Hyun Ju Kim1, Sangjoon Park1, Kyoung-Jin Kim1, Jinsil Seong2. 1. Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, South Korea. 2. Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, South Korea. Electronic address: jsseong@yuhs.ac.
Abstract
PURPOSE: To investigate the clinical implications of the soluble programmed cell death-ligand 1 (sPD-L1) level in hepatocellular carcinoma (HCC) patients treated with radiotherapy (RT). MATERIALS/ METHODS: HCC patients treated with RT between June 2011 and March 2015 were prospectively recruited and sPD-L1 levels were measured using an enzyme-linked immunosorbent assay. Blood samples were obtained at the RT start, RT end, and 1-month follow-up. The associations of the sPD-L1 level with the clinical features and outcomes were analyzed. RESULTS: Fifty-three patients with HCC were included. Thirty-four patients received conventional fractionated RT with hepatic arterial infusional chemotherapy, while 19 patients received stereotactic body radiotherapy (SBRT). The initial sPD-L1 level was significantly associated with stage, tumor size, portal vein tumor thrombosis, and venous invasion. The overall-survival was significantly poorer in patients with a higher level of initial sPD-L1 (≥1.315 pg/mL). A higher level of sPD-L1 at 1 month (≥12.9 pg/mL) was significantly related to early lung metastasis. The sPD-L1 level was significantly increased after RT and the change pattern of sPD-L1 was different between two RT schemes. CONCLUSIONS: The level of sPD-L1 was associated with tumor aggressiveness and outcomes, suggesting its role as a possible predictive biomarker. The increases in sPD-L1 after RT suggests that combined treatment with RT and immune checkpoint inhibitors may be a promising therapeutic strategy in HCC.
PURPOSE: To investigate the clinical implications of the soluble programmed cell death-ligand 1 (sPD-L1) level in hepatocellular carcinoma (HCC) patients treated with radiotherapy (RT). MATERIALS/ METHODS: HCC patients treated with RT between June 2011 and March 2015 were prospectively recruited and sPD-L1 levels were measured using an enzyme-linked immunosorbent assay. Blood samples were obtained at the RT start, RT end, and 1-month follow-up. The associations of the sPD-L1 level with the clinical features and outcomes were analyzed. RESULTS: Fifty-three patients with HCC were included. Thirty-four patients received conventional fractionated RT with hepatic arterial infusional chemotherapy, while 19 patients received stereotactic body radiotherapy (SBRT). The initial sPD-L1 level was significantly associated with stage, tumor size, portal vein tumor thrombosis, and venous invasion. The overall-survival was significantly poorer in patients with a higher level of initial sPD-L1 (≥1.315 pg/mL). A higher level of sPD-L1 at 1 month (≥12.9 pg/mL) was significantly related to early lung metastasis. The sPD-L1 level was significantly increased after RT and the change pattern of sPD-L1 was different between two RT schemes. CONCLUSIONS: The level of sPD-L1 was associated with tumor aggressiveness and outcomes, suggesting its role as a possible predictive biomarker. The increases in sPD-L1 after RT suggests that combined treatment with RT and immune checkpoint inhibitors may be a promising therapeutic strategy in HCC.