PD-1 inhibitor combined with ablation in liver metastasis: A retrospective, multicenter study.

• DOI: 10.1200/jco.2024.42.16_suppl.e14644
• Publication Date: 2024-06-04T19:44:01Z
• Authors: Dengyao Liu; Tao Huang; Zhanguo Sun; Pan Hu; Tao Zhu; Dongcun Huang; Bingchen Xu; Dechao Jiao; Fujun Zhang; Letao Lin
• Keywords: 03 medical and health sciences; 0302 clinical medicine

e14644 Background: This study aimed to retrospectively evaluate the efficacy of ablation combined with programmed cell death protein 1 (PD-1) inhibitor versus PD-1 inhibitor monotherapy in patients with liver metastasis. Methods: We retrospectively enrolled patients with liver metastasis who received PD-1 inhibitor therapy with or without ablation at three medical institutions between January 2017 and September 2022. Progression-free survival (PFS) and 1-year survival rates were compared after propensity score matching. Additionally, intrahepatic and extrahepatic lesion progression and treatment-related adverse events were recorded during follow-up. Finally, prognostic factors for the combined therapy group were analyzed. Results: We included 172 patients and classified them into the combined therapy and PD-1 inhibitor monotherapy (n = 86 each) groups. Patients in the combined therapy group had better median PFS and 1-year survival rates than those in the PD-1 inhibitor monotherapy group. Combined therapy was an independent prognostic factor for PFS in the univariate and multivariate analyses. New lesions constituted the main pattern of progression, with combined therapy showing significantly lower intrahepatic progression, but similar extrahepatic progression rates. Adverse events associated with PD-1 inhibitors were comparable between the two groups. Additionally, 8 (9.3%) patients experienced ablation-related complications. However, neither univariate, nor multivariate analyses revealed the predictive factors for PFS in the combined therapy group. Conclusions: Ablation combined with a PD-1 inhibitor was superior to PD-1 inhibitor monotherapy in improving the survival of patients with liver metastasis.