Pathological Complete Response in Advanced Hepatocellular Carcinoma With Portal Vein Tumor Thrombus Following Conversion Therapy With TACE , HAIC , Lenvatinib, and Sintilimab: A Case Report

Hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) is an advanced disease with poor prognosis and limited treatment options. Conversion therapy integrating locoregional and systemic modalities may expand surgical eligibility, but achieving pathological complete response (pCR) remains rare. We report an adult patient with chronic hepatitis B and China Liver Cancer Staging (CNLC) stage IIIb HCC with extensive PVTT. Baseline alpha-fetoprotein (AFP) was 84,246 μg/L and des-γ-carboxy prothrombin (DCP) 3605 mAU/mL. After three cycles of transarterial chemoembolization (TACE) plus hepatic arterial infusion chemotherapy (HAIC) combined with lenvatinib and sintilimab, the tumor markedly regressed, PVTT was downstaged from type III to type II, and tumor markers declined (AFP 115 μg/L, DCP 47.1 mAU/mL). Thirty-two days after cessation of systemic therapy, the patient underwent left hemihepatectomy with portal vein thrombectomy, and histopathology confirmed pCR with complete tumor necrosis and no viable cells in the liver or thrombus. Postoperative follow-up imaging and serial tumor markers demonstrated no recurrence, with AFP normalizing to 5.6 μg/L at 1 month and remaining within normal range during 9 months of follow-up after discontinuation of adjuvant therapy. The patient recovered well and was discharged 2 weeks postoperatively. This case highlights the potential of multimodal conversion therapy combining TACE, HAIC, targeted therapy, and immunotherapy to induce durable pCR in advanced HCC with PVTT, offering a promising strategy to improve outcomes in this highly challenging population.