Brachytherapy Seed Migration
Brachytherapy can be used to treat prostate cancer. One possible side effect is seeds leaving the prostate and moving to another part of the body, most often the bladder or lung. This can happen due to the extensive vasculature of the prostate capsule. Seeds can move out of the prostate through the bloodstream.
This movement often takes place in the days right after the seeds were placed. Seed migration can be found on chest x-rays or it is discovered in the toilet after a man has urinated. Sometimes a seed will pass during ejaculation. The percentage of seeds that migrate is generally very small (one or two of hundreds of seeds).
How is it managed?
Unless there is concern that a significant number of seeds have migrated, seed migration is thought to be a harmless event. If a seed is passed during urination or ejaculation it is best to use tweezers to retrieve the seed, wrap it in foil and return it to your provider. Men should be instructed to use a condom during sexual acts involving ejaculation while being treated with brachytherapy.
When should I contact my care team?
Contact your care provider if you find a seed after having had brachytherapy. You may not know if a seed has migrated since it may not have any immediate effect. However, if you have a sudden onset of new pain, contact your provider right away.
American Cancer Society. Radiation Therapy for Prostate Cancer. 2019. Found at: https://www.cancer.org/cancer/prostate-cancer/treating/radiation-therapy.html
Ankem MK, DeCarvalho VS, Harangozo AM, Hartanto VH, Perrotti M, Han Kr, Shih WJ, Malka E, White EC, Maggio R, Ioffreda R, Goldsmith JW, Weiss RE. Implications of radioactive seed migration to the lungs after prostate brachytherapy. Urology. 2002:59(4) 555-559.
Sugawara A, Nakashima J, Kunieda E, Nagata H, Mizuno R, Seki S, Shiraishi Y, Kouta R, Oya M, Shigematsu. Incidence of seed migration to the chest, abdomen and pelvis after transperineal interstitial prostate brachytherapy with loose seeds. Radiation Oncology. 2011:6(130).