title: Seed migration after transperineal interstitial prostate brachytherapy by using loose seeds: Japanese prostate cancer outcome study of permanent iodine-125 seed implantation (J-POPS) multi-institutional cohort study.
abstract: BACKGROUND
  The incidence and associated factors of loose seed migration were investigated in cohort 1 of the Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation (J-POPS).
  
  
  METHODS
  The study subjects were 2160 patients, consisting of 1641 patients who underwent permanent iodine-125 seed implantation (PI) and 519 patients who underwent PI combined with external beam radiation therapy (PI + EBRT). The presence or absence of seed migration to the chest and abdominal/pelvic region was determined.
  
  
  RESULTS
  Seed migration was observed in 22.7 % of PI group patients and 18.1 % of PI + EBRT group patients (p = 0.0276). Migration to the lungs and abdominal/pelvic region was observed in 14.6 % and 11.1 % of the patients in the PI group, and 11.2 % and 8.5 % of the patients in the PI + EBRT group, respectively. In the PI group, the number of implanted seeds was associated with the seed migration incidence. Neither the PI nor the PI + EBRT group showed any difference in the volume of the prostate receiving 100 % of the prescribed dose (V100 [%]) or the minimal dose received by 90 % of the prostate volume (D90 [Gy]) between the patients with and without seed migration.
  
  
  CONCLUSIONS
  This prospective cohort study investigating the largest number of past cases showed no difference in D90 (Gy) or V100 (%) between seed migration or the absence thereof in both the PI group and PI + EBRT group.
  
  
  BACKGROUND
  ClinicalTrials.gov: NCT00534196.
authors.affiliation: Department of Urology, Gifu University Graduate School of Medicine, 1-1Yanagito, Gifu-shi, Gifu, 501-1194, Japan. mnakano@gifu-u.ac.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nakano
authors.affiliation: Department of Radiation Oncology, National Hospital Organization, Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan. ayorozu@aol.com.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Yorozu
authors.affiliation: Department of Urology, National Hospital Organization Tokyo Medical Center, 2-5-1 Higashigaoka, Meguro-ku, Tokyo, 152-8902, Japan. saitoshr@netjoy.ne.jp.
authors.forename: Shiro
authors.initials: S
authors.lastname: Saito
authors.affiliation: Department of Radiation Oncology, Tokai University, Hachioji Hospital, 1838 Ishikawa-machi, Hachioji-shi, Tokyo, 192-0032, Japan. aksugawara@yahoo.co.jp.
authors.forename: Akitomo
authors.initials: A
authors.lastname: Sugawara
authors.affiliation: Translational Research Informatics center, 1-5-4 Minatojima-minamimachi Chuo-ku, Kobe, Hyogo, 650-0047, Japan. s-maruo@tri-kobe.org.
authors.forename: Shinichiroh
authors.initials: S
authors.lastname: Maruo
authors.affiliation: Translational Research Informatics center, 1-5-4 Minatojima-minamimachi Chuo-ku, Kobe, Hyogo, 650-0047, Japan. shinkx@tri-kobe.org.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kojima
authors.affiliation: Translational Research Informatics center, 1-5-4 Minatojima-minamimachi Chuo-ku, Kobe, Hyogo, 650-0047, Japan. tkikuchi@tri-kobe.org.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kikuchi
authors.affiliation: Translational Research Informatics center, 1-5-4 Minatojima-minamimachi Chuo-ku, Kobe, Hyogo, 650-0047, Japan. mfukushi@tri-kobe.org.
authors.forename: Masanori
authors.initials: M
authors.lastname: Fukushima
authors.affiliation: Department of Radiology, Kyoundo Hospital, 1-8 Kandasurugadai, Chiyoda-ku, Tokyo, 101-0062, Japan. takushidokiya@hotmail.com.
authors.forename: Takushi
authors.initials: T
authors.lastname: Dokiya
authors.affiliation: Institute of Preventive Medicine, Kurosawa Hospital, 187 Yanakamachi, Takasaki-shi, Gunma, 370-1203, Japan. takahana@amber.plala.or.jp.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Yamanaka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects*; D015331:Cohort Studies; D005548:Foreign-Body Migration / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D007564:Japan; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted
chemical_list: D007457:Iodine Radioisotopes