Ultrasound-Guided I Seed Implantation in Treatment of Abdominal Wall Metastases.

Background: The treatment of abdominal wall metastasis presents a challenge, because resection can be followed by poor healing and external radiotherapy is associated with serious adverse events. This study aimed to evaluate the efficacy and safety of interstitial I-125 seed implantation under ultrasound (US) guidance for treating abdominal wall metastasis. Materials and Methods: The cases of 21 patients with 28 abdominal wall metastases who received brachytherapy with I-125 seeds at the department from August 2010 to March 2015 were retrospectively reviewed. I-125 seeds were implanted in the abdominal wall lesions under US guidance and with the help of a treatment planning system. Follow-up was performed using computed tomography at 1 d and at 3, 6, and 12 months after implantation. The lymphocyte count before the surgery was compared with the 3-month postoperative count. The main indicators observed were changes in tumor size, side effects, and complications. Results: All 21 patients were successfully treated with I-125 seed implantation under US guidance. The median follow-up since I-125 seed implantation was 15 months (range 6-23 months). The response rates and local tumor control after 3, 6, and 12 months were 78.6% and 89.3%, 64.3% and 85.7%, and 52.4% and 71.4%, respectively. The mean preoperative lymphocyte count was 0.262 +/- 0.117 x 10(9)/L, which did not differ significantly from the postoperative count, which was 0.259 +/- 0.094 x 10(9)/L (p = 0.122). Procedure-related complications included fever, bleeding, and pain, but all these were Grade 1-2. No severe side effects or complications were noted. Conclusions: Percutaneous interstitial implantation of I-125 seeds under US guidance is safe and feasible for abdominal wall metastases. However, its long-term efficacy requires further investigation.