关键词: 前列腺癌, 近距离治疗, 125I粒子, 移位

Abstract: Objective To study the incidence of seed migration after prostate cancer brachytherapy using a loose-seed (125I) implantation technique and to identify the predictors associated with its occurrence. Methods Between December 2003 and June 2010, 270 patients staging T1～T2 underwent permanent prostate brachytherapy at our hospital and were eligible for the study. Pelvic CT and Chest X-rays obtained at follow-up were examined for the number and location of seeds. The patient and treatment variables potentially associated with the occurrence and number of seed migrations were analyzed. Results Incidence rate of seed migration in patient is 8.9％，（24/270）, 27 seeds were found migrated（0.16％，27/17010）, among which 6 seeds migrated to thoracic cavity, 19 seeds migrated into retropubic space and subcutaneous tissue, 2 seeds were discharged through urine or sperm. Conclusions To Decrease Prostate volumn, total number of implanted seeds and extraprostatic placement of seeds can decrease the frequency of seed migration. With history of TURP and hyperplasia of middle lope of prostate are associated with an increased frequency of seed migration. The small proportion of migrated implanted seeds will not effect the dosimetry of target organ of prostate. No severe complications were observed in cases of seeds migration.

Key words: Prostatic neoplasms, Brachytherapy, 125I , Migration