TACE with or without lenvatinib as adjuvant therapy for HCC with microvascular invasion (MVI) or portal vein thrombus (Cheng’s I/II): A single-center, prospective, non-randomized cohort study.

e16214 Background: Hepatocellular carcinoma (HCC) with microvascular invasion (MVI) or portal vein tumor thrombus (PVTT) is associated with a high risk of tumor recurrence after radical resection. Transarterial chemoembolization (TACE) has been widely used as an adjuvant treatment in China; however, its efficacy in combination with targeted therapies, such as lenvatinib, remains unclear. This study aims to evaluate the efficacy of TACE combined with lenvatinib in preventing recurrence in HCC patients with MVI or PVTT (Cheng's Classification I/II) after radical surgery. (ChiCTR2000040863). Methods: This is a single-center, prospective, non-randomized cohort study. Patients who underwent radical resection of HCC with MVI or PVTT (Cheng's Classification I/II) were enrolled. The patients received lenvatinib (8mg qd for weights < 60kg and 12mg qd for weights≥60kg) in combination with TACE (Len+TACE) or TACE alone. The primary endpoint was recurrence-free survival (RFS), and secondary endpoints included adverse events (AEs), overall survival (OS), and treatment-related mortality. Results: A total of 74 patients were included in the study, 37 patients in each group. The median age was 59.5 years (range from 30 to 75 years). Most patients were males (78.3%) and 57 patients were HBV related (77.0%). There were no significant differences between the two groups in the baseline clinicopathological characteristics including gender, age, HBV background, liver function, tumor characteristic and AFP level. The media RFS was 27.5 months (95% CI: 20.5-NA) in the Len+ TACE group, which was significantly longer than 16.2 months (95% CI: 10.2-NA) in the TACE group (P = 0.04; HR 0.51, 95% CI: 0.27-0.98). The median OS was not reached in both groups. The 1-year and 2-year OS rates for the Len+ TACE group were 96.9% (95% CI: 91.0-100.0) and 85.3% (95% CI: 72.8-99.9), respectively. The 1-year and 2-year OS rates for the TACE group were 94.6% (95% CI: 87.6-100.0) and 73.8% (95% CI: 57.1-95.3), respectively. The most common AEs was hypertension in the Len+TACE group (10.8%). No treatment-related mortality was observed. Conclusions: The combination of lenvatinib and TACE significantly prolonged RFS in HCC patients with MVI or PVTT (Cheng's Classification I/II) after radical resection, with no significant treatment-related AEs. These findings suggest that TACE combined with lenvatinib may be an effective regimen to prevent tumor recurrence in this high-risk population. Clinical trial information: ChiCTR2000040863 .