Conversion therapy for advanced hepatocellular carcinoma with vascular invasion: a comprehensive review

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and has a high mortality rate worldwide. The percentage of HCC patients with vascular invasion at the time of initial HCC diagnosis is 10%-40%. According to most guidelines, HCC with vascular invasion is classified as advanced stage, and resection is only suggested for a minority of such patients. Recently, advances in systemic and locoregional treatments for such patients have resulted in amazing response rates. Therefore, a "conversion therapy" strategy including systemic and locoregional treatments is proposed to select patients from an initially unresectable state to eventually undergo R0 resection. Recently, many studies have proven that conversion therapy followed by subsequent surgery is achievable in well-selected advanced HCC patients and can provide prolonged long-term outcomes. Based on published research, this review has summarized the clinical experience and evidence of conversion treatment in HCC patients with vascular invasion.