Brachytherapy Seed Migration

Brachytherapy may be part of your treatment plan for prostate cancer. Low dose rate (LDR) brachytherapy or high dose rate (HDR) brachytherapy can be used. One possible side effect of LDR brachytherapy is seed migration. Seed migration is when a seed from brachytherapy moves out of the prostate where it was placed. 

Seeds can move because there are many veins that surround and drain the prostate gland. If your seed migrates, it often happens in the first few days after the seeds were placed.

Where do the seeds go if they migrate?

The seeds either move to other areas of your body or leave your body.

• Seeds can move through the veins around the prostate and travel through the bloodstream to places like the lung or bladder. You may not know a seed migrated because you can’t feel it and it does not cause side effects right away. It is often found when you have a scan at your follow-up appointment.
• Seeds can also come out in your urine or during ejaculation. Your provider may ask you not to have sex for a few days after the seeds have been placed and to use a condom the first few times you ejaculate. They may also ask you to watch for seeds when you urinate (void or pee). If you think a seed came out, do not pick it up. Contact your provider and they will tell you what to do with the seed. They may ask you to use tweezers to pick up the seed, wrap it in foil, and return it to them.

How is seed migration managed?

If one of your seeds migrates it will not change how well your treatment works. There are usually more than one hundred seeds placed in the prostate and there is enough radiation to treat your cancer.

When should I call my care team?

Call your care provider if you find a seed after having brachytherapy or if you have any new pain. While it is rare, there is a chance that a seed can migrate to your heart. If you have chest pain let your provider know.