Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is the third leading cause of cancer related deaths worldwide. Surgical treatments provide a 5 year survival of approximately 60%-70% in carefully selected patients. However tumour recurrence to the liver continues to be a significant issue. Disseminated tumour cells (DTC) have been associated with tumour recurrence and poor prognosis in several epithelial cancers. The biological properties of DTC in HCC and their association with adverse clinical outcomes have not been critically investigated. Methods: DTC were cultured from peripheral blood samples using a protocol that was developed in house. Their molecular and biological properties were studied using immunocytochemistry, molecular assays and a SCID mouse cell transplantation model. Results: Venous blood was collected from 44 patients with HCC, 50 with liver cirrhosis and 20 healthy volunteers. Following 2 weeks of in vitro culture, cell colonies were observed in 6 patients with HCC and 3 patients with cirrhosis. No cell growth was noted in blood cultured from healthy volunteers. Immunocytochemical analysis of cultured cells showed that they express characteristic markers of human hepatocytes. Further they also expressed phenotypic markers compatible with bone marrow or cancer stem cells. Cells cultured from patients with HCC exhibited increased expression of glypican-3 and survivin and decreased expression of LYVE1. They also demonstrated 18- and 43-gene expression signatures associated with poor prognosis in HCC and non-HCC solid tumours. DTC from HCC patients persisted in SCID mice and showed histological features of neoplasia. Survival analysis showed that HCC patients with DTC had reduced median survival compared to those with no DTC (13 months vs. 49 months). Conclusion: DTC are present in a sub-group of patients with aggressive tumour phenotype. An in depth knowledge of these cells is essential to develop novel cell targeted therapies to eradicate microscopic disease and improve survival.