Clinical efficacy of CT-guided ~(125)I seed implantation therapy for advanced pancreatic cancer / 介入放射学杂志

ABSTRACT

Objective To discuss the clinical efficacy of CT-guided radioactive ~(125)I seed implantation treatment for unresectable pancreatic cancer. Methods Forty patients with inoperable pancreatic cancer were enrolled in this study, including 25 males and 15 females with an median age of 69 years (38-89 years). Treatment planning system (TPS) was used to reconstruct 3-dimensional images of pancreatic tumor and to define the quantity and distribution of ~(125)I seeds. The radioactivity of ~(125)I seeds was 0.5-0.8 mCi/seed. The seeds were implanted into pancreatic tumor under CT guidance at intervals of 1 cm and were kept away from vessels, pancreatic duct and other adjacent important organs. The tumor matched peripheral dose (MPD) was 60-140 Gy. The median amount of implanted ~(125)I seeds was 36 (18-68) in number. CT scan was performed immediately after the procedure to check the quality of the seeds. In addition, 10 patients received concurrent chemotherapy with arterial infusion of gemcitabin and 5-fluororacil (5-Fu) for 3 to 4 therapeutic courses. Results The median diameter of the tumors was 4.9 cm. The follow-up period was 2 to 28 months. After the treatment the refractory pain was significantly relieved (P < 0.05), and Karnofsky score was dramatically increased (P < 0.05). Most patients experienced relief of pain within 2-5 days after implantation. Two months after treatment, on CT scans the tumors showed completed relief (CR) in 3 cases, partial relief (PR) in 20 cases, no change (NC) in 14 cases and progression (PD) in 3 cases. The overall effective rate (CR+PR) was 57.5%. The median survival time for all patients was 10.2 months, while it was 14.7 months, 10.9 months and 7.1 months for patients in stage Ⅱ, stage Ⅲ and stage IV respectively. For patients in stage Ⅱ, stage Ⅲ and stage Ⅳ, the 6-month cumulative survival rate was 100%, 88% and 62% respectively, while the 12-month cumulative survival rate was 70% , 41% and 0% respectively. After the therapy, liver metastasis occurred in 5 cases and chemoembolization was employed. In three patients, immigration of four radioactive seeds to the liver was found. No serious complications, such as upper GI bleeding, pancreatitis, pancreatic fistula formation and radiation colitis, occurred during the follow-up period. Conclusion CT-guided radioactive ~(125)I seed implantation is a safe, effective and minimally-invasive brachytherapy for unresectable pancreatic cancer with reliable short-term efficacy. It has an excellent anti-pain effect. The curative results can be further improved when chemotherapy is employed together. However, its long-term efficacy needs to be observed.