Endoscopic ultrasonography-guided interstitial implantation of iodine-125 seeds combined with chemotherapy in the treatment of unresectable pancreatic carcinoma: a prospective pilot study

Background and study aims: Intraoperative and transdermal ultrasonography-mediated brachy-therapies have been proved to be effective in postponing the development of abdominal carcinomas. The main purpose of this study was to evaluate the clinical efficacy and safety of endoscopic ultrasonography (EUS)-guided interstitial implantation of radioactive iodine 125 seeds in advanced pancreatic cancer. Patients and methods: In total, 22 patients with advanced pancreatic cancer and positive fine-needle aspiration results underwent EUS-guided interstitial implantation of iodine seeds. All enrolled patients received routine gemcitabine-based 5-fluorouracil chemotherapy I week after brachytherapy. Results: All 22 patients were successfully implanted with I-125 seeds via EUS, with a median of 10 seeds and a maximum of 30 seeds per procedure. The median follow-up time of patients was 9.3 months, and the estimated median survival time was 9.0 months (95% confidence interval 6.7-11.3 months). Partial remission was achieved in three cases (13.6%) during the 4-week period, and disease in 10 patients (45.5%) remained stable. Cancer finally progressed in 20 patients, all of whom died during 2 years of follow-up. Visual analog scale pain score dropped from 5.07+/-2.63 to 1.73+/-1.91 (P < 0.01) 1 week after brachytherapy but increased again to 3.53+/-1.51 1 month later (P < 0.05 vs. baseline). There were no obvious complications following therapy. Conclusions: EUS-guided interstitial implantation of I-125 seeds may represent a safe alternative treatment option for locally advanced pancreatic cancer. Our preliminary data suggest improvement in pain, but no long-term survival benefit.