Clinical value of CT-guided radioactive 125I particle implantation combined with 89SrCl2 in relieving pain after failure of external irradiation in patients with prostate cancer bone metastases

Purpose
To evaluate the feasibility and clinical value of computed tomography (CT)-guided radioactive iodine-125 (125I) seeds implantation combined with strontium chloride (89SrCl2) in relieving pain after failure of external irradiation in patients with prostate cancer bone metastases.

Material and methods
Clinical data of 48 patients (aged, 56-85 years) with prostate cancer bone metastases admitted to the Department of Nuclear Medicine of the General Hospital of Northern Theatre Command from January 2019 to December 2023 were retrospectively analyzed. They underwent 125I seeds implantation brachytherapy combined with 89SrCl2 treatment (Group A), and 89SrCl2 treatment alone (Group B).

Results
A total of 722 seeds were implanted in 39 bone metastases of 23 patients in group A; the implantation success rate was 97.44% (38/39), while there were 25 patients in group B. The worst pain, average pain, and present pain scores of group A decreased over time (F-values: 22.47, 5.22, 3.71; p-values: < 0.001, 0.001, 0.007), and the differences in the worst pain, average pain, and present pain scores compared with before treatment were statistically significant at 12 weeks after treatment (t-values: 6.14, 3.36, 2.86; p-values: < 0.001, 0.002, 0.007). The worst pain at 3 days, 4 weeks, 8 weeks, and 12 weeks after treatment was not statistically significant compared with pre-treatment (t = 2.01, p = 0.0501), while statistical significance was observed at the remaining 4 weeks, 8 weeks, and 12 weeks (t = 7.11, 5.31, 6.14; all p < 0.0001). Also, differences in the worst pain, average pain, and present pain scores of group B before and after treatment were documented.

Conclusions
CT-guided radioactive 125I seeds implantation combined with 89SrCl2 for the treatment of pain after failure of external irradiation in patients with prostate cancer bone metastases, is a feasible and effective treatment. The effect is relatively significant for breakthrough pain, which improves the quality of life of patients with bone metastasis-related pain.