Brachytherapy for Prostate Cancer

Brachytherapy treatment for prostate cancer is “internal radiation” delivered very close to the target tissues. The radiation source is usually implanted using needles that are introduced through the perineum, the area between the rectum and the scrotum, under ultrasound guidance. Brachytherapy sources may be implanted temporarily or permanently.

Your radiation oncologist will discuss the many brachytherapy treatment options available at Beaumont, and determine which would be best for you.

Feasibility of a brachytherapy implant

Not every prostate cancer patient is a candidate for brachytherapy. Patients undergo an ultrasound examination to assess the size of the prostate, the width between the pubic bones and the position of the prostrate and urethra. After the ultrasound, your doctor will tell you whether an implant is feasible.

In some cases, doctors recommend taking hormone medications for a short period to shrink the prostate and make implantation easier.

Patients who have had transurethral resection of the prostate (TURP) or very frequent or urgent urination before radiotherapy may not be good candidates for brachytherapy.

Brachytherapy given alone (monotherapy) is usually reserved for low-risk, early-stage cancer confined to the prostate.

For higher-risk cancer, brachytherapy is sometimes combined with external beam radiation therapy (a brachytherapy “boost”).

Implant surgery

Prostate implants are inserted during a minor surgical procedure performed using a spinal anesthetic rather than general anesthesia. Some patients stay in the hospital overnight, depending on whether the implant is temporary or permanent. Many patients will return to work or normal activities within a day to a week.


Low-risk prostate cancer may be treated with brachytherapy alone (monotherapy). The criteria for monotherapy include:

  • low PSA, usually 10 or less
  • low Gleason score, usually 6 or less
  • low stage, usually T2a or less

Your doctor will talk with you about the possibility of monotherapy implants, which can be temporary or permanent.

Permanent seed implants (low-dose rate brachytherapy) – Low-dose brachytherapy treatments can be delivered with iodine or palladium seeds. There is no evidence that one type is better than the other, though the characteristics (radiation energy and half-life) of the two types are somewhat different. Beaumont uses palladium (Pd-103) seeds. Pd-103 has a half-life of about 17 days, meaning that approximately half the dose is delivered every 17 days. After a few months, almost all the radiation dose has been delivered to the prostate. The seeds remain in the prostate and eventually will lose their radioactivity.

Seeds are implanted during an outpatient procedure. Typically, patients arrive early in the morning, undergo the procedure and leave the hospital in the evening after they have recovered from anesthesia and are able to urinate. Several medications administered after the implant prevent or reduce side effects or infection. Patients return a few weeks after the procedure for a CT scan to further evaluate the implant.

Temporary seed implants (high-dose-rate brachytherapy) – High-dose brachytherapy treatments use a temporary seed implant containing iridium 192 (Ir-192). Because no permanent seeds are left inside the body, there are no immediate radiation precautions. Plastic needles/catheters are implanted much like permanent implants under spinal anesthesia. However, the catheters are kept in place to deliver a series of two to four radiation treatments over one to two days, with about six hours between treatments. During this time you will stay in the hospital overnight.

After the physician has placed the catheters in the prostate, each catheter will be connected to a radiation machine. A radiation source connected to the machine will go in and out of each catheter to deliver the radiation for a specified period of time, usually about 15 to 20 minutes. After the radiation has been delivered, the source returns to the machine and you will not be radioactive. The catheters are held in place by a template and a few stitches until all treatments are complete. 

While the template and catheters are in the prostate, you will be given epidural medication for pain control and will be required to lie on your back to avoid kinking or shifting the catheters. After the second or last treatment, the catheters will be removed. You will be discharged from the hospital when you are able to urinate. Several medications will be administered after implant to prevent or reduce side effects and infection.

Combination brachytherapy treatment

3D conformal external beam radiotherapy with high-dose-rate brachytherapy boost (HDR boost) – For patients with higher-risk prostate cancer, 3D external beam radiotherapy is combined with brachytherapy. The external radiation is designed to treat the lymph nodes and the tissue around the prostate, while the high-dose-rate brachytherapy gives an extra boost of radiation to the prostate. Often the external radiation is given for several treatments first, and then combined with several high-dose-rate implants performed on specified days during the course of radiation. The external radiation usually takes about five weeks. This type of combination therapy might also be used with a short or long course of hormone therapy.

The HDR boost is very similar to the HDR monotherapy described previously, except it does not require an overnight stay. The catheter is placed, the radiation given, the catheter removed and patient sent home once he is able to urinate. If two HDR boosts are prescribed, they will be performed as separate procedures several weeks apart.

Brachytherapy side effects

Side effects from brachytherapy treatments are similar to those for external beam radiation therapy. With a seed implant, side effects might start two to four weeks after the implant, peaking at about two months. In general, brachytherapy treatment for prostate cancer tends to have more urinary side effects (frequency, urgency, burning) than rectal effects, which are more common with external beam radiation. It is not uncommon to pass some blood in the urine or semen shortly after an implant. Because brachytherapy requires a surgical procedure, it carries the risks of infection or bleeding that can occur with any surgery, although these are very rare.