Prostate Cancer: Brachytherapy / Radioactive Seed Implantation
The number of men diagnosed with prostate cancer and the number of deaths from prostate cancer in the United States continue to increase each year. The American Cancer Society estimates that between 250-275,000 new cases of prostate cancer will be diagnosed in 1998. It is also estimated that prostate cancer will cause approximately 40,000 deaths in this country this year.
A number of treatment options exist for localized prostate cancer, namely, radical prostatectomy, radiation therapy, and observation. The merits of surgery and observation have been discussed in another article. This article will focus on a new option for delivering radiation to the prostate, BRACHYTHERAPY.
Q: What is Brachytherapy?
Dr. Green: Brachytherapy is a form of treatment whereby small “radioactive seeds” are implanted in the prostate. This requires a minor outpatient surgical procedure done with the assistance of transrectal ultrasound guidance.
Q: Is this a new treatment for prostate cancer?
Dr. Green: No. This procedure was initially introduced in the early ’70s by noted urologist Dr. Willet Whitmore at Sloan-Kettering Memorial Cancer Center in New York City. The technique was done with open surgery and the seed placement done without ultrasound assistance. The procedure was abandoned in the ’80s due to high failure rates for cure. The technique was refined and is now done with ultrasound guidance, which allows for more accurate placement of the seeds. The five year data has produced results equal to surgery or external beam radiation therapy in a select and limited number of patients. However, long term results have not accumulated; therefore, it is not possible to reach general conclusions about the benefits and risks of “modern brachytherapy”.
Q: How does radiation treat cancer?
Dr. Green: Tiny (about the size of a grain of rice) radioactive seeds of either Iodine-125 or Palladium-103 are placed into your prostate gland. These isotopes give off low energy X-rays which destroy the cancer in the prostate, but leave the rest of the body alone.
Q: How long does the radiation stay in my body?
Dr. Green: Iodine-125 and Palladium-103 give up about 90% of their radioactivity within a short time, six months and two months, respectively. By one year, the radioactivity can be considered gone.
Q: How many seeds does it take to treat the prostate?
Dr. Green: Depending upon the size of your prostate gland the number of seeds varies from 70-150. Fewer seeds for small glands and more seeds for large glands.
Q: How is the implant done?
Dr. Green: This procedure does not require a surgical incision. Instead, thin needles are passed into the prostate gland through the skin between the scrotum and the rectum. As the needles penetrate through the prostate, they are seen on the screen of the ultrasound machine and can be accurately guided to their predetermined positions within the prostate. When each needle is in its correct position in the prostate, the needle is slowly withdrawn while individual seeds are injected into the prostate gland. While the needles are being inserted, the ultrasound probe is in the rectum. Both the probe and the needles are removed when the procedure is completed.
Q: What will the procedure be like?
Dr. Green: The implant procedure takes about one hour. It is done as outpatient surgery in the operating room under spinal or general anesthesia. After the seeds have been implanted, a catheter will be placed temporarily in your bladder to drain urine. After the implant, you will go to the recovery room for approximately one to two hours. The urinary catheter will be removed prior to discharge.
Q: Does this procedure cause a lot of pain?
Dr. Green: No. There is little discomfort after the implant, although some mild soreness may be expected between the legs for a couple of days.
Q: What preparation is required?
Dr. Green: A transrectal ultrasound is done in the office to determine the volume of your prostate so that proper planning and seed acquisition for your implant can be done. If your prostate is very large, you may be placed on a monthly hormone shot for three months to shrink your prostate, thus making it easier to accomplish the implant.
Q: When can I return to normal activities?
Dr. Green: Soon. You should avoid heavy lifting and strenuous activity for the first 48-72 hours. If you feel well and are voiding satisfactorily after 72 hours you may resume your normal activity level.
Q: Is it safe for my family, friends, and co-workers to be around me after the implant?
Dr. Green: In general, yes – with the following caveats: small children and pregnant women may be more sensitive to the effects of radiation, and therefore, some additional precautions (remain six feet or more away, and children should not sit on the patient’s lap) should be in force during the first two months following an Iodine-125 implant and for one month following a Palladium-103 implant.
Both isotopes emit very low-energy radiation which does not travel far; in fact, the vast majority is stopped inside the prostate itself. However, very small amounts of radiation can reach other people from either a seed being passed in the urine or by a tiny amount of radiation that escapes from the prostate and travels through the air. The amount that escapes is so small that it is not considered a risk for most people, and there are no restrictions on a patient’s travel or physical contact with other adults.
Q: Can the seeds come out of the prostate after implantation?
Dr. Green: Yes. Rarely a seed may be expelled in the urine during the first couple of weeks post implant. The seed is a low energy beta emitter and should pose no health hazard. Because of this potential, implant patients are asked to strain their urine for the first week post implant, looking for seeds. If a seed is detected in the urine or on the floor, it should be picked up with tweezers and placed in the packet provided and returned to the medical center for proper disposal. Similarly, a seed occasionally passes with ejaculation during intercourse. For this reason it is recommended that a condom be used during intercourse for the first two weeks post implant. In general the amount of radiation exposure to the patient and those around him is minimal and does not represent a health hazard. Objects that a patient touches or items that are used do not become radioactive. Bodily wastes (urine and stool) are not radioactive.
Q: What are the side effects of “seed implantation”?
Dr. Green: You may experience some of the following:
- mild bleeding in the urine and per penis
- mild burning in the scrotum and perineum
- difficulty urinating requiring catherization
- (rarely) passing blood clots in the urine
- frequent urination
- burning with urination
- sense of urgency to void
- decreased force of stream
All of the above symptoms can be treated. These symptoms will gradually decrease as the seeds lose their strength, but may be present to some degree for 6-12 months after implantation. As with all medical procedures, there is a small chance that the symptoms may last longer or become permanent side effects.
Q: What follow-up is recommended?
Dr. Green: During the first week of your implant you will be asked to return for a CT scan and follow-up visit. The CT scan will enable the physicians to determine the exact position of each seed in the prostate. This is necessary in order to determine that your prostate gland is receiving the proper amount of radiation throughout the gland. On rare occasions, it may be necessary to give an additional amount of radiation with either external radiation or another implant.
Follow-up with your urologist and radiation oncologist will be done on a regular (approximately every 4-6 months during the first five years). Physical examination, blood tests including the PSA, and transrectal ultrasound will be done periodically during your follow-up visits.
Q: What are the benefits of Brachytherapy for localized prostate cancer?
Dr. Green: The benefits are as follows:
- proven effectiveness in treating localized prostate cancer.
- low risk of major complications.
- low risk of impotence.
- low risk of urinary incontinence.
- minor surgical procedure.
- minimal loss of service (time off from work and return to normal activity ).
Q: Who performs Brachytherapy and where can I receive a consultation?
Dr. Green: Brachytherapy is a team approach performed by a urologist and radiation oncologist working together for your benefit. The urologists at The Urology Institute perform Brachytherapy in conjuction with their associated radiation oncologist.
If you have localized prostate cancer and are interested in Brachytherapy as a treatment option, please call The Urology Institute at (972) 243-3368 for a consultation appointment.Request An Appointment