Ultrasound-Guided 125I 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 125I 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 125I seeds at the department from August 2010 to March 2015 were retrospectively reviewed. 125I 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 125I seed implantation under US guidance. The median follow-up since 125I 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 × 109/L, which did not differ significantly from the postoperative count, which was 0.259 ± 0.094 × 109/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 125I seeds under US guidance is safe and feasible for abdominal wall metastases. However, its long-term efficacy requires further investigation.