Abstract
<title>Abstract</title> <p>Background Primary liver cancer (PLC) is a leading cause of global cancer mortality, with most patients diagnosed at unresectable stages. While locoregional and systemic therapies provide limited clinical benefit, evidence regarding stereotactic body radiotherapy (SBRT) in heavily pretreated, advanced-stage patients remains limited. This study aimed to evaluate the short-term efficacy and acute safety of CyberKnife (CK)-based SBRT for PLC. Methods This retrospective study included 128 patients with PLC who underwent CK-SBRT between May 2021 and December 2023 at The First Hospital of Hebei Medical University. Follow-up was completed on December 31, 2024, with a median follow-up of 15.0 months (range: 1.0–37.5). Tumor response was assessed using RECIST 1.1 criteria, and adverse events (AEs) were graded according to CTCAE v5.0. Overall survival (OS), progression-free survival (PFS), and local control rate (LCR) were calculated using the Kaplan–Meier method. Prognostic factors were identified by univariate log-rank test and multivariate Cox proportional hazards regression. Results The cohort consisted predominantly of males (85.9%) and patients with advanced-stage disease (88.3%); 73.4% had undergone prior therapies. The 1-, 3-, and 6-month LCRs were 100.0%, 95.6%, and 91.4%, respectively. Median OS was 14 months (95% CI: 10.38–17.61), and median PFS was 7 months (95% CI: 5.07–8.93). Grade ≥ 3 treatment-related AEs occurred in 3.91% of patients and were manageable with supportive care. Multivariate analysis identified tumor number ≥ 3 (HR: 2.332, 95% CI: 1.215–4.475, P = 0.011) and absence of post-SBRT therapy (HR: 2.740, 95% CI: 1.590–4.739, P < 0.001) as independent adverse prognostic factors. Conclusions CK-SBRT provides excellent short-term local control and acceptable acute toxicity for PLC. Given the retrospective nature and relatively short median follow-up of this study, these findings primarily support the role of CyberKnife as a well-tolerated local treatment modality. Larger prospective studies with longer follow-up are needed to confirm its impact on long-term survival. Trial registration: Not applicable (retrospective study).</p>