Abstract
BACKGROUND: Hepatocellular carcinoma (HCC) has become a growing health concern globally. Microvascular invasion and high tumor burden are key factors limiting the curative effect of selective internal radiation therapy (SIRT). CASE SUMMARY: This case study reports a 49-year-old woman who was diagnosed with China Liver Cancer Staging (CNLC) IIIa HCC and > 15 cm tumor diameter. Initially, due to insufficient future liver remnant and vascular invasion, the tumor was unresectable; however, radical hepatectomy was performed after successful conversion therapy with SIRT using yttrium-90 ((90)Y) resin microspheres followed by hepatic arterial infusion chemotherapy (HAIC) with tyrosine kinase inhibitor (TKI) and anti-programmed death-1 (PD-1) antibody. SIRT using (90)Y resin microspheres was given by the right hepatic artery and chemoembolization was simultaneously performed in the tumor's feeding vessels from the right diaphragmatic artery. HAIC was followed every three weeks with lenvatinib and tislelizumab. At 4 months post-SIRT, the tumor was downstaged to CNLC Ib and the patient successfully underwent hepatectomy. The histopathological examination of the resected specimen showed extensive necrosis. CONCLUSION: This case study provides evidence for an integrated treatment strategy combining SIRT and HAIC with TKI and anti-PD-1 antibodies for patients with large HCC and microvascular invasion. Further confirmatory trials are required in the future.