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

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

Search and removal of radioactive seeds: another application of postmortem computed tomography prior to autopsy

“…Conventional pelvic radiography may help to detect these seeds in the pelvis but it is not sufficient for detection of migrated seeds in organs such as the lungs (Case 2, 3), or the heart (Case 3). Such migration is frequently observed in patients with these implants (1.7 to 69.4 %) [15] and occurs in many sites of the body including the liver, kidneys, and vertebral column [16][17][18]. Additionally, recent reports show that permanent brachytherapy can now be used to treat cancers in many other parts of the body, which increases the challenge of finding the seeds [19][20][21].…”

Deformable registration of x ray and MRI for postimplant dosimetry in low dose rate prostate brachytherapy

“…Seeds at the prostate periphery, particularly within the seminal vesicles, base, and apex may migrate following insertion. 52 Visual inspection of the seeds with TREs >5 mm suggest that most of the apparent registration errors occurred in these regions prone to seed migration. For clinical postimplant dosimetry, x rays used for seed reconstruction will typically be acquired on the same day as the MRI to mitigate potential seed migration and reduce the maximum TREs, similar to the CT/MRI approach.…”

“…In this study, we considered seeds implanted within the prostate and outside of the prostate within 1 cm of the prostate periphery, which commonly arise in peripherally loaded treatment plans. Seeds at the prostate periphery, particularly within the seminal vesicles, base, and apex may migrate following insertion . Visual inspection of the seeds with TREs >5 mm suggest that most of the apparent registration errors occurred in these regions prone to seed migration.…”

Toxicity in patients treated with permanent prostate brachytherapy using intraoperatively built custom-linked seeds versus loose seeds

“…In prostate BT, optimal planning after implantation is not always achieved due to prostate volume changes or seeds loss [ 2 ]. In addition, periprostatic and extra-glandular seeds placement may cause source migration in a small percentage of patients [ 3 , 4 ]. One way to improve seed placement is the use of stranded seeds called “intraoperatively built custom-linked seeds (IBCLS)” in an opposition to loose seeds (LS).…”