Ultrasound-guided Permanent Iodine-125 Seed Interstitial Implantation For Retroperitoneal Metastatic Carcinoma

Objective: To assess the advantages in the implantation of radioactive 125 I seeds guided by color doppler ultrasound and the feasibility and efficacy of using ultrasound-guided 125 I seed implantation in treating patient with retroperitoneal metastatic carcinoma.Methods: We performed a retrospective review of 20 patients with carcinomas of retroperitoneal metastases that underwent percutaneous radioactive 125 I seed implantation guided by ultrasound at Department of Gastrointestinal Surgery, China-Japan Union Hospital of Jilin University. There were 8 male and 12 female patients with the maximum diameter of the tumor was 2-13.3 cm. All of the 20 patients had prior surgery to resect the original tumor. Among the enrolled patients, 3 cases were primary gastric carcinoma, 4 cases were primary rectal carcinoma, 2 cases were primary renal carcinoma, 2 cases were primary ureter carcinoma, 3 cases were primary cervical carcinoma, 5 cases were primary ovarian carcinoma, and 1 case was primary brian glioma. Different time after the primary resection, all patients had retroperitoneal metastatic carcinomas. All patients received histologic biopsy via fine needle aspiration guided by ultrasonography. Combined with symptoms, signs imaging results and pathological results, the diagnosis of retroperitoneal metastatic carcinoma confirmed. All of these 20 patients suffered from refractory pain in the waist and back.Results: Two months after treatment, CT scans showed that the overall response rate(CR+PR) for all 20 patients was 70%. 3 patient was with complete response(CR), 11 with partial response(PR), 4 with stable disease(SD) and 2 with progressive disease(PD). The rate of pain relief in 20 patients(CR+PR) was 75% in the current study. The follow-up period was 3–30 months. Median survival time was 12 months. After 30 months’ follow-up, there was 1 patient still surviving. 3 patients showed recurrence after seed implantation and died. 6 patients died of metastases. The one-and-two years tumor control rates were 71% and 43%, respectively. Patients in our group presented pain in puncture pathway and low fever(temperature <38.5°C) at 3-10 days after implantation. After symptomatic treatment, these symptoms were relieved. Of all the patients, no major complication was detected after treatment. Fistula, intestinal obstruction, radioactive enteritis, skin and mucous reaction, were not found in our follow-up period. Radioactive seeds migrated to other organs and tissues were not found.Conclusion: With color doppler ultrasound as a guide, there are a lot of advantages in the implantation of radioactive 125 I seeds. Ultrasoundguided permanent 125 I radioactive seed interstitial implantation is a safe, effective, feasible and minimally invasive treatment method of retroperitoneal metastatic carcinoma.