Prostate Seed Implants: A Promising Treatment For Prostate Cancer

Prostate brachytherapy (pronounced bray-kee-ther-uh-pee), the implantation of radioactive seeds into the prostate gland, is one of the standard methods of successfully treating prostate cancer. The tiny radioactive seeds are smaller than grains of rice.

A prostate seed implant may be the only type of radiation therapy needed by a man with low-risk prostate cancer or it may be prescribed in addition to external beam radiation therapy in men with intermediate- and high- risk prostate cancer. The goal is to eradicate cancer cells while preserving healthy, surrounding tissue, such as the bladder, the urethra (the tube that connects the bladder to the penis), and the rectum.

The advantages of prostate seed implants are significant. Fist, the procedure requires only minor surgery, usually causing fewer side effects than other treatments. Also, it is generally a same day, outpatient procedure. Men usually are able to return to work within several days, as long as they feel well enough. In addition, recent reports suggest that the procedure, when performed on properly selected men, is at least as effective as surgery to cure prostate cancer. Radiation exposure to other people is minimal, so restrictions do not apply unless the man is returning to a setting where a young child or pregnant woman is present.

Treatment Planning
Men undergo a pre-implant ultrasound study to determine where the radioactive seeds (and the needles to implant them) should be placed. A transrectal ultrasound, wherein an ultrasound probe is carefully positioned in the rectum to view the entire prostate, is performed. Images of the prostate are taken and are transferred to a special treatment planning computer, which evaluates the position of the prostate and generates a three-dimensional plan that dictates the precise placement of the seeds.

Preparation for the Procedure
Most candidates for prostate brachytherapy undergo blood tests, a chest x-ray and an EKG several days prior to the implant, in order to be approved for anesthesia. On the morning of the procedure, men receive an enema to help optimize the quality of the transrectal ultrasound images. In addition, blood thinners are discontinued several days prior to the procedure to help diminish the risk of bleeding.

Day of the Procedure
Typically, men who are scheduled to undergo seed placement arrive early in the morning. Next, the man is taken to the operating room for the procedure, where he undergoes either general or spinal anesthesia. Then, the radiation oncologist and the urologist work as a team to implant the seeds into the prostate, using transrectal ultrasound to guide the placement.

The Implant Process
Using the treatment plan and fluoroscopy (real-time x-ray), the radiation oncologist places the seeds within the prostate. The entire procedure usually takes less than one hour. After the seed placement, the urologist performs a cystoscopy (a procedure in which a slender, flexible, fiber optic scope is inserted from the penis into the bladder), to look for and remove any seeds that dislodged in the bladder or the urethra. Within the few next days, a CT scan is obtained to verify the placement of the seeds.

Prostate Seed Implants: Recovery
Because prostate implants do not involve major surgery, side effects are rarely severe. The most common side effects reported by men after prostate seed implants are:

? Urinary frequency (60-70%)
? Urinary burning (50%)
? Urinary urgency (50%)
? Erectile dysfunction (30%)
? Blood in the urine (20-30%)
? Increased bowel movements and bowel urgency (5%)
? Fatigue (20%)
? Pelvic pain (20%)
? The need for temporary catheter placement (10-15%)
? Urinary incontinence (less than 1%)

In addition, up to 20 percent of men are found to have seed migration into their lungs. However, no detrimental effects have been reported. Infrequently, men have required trans-urethral resection, the ?scraping? of the prostate gland via the penis, to relieve urinary obstruction after the seed placement.

Follow-Up
Men who undergo prostate brachytherapy report for follow-up visits four weeks after the procedure and every three months thereafter. A PSA blood test and a physical exam are performed to assess the status of the prostate.

The good news is that prostate seed implants are usually successful at controlling prostate cancer within the gland. Such local control of disease correlates with rendering men free from prostate cancer.

Dr. Kornnmehl is a board certified radiation oncologist and author of the critically acclaimed consumer health book, ?The Best News About Radiation Oncology? (M. Evans, 2004). Her website is http://www.RTSupportDoc.com.