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

Masahiro Nakano,Akitomo Sugawara,Atsunori Yorozu,Takushi Dokiya,Shiro Saito,Masanori Fukushima,Shinsuke Kojima,Takashi Kikuchi,Hidetoshi Yamanaka,Shinichiroh Maruo

doi:10.1186/s13014-015-0532-3

Abstract

BackgroundThe 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).MethodsThe 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.ResultsSeed 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.ConclusionsThis 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.Trial registrationClinicalTrials.gov: NCT00534196

Highlights

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)
We report the results of our investigation of the incidence of seed migration with loose seeds by using J-POPS data, and of the factors associated with the occurrence of migration
The seed migration incidence was 21.6 % (PI: 22.7 %, permanent iodine-125 seed implantation (PI) + EBRT: 18.1 %), and it was higher in the PI group

Summary

Introduction

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). Transperineal permanent iodine-125 seed implantation (PI) for prostate cancer is widely accepted as a standard procedure for treating early-stage prostate cancer [1, 2]. It has shown favorable treatment outcomes [3, 4]. Various locations have been reported as sites of seed migration, including the lungs, abdomen, pelvic cavity, heart [14], vertebral venous plexus [15], kidneys [16], liver [17], and testicular veins [18]. As for the seed migration incidence, there are many reports of studies concerning only migration to the lungs, whereas only a few reports describe studies including migration to sites other than the lungs [9]

Methods

Results

Discussion

Conclusion