class less advanced than stage IVB (hazard ratio: 0.52, 95% confidence interval: 0.34-0.80, P = 0.003). CONCLUSIONS: The prognosis of patients with histologically node-positive HCC was similar to that of patients with locally advanced HCC (stage IVA), which supports the validity of the current Japanese staging system and also partially validates the system proposed by the UICC/AJCC.