Conversion of initially unresectable hepatocellular carcinoma (HCC) with triple-combination therapy (lenvatinib, anti-PD-1 antibodies, and transarterial therapy): A retrospective analysis

413 Background: Combination therapy with tyrosine kinase inhibitors and anti-PD-1 antibodies can allow selected patients with initially unresectable HCC to convert to surgical resection. We evaluated conversion therapy with a triple combination of lenvatinib (LEN), anti-PD-1 antibodies and transarterial therapy. Methods: We retrospectively searched medical records from 117 consecutive patients with unresectable/advanced HCC who received triple combination therapy between Dec 2018 and Oct 2020 at Tianjin Medical University Cancer Institute & Hospital. Eligible patients were required to have potentially resectable HCC, defined as meeting ≥1 of the following criteria: 1) estimated future liver remnant after radical (R0) resection of < 40% or < 30% in patients with/without cirrhosis, respectively; 2) R0 resection technically difficult to complete; 3) Child-Pugh score ≥7, ECOG performance status ≥1; 4) tumor thrombus in the main portal vein or inferior vena cava; 5) resectable extrahepatic metastases. The primary endpoint was the proportion of patients who underwent a successful resection (conversion rate). Secondary endpoints included objective response rate (ORR), disease control rate (DCR), 6-month disease-free survival (DFS) and safety. Results: Of 37 patients included in the analysis, all received LEN and anti-PD-1 antibodies with transarterial chemoembolization (TACE, n = 22), hepatic arterial infusion chemotherapy (HAIC, n = 9) or both (n = 6). The conversion rate was 40.5% (15) and the ORR and DCR were 67.7% and 86.5% by RECIST v1.1 and 75.7% and 86.5% by mRECIST, respectively. The median conversion time was 4 months (range: 2-15). After a median postoperative follow-up time of 10 months (95% CI, 6.42-13.58), the 6-month DFS rate was 93%. Overall, 89.2% of patients had ≥1 treatment emergent adverse event (TEAE) and 29.7% experienced a Grade 3/4 TEAE, the most common was hypertension (18.9%, n = 7). Conclusions: A triple combination of LEN, anti-PD-1 antibodies and transarterial therapy was well tolerated and effective at converting potentially resectable HCC to resectable disease. These findings warrant confirmation by future prospective studies.