Iodine-125 seed implantation for residual hepatocellular carcinoma or cholangiocellular carcinoma in challenging locations after transcatheter arterial chemoembolization: Initial experience and findings

PURPOSE: To evaluate the clinical efficacy and safety of computed tomography (CT)-guided iodine-125 ((125)I) seed implantation (ISI) for hepatocellular carcinoma (HCC) or cholangiocellular carcinoma (CCC) lesions in challenging locations after transcatheter arterial chemoembolization (TACE). MATERIAL AND METHODS: A retrospective single-center review of 24 patients with HCC or CCC tumors in challenging locations (hepatic dome or close to the heart/diaphragm/hepatic hilum) was conducted. Patients who underwent CT-guided (125)I implantation from May 2014 to January 2019 were recruited. Patients’ demographics and details including technical success, treatment response, patient survival, and complication rate were also evaluated. RESULTS: Treated tumors were located in the hepatic dome (n = 10; 41.7%), subcapsularly (n = 6; 25%), close to the heart (n = 3; 12.5%), and in the liver hilum (n = 5; 20.8%). The mean maximum diameter of tumors in challenging locations was 40.08 ±11.34 mm (range, 25-68 mm). TACE (2 ±1, 1-4 times) was applied before ISI. There were 27 ISI treatments administered (3 patients also received supplemental ISI). The total number of implanted seeds was 1,160, with mean 48 ±16 seed per patient (range, 30-90 seeds). The mean D(90) value for ISI was 125 Gy. Technical success rate was 100%, while a complete response + partial response (CR + PR) was documented in 70.83%, 79.17%, 83.33%, and 79.17% of patients at 3, 6, 12, and 24 months post-ISI, respectively. There were no major complications, although 2 cases experienced (125)I seed transfer to the diaphragm, and 1 case experienced transfer to the heart cavity. CONCLUSIONS: CT-guided ISI for HCC or CCC lesions in challenging locations after TACE is both highly effective and safe.