Prognosis of hepatocellular carcinoma patients diagnosed under regular surveillance: potential implications for surveillance goal

Aims: The goal of hepatocellular carcinoma (HCC) surveillance is to diagnose cancer at an early stage when treatment is likely to provide the best outcome and thereby, reduce mortality. However, no specific criteria define the ‘early stage’ for tumors diagnosed under HCC surveillance. We aimed to analyze factors that determined the outcome of HCC patients diagnosed under regular surveillance, to find out how early it is necessary to detect tumors during surveillance. Methods: A retrospective cohort of 874 HCC patients with preserved liver function (Child-Pugh A) who were diagnosed under regular HCC surveillance at Samsung Medical Center from 2014 to 2016 and did not receive liver transplantation as an initial treatment were analyzed. The primary outcome was overall survival (OS). Results: Tumor size, presence of vascular invasion, albumin-bilirubin grade, and initial treatment modality were independent factors for OS in multivariable analysis. When categorized according to the tumor size, the risk of mortality increased for tumors of > 3 cm, while tumors of 2–3 cm showed similar mortality risks as tumors of ≤2 cm. When categorized according to the tumor factors, curative-intent treatment (resection or ablation) can be applied to 84.5% with excellent outcomes (5-year OS rate, 93.4%), for tumors of ≤3 cm without vascular invasion. Conclusions: When tumors of ≤3 cm were detected and had no vascular invasion, curative-intent treatment was applied for most patients and showed excellent OS. This finding suggests that to detect tumors of <3 cm without vascular invasion may be considered as the goal of HCC surveillance.