CT-guided ¹²⁵I seeds interstitial implantation for the refractory liver cancers ineffective to commonly used therapies

Objective: To evaluate the safety and clinical efficacy of CT-guided ¹²⁵I seeds interstitial implantation in treating the refractory liver cancers that show poor response to commonly used therapies. Methods: A total of 40 patients with refractory clinically or pathologically-proved liver cancer were enrolled in this study, the diseases included primary liver cancer (n = 27, with coexisting portal vein cancerous thrombus in 2) and metastatic liver cancer (n = 13). CT-guided ¹²⁵I seeds interstitial implantation was performed in all patients. Preoperative plan of seeds implantation protocol was formulated by using the treatment plan system (TPS); the ¹²⁵I seed activity was 0.6-0.8 mCi and the peripheral matching dose (MPD) was 100-140 Gy. The procedure of ¹²⁵I seeds interstitial implantation was performed under local anesthesia in all patients. By using percutaneous trans-hepatic puncturing and single-or multiple-needle technique, the ¹²⁵I seeds were implanted along a line parallel to the long axis of the tumor and/or tumorous thrombus with an interval of 0.5-1.0 cm. The short-term efficacy was evaluated by modified response evaluation criteria in solid tumors (mRECIST), and the median time to tumor progression (mTTP) and the median overall survival time (mOS) were calculated by Kaplan and Meier method. Results: The technical success rate was 100%. The diameter of the tumor was 1.5-12.0 cm (mean 4.0 cm), and a total of 1748 ¹²⁵I seeds were implanted in 40 patients (mean 44 seeds per patient). The short-term effective rate was 37.5% (n = 15), including complete remission in 8 cases and partial remission in 7 cases, the stable disease was seen in 15 cases (37.5%), and the disease control rate was 75%. The mTTP was 7.0 months (95%CI: 4.524-9.476 months), while mOS was 10 months (95%CI: 6.901-13.099 months). The procedure-related adverse reactions included small amount of subcapsular hemorrhage (n = 2.5%), intrahepatic migration of ¹²⁵I seeds (n = 2.5%), pain at liver area (n =1, 2.5%); and no special treatment was needed in these patients. One patient developed high fever with chills 3 hours after the procedure, which was relieved after symptomatic and antipyretic treatment. Conclusion: For the treatment of refractory liver cancers, CT-guided ¹²⁵I seeds permanent interstitial implantation,used as a remedial therapy, is safe and effective. This technique is worth popularizing in clinical practice. (authors)