Effects of iodine-125 seed brachytherapy on patients with heterochronous pulmonary metastasis from hepatocellular carcinoma: A propensity score matching study.

Purpose: To investigate the effects of iodine-125 seed brachytherapy (ISB) on the overall survival (OS) of patients with heterochronous pulmonary metastasis (HPM) secondary to hepatocellular carcinoma (HCC).

Materials and methods: The clinical and imaging data of 123 patients with HPM secondary to HCC treated at a single center from July 2012 to July 2020 were analyzed retrospectively. The patients were divided into ISB and non-ISB groups based on ISB treatment. Propensity score matching yielded 46 pairs of patients. A total of 191 lesions were treated, and the data were evaluated for 6 months after ISB. The OS rates of the two groups were compared using the Kaplan-Meier method. Independent prognostic factors were determined using a Cox proportional hazards regression model.

Results: The percentages of lung lesions in complete remission, partial remission, disease stable, and disease progression stages were 49.2%, 32.8%, 9.6%, and 8.4%, respectively. The disease control rate was 91.6%. The median follow-up time from the initial diagnosis was 47 months and 33 months for the ISB and non-ISB groups, respectively. Patients in the ISB group had a longer OS than those in the non-ISB group (1-year: 95.7% vs. 80.3%; 3-year: 62.9% vs. 45.7%; 5-year: 37% vs. 20.9%; P < 0.05). Multivariate analysis demonstrated that ISB treatment, tumor differentiation, vascular invasion, and Child - Pugh score were independent prognostic factors for survival.

Conclusion: ISB improves local control and OS rates of HPM secondary to HCC; thus, it is an effective and feasible option for patients with HPM secondary to HCC.