CT-guided implantation of 125I seeds (permanent brachytherapy) for metastatic tumors of the hepatic portal system: Effectiveness and safety in 13 patients

Abstract

PurposeTo retrospectively evaluate the efficacy and safety of CT-guided implantation of 125I seeds (permanent brachytherapy) for metastatic tumors of the hepatic portal system (HPS). Methods and MaterialsBetween January 2012 and January 2015, 13 patients with metastases measuring >3.0 cm in short-axis diameter, which remained in the HPS after conventional chemotherapy and/or transcatheter arterial chemoembolization, and for which an effective therapeutic dose from external beam radiotherapy could not be delivered, received CT-guided 125I brachytherapy. Clinical data were studied retrospectively. In terms of metrological requirements, the minimum dose to 90% of the target volume (D90) was 90–160 Gy for 125I seeds with activity of 2.96 × 107Bq. CT-based evaluation after 2, 4, and 8 weeks, as well as 6 months after implantation enabled review of local control of tumors. ResultsAll symptoms were improved after 125I brachytherapy. The mean value for D90 for implantation of 125I seeds was 136 Gy. Complete response (CR) + partial response (PR) was documented in 61.5%, 69.2%, and 84.6% of patients at 2 weeks, 4 weeks, and 6 months after implantation, respectively. Four of 13 patients had complete response, 7 cases had PR, 1 patient had stable disease, and 1 case had progressive disease. All metastatic foci were controlled by implantation. No serious complications were observed. ConclusionCT-guided 125I brachytherapy is a safe and effective treatment for metastatic tumors of the HPS and can achieve good local control in the short term as long as the radiation dose is sufficient. CT-guided 125I brachytherapy carries few complications, is simple, safe, and a good complement to cancer treatment.