Patient's Guide to Radioactive Seed Implant for Treatment of Localized Prostate Cancer

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Introduction to Prostate Seed Implant

Over the past decade radioactive prostate seed implant has become a standard treatment for prostate cancer, and is now performed as frequently as surgery in the U.S. Prostate seed implant is a method of delivering high doses of radiation to the prostate with minimal effect on the surrounding organs, and is well tolerated by most men. Recent studies show that prostate seed implant in equally effective as surgery in curing localized prostate cancer. All treatments have some potential side effects and these should be discussed with the urologist and radiation oncologist who will be performing the procedure.

History of Prostate Seed Implant

Although prostate seed implantation has only recently become a standard treatment for prostate cancer, its historical development dates back almost 100 years. In 1903, Alexander Graham Bell wrote "...there is no reason why tiny fragments of radium sealed in a fine glass tube should not be inserted into the very heart of the cancer, thus acting directly upon the disease material. Would in not be worthwhile making experiments along this line?" In 1910, Young used intra-urethral radium for the treatment of prostate cancer. In 1930, Flocks first injected radioactive gold liquid into the prostate for the treatment of prostate cancer. In the early 1970s, physicians at Memorial Sloan Kettering Cancer Center in New York were the first to perform prostate seed implants, using iodine seeds. The procedure was performed through an abdominal incision with the seeds placed directly into the exposed prostate gland. In 1983 Holm performed the first "closed" implant, using needles and ultrasound guidance. In 1985 Ragde, Blasko, and Grimm modified Holm's technique and began to perform prostate seed implantation in Seattle. In 1988 they began to train other physicians, and seed implantation was soon to be widely accepted as an alternative approach for the treatment of localized prostate cancer.

radioactive prostate seed

Overview of Prostate Seed Implant

Prostate seed implantation, or brachytherapy, is a type of radiation treatment for prostate cancer. Small metal tubes, or "seeds", which contain radioactive material are placed into the prostate using small needles and ultrasound guidance. The seeds are tiny, and the radiation spreads only a small distance around each seed, so 80-120 seeds may be implanted in a single case in order to treat the entire prostate. Prostate seed implantation is a treatment for men with prostate cancer that is contained within the prostate or the area immediately around the prostate. This is determined by a number of tests, including digital exam, PSA, and biopsy results, and in some cases by bone scan, CT scan, or lymph node biopsy. Prostate seed implant alone is a good treatment for men with prostate cancer which is contained to the prostate itself. If there is a chance that the cancer has spread to tissue outside the prostate, then seed implantation may be performed in conjunction with external beam radiation, which can treat cancer cells in an area around the prostate. The decision to use external beam radiation and seeds or seeds alone is made by your doctors based on the cancer stage, volume, grade, and PSA.

In order for seed implantation to be effective the prostate volume must be less than 45 to 50 cubic centimeters. This can be estimated by digital exam and the prostate ultrasound done during the biopsy, but is most accurately measured by the special prostate ultrasound done for treatment planning. In some cases the prostate is clearly too big for seed implantation and your doctor will advise other treatments. In some cases the prostate can be shrunk to a small enough size by a medication that is given for 3-4 months. This medication (sometimes called hormonal therapy) is usually given as an injection. The same medication is also sometimes given to men with small prostates but larger or more aggressive cancers before doing the seed implant. The hormonal therapy shrinks the prostate and kills 90% of the cancer cells and can make the seed implantation more effective. You should discuss with your urologist and radiation oncologist whether treatment with hormonal therapy is necessary.

Three or four weeks prior to seed implantation you will have a special prostate ultrasound called a volume study. This is used to plan the implant and determine the number of seeds, seed strength, and seed placement. The volume study is usually done in the office and does not require any anesthesia and is not painful. The pictures from the volume study are traced into a computer and a 3-dimensional model of the prostate is created. The com-puter model is used to determine the number of seeds needed,seed strength, and seed placement.

The seed implant is done in the hospital with general or spinal anesthesia, and usually lasts 2 hours. During the procedure an ultrasound probe is placed in the rectum to help guide the needles which contain the seeds. Each needle is placed into the perineum, which is the area between the scrotum and the anus, and passed into the appropriate position in the prostate using ultrasound guidance. No incisions are made anywhere. At the end of the procedure cystoscopy (passage of a telescope through the penis into the bladder) is performed to be sure that no seeds have gone into the bladder. X-rays are taken in the operating room to check on seed placement. Most patients are in the recovery room for 1-2 hours after the procedure and then go home. Most patients will go home with a catheter in the bladder overnight, and will have it removed in the urologist's office the next day. Later in this booklet you will find information regarding possible side effects that can occur after the procedure. Most patients are able to return to normal daily activities within a few days of the implant.

Prostate seed implant is performed with needles placed between the legs into the prostate

About the Santa Cruz Prostate Seed Implant Program

Prostate seed implantation was first performed in Santa Cruz in April 1999 by Dr. Rosen and Dr. Sacks. Dr. Rosen first performed prostate seed implantation in 1995 at the Medical College of Wisconsin, where he was Chief of Urologic Oncology. Dr. Sacks, Dr. Meisel, and Dr.Kim have extensive experience with seed implantation for a variety of cancers, and have been performing prostate seed implantation with Dr. Rosen since 1999. All of the doctors received their training in prostate seed implantation at the Seattle Prostate Institute, where seed implantation was first popularized in the late 1980's.

Santa Cruz Treatment Results

The results of seed implantation in Santa Cruz are equal to those achieved at major prostate cancer centers around the country. More than 99% of our patients have been treated as outpatients, and less than 5% have had urinary retention (inability to urinate) beyond 1 week. We send our post-implant CT scans to Pro-Qura, Inc. (an offshoot of the Seattle Prostate Institute) for measurements of implant accuracy. They have certified that our implants meet their highest quality standard, and we have been named physician affiliates of the Seattle Prostate Institute in recognition of the quality of our implant program. The results of our implants from 11/99-5/02 are shown below. The goal of a V100 (percentage of the prostate that receives 100% of target dose) greater than 80% is shown in red.

results of prostate seed implant

Risks of Prostate Seed Implant


Seed implant has a lower risk of erectile dysfunction than other treatments for prostate cancer. A recent study showed that 76% of men who had seed implant maintained erections adequate for intercourse one year after implant, and 52% maintained adequate erections 5 years after implant. Cryotherapy (freezing the prostate) has the worst results of all prostate cancer treatments, with only 14% of men still potent after one year. In between are external beam radiation (68%), combined external beam radiation and seed implant (58%), nerve sparing radical prostatectomy (58%), and standard radical prostatectomy (30%). The risk of impotence after any of the prostate cancer treatments depends on patient age, with younger men having a better chance of maintaining good sexual function than men over 70. Men who are already noticing some problems with erections are more likely to have problems after any prostate cancer treatment. It is important to know that approximately 1/3 of men will notice no change at all in their sexual function after seed implant, one-third will notice some change, but still be able to function adequately, and one-third will have a significant decline in their sexual function over several years after seed implantation. Erections may be less firm than before, or more difficult to maintain. Most men will have much less volume to the ejaculate after seed implant, but the feeling of pleasure is usually unchanged.


Stress incontinence (leaking urine with coughing or straining) is extremely rare (< 1%) after prostate seed implant unless patients have had a prior prostate surgery (TURP). We do not recommend seed implant in most men who have had TURP.

Urinary Retention

Approximately 10% of men who have seed implant will have an episode of being unable to urinate within the first month after seed implant. Urinary retention is usually temporary (less than two weeks), with long-term inability to urinate occurring in 2% of men. The men who are at the highest risk of urinary retention are those with the largest prostates and the most urinary trouble before the implant. We do not recommend prostate seed implant in men with very large prostates or bothersome urinary symptoms.


Significant irritation of the rectum (proctitis) occurs in 2-3% of men who have seed implant alone, and 3-5% of men treated with combined radiation treatments. The symptoms of proctitis include rectal pain, blood in the stools, rectal urgency, and diarrhea. These symptoms are usually temporary and disappear within few weeks.

Urinary Symptoms

Most men who have prostate seed implants feel that their urination is changed for some time afterward, but eventually the urinary symptoms resolve and urination returns to normal. The most common side effects are a decreased force of stream, increased urinary frequency, urgency, and increased nighttime voids. These symptoms are mild in most men, but approximately one-third of men will have some "annoying" symptoms for the first 3 months after the implant. Most men need to take a medication to improve the flow of the urine for three months after the implant, and some men stay on the medication longer. By 6 months after the implant the urination has returned to normal in more than 90% of men. Less than 5% of men have prolonged prostate pain after the implant. This may cause pain during urination or pain in the penis, urethra, or perineum.

Recto-urethral fistula

Recto-urethral fistula is an opening that occurs between the rectum and the urethra due to breakdown of the tissue from radiation. It is estimated to occur in 0.1-2.4% of patients who undergo prostate seed implant. This is a devastating complication that usually requires colostomy or urinary diversion surgery, or both. Patients should avoid having biopsy or fulguration or laser treatment of the rectal wall under the prostate after radiation or prostate seed implant because this may lead to a fistula. Doctors who are planning to perform colonoscopy (examination of the colon with a telescope) should be reminded if a patient that has had a prostate seed implant.

Urethral Stricture

Approximately 5% of men may develop scarring of the urethra just below the prostate. This is more common in men who also receive external beam radiation in addition to prostate seed implant. For most of these men the urethral stricture is not a significant problem, but some men will require urethral dilation in the office or hospital because of decreased force of stream, pain during urination, or other symptoms. In some patients urethral stricture can be a long-term problem which does not have an easy solution, because the scarred tissue has been irradiated and does not heal like normal tissue.

Change in ejaculation

Most men will have much less semen when they ejaculate after prostate seed implant. The radiation from the seeds causes the prostate to produce much less fluid than prior to the seed implant. In most men the sensation of ejaculation is unchanged from prior to the implant. Rarely after prostate seed implant patients can experience pain in the prostate at the time of ejaculation. This is usually a temporary problem, but can be a long-term side effect for which there is not a specific treatment.

Radiation Safety Precautions After Prostate Seed Implant

Radiation safety is an understandable concern for patients after seed implantation. The type of radioactive seeds used for prostate implants emit low-energy radiation that spreads only a few millimeters around each seed. That is why so many seeds are implanted and why precise placement is necessary. Most of the radiation is given off into the prostate itself, but a small amount is given off to structures close to the prostate such as the bladder, rectum, and urethra. Minimal radiation escapes from the body, and your bodily wastes (urine, stool) are NOT radioactive. The radiation exposure to spouses after seed implant is less than half the amount of radiation that they receive from the sun in one year, and is much less than the amount of radiation received on a cross-country airplane trip. For these reasons we do not recommend that wives and husbands sleep in separate beds after the implant. The following precautions should be followed after the seed implant:

What to Expect after Prostate Seed Implant

The Early Postoperative Period (1-7 Days)

I have bruising on my scrotum and it hurts a little to sit down.

During the first few days you may have some bruising on the perineum (the place between your anus and your scrotum) or on the scrotum itself. This is caused by the needles (usually 20-30) which are used to place the seeds. This will resolve on its own and usually does not cause any discomfort. Rarely a larger hematoma may form on the perineum and this will cause some discomfort with sitting. This should be brought to the doctors attention, but it will resolve on its own.

I have burning with urination and blood in the urine.

Most patients will have some burning with urination for the first few days after the implant. This is due to irritation from the catheter and is not caused by urinary infection or the radiation. You should continue to use Pyridium for as long as necessary but the burning rarely lasts beyond the first few days. Some patients will have blood in the urine for the first few days after the implant. This will stop on its own but you should refrain from any strenuous activity until the urine is clear and you should drink plenty of liquids to keep the bladder flushed out.

I feel like I am having trouble passing my urine.

Some patients will have trouble passing urine after the catheter is removed due to swelling in the prostate. You should call Dr. Rosen if you cannot pass urine within 6 hours of catheter removal or any time if you are having trouble passing your urine. Some patients may require a catheter for 1 week or more after seed implantation.

The First Month (1-4 weeks)

I am starting to have urinary symptoms 2 weeks after the implant.

Most patients will start to have some bladder irritation at roughly 2 weeks after the implant. This is caused by the radiation and will last 6-12 weeks in most cases. Patients may experience frequent urination, burning, a sense of urgency when they need to pass urine, or a weaker urinary stream. These are usually self-limited and will resolve completely.

I needed to have a catheter replaced 3 weeks after the implant.

Approximately 10% of patients will go into urinary retention in the first month after the implant. They may not be able to pass urine at all or may be urinating frequently and emptying the bladder very poorly. This is caused by swelling of the prostate gland and muscle spasm caused by the radiation. In most cases the catheter can be removed within 1 week but in some cases it takes much longer before adequate urination is possible.

I passed a small amount of blood in my stool and I have diarrhea.

Some patients will have irritation of the rectum after seed implant. This can cause blood in the stool, diarrhea, or rectal pain. These symptoms are usually not severe and will resolve with time. Patients should avoid strenuous activity if they see blood in the stool. Diarrhea can be managed with bulking agents such as Metamucil, or the doctor can prescribe medication.

Long Term Side Effects (Beyond the first month)

Urinary Side Effects

Approximately 1/3 of men will say that their urination is not completely back to normal by 3 months after the implant. The symptoms are usually minor but might be frequent urination, getting up at night, or a slower stream. Some patients may experience a small amount of incontinence because their bladder starts to empty before they can get to the toilet. Incontinence with straining, coughing, or exercise is extremely rare after seed implant unless patients have had a transurethral prostate resection before or after the seed implant. You should discuss any symptoms with the doctor.

Sexual Side Effects

As many as 50% of men will notice some change in the quality of their erections over 5 years after the external radiation or prostate seed implant. This may be a decrease in the firmness of the erection or difficulty maintaining an erection. Nevertheless, most men maintain erections that are adequate for satisfying intercourse. The change in the erections may be caused by radiation, but many men in the prostate cancer age group will have a change in their erections over a 5 year period even without external radiation or seed implant. Approximately 25% of men will experience a decrease in their erections within the first 2 years after seed implant to the point that they are not adequate for intercourse. Please discuss any problems achieving or maintaining an erection with your urologist, because there are treatments which may help. Most patients will notice a decrease in the volume of semen when they ejaculate after prostate seed implantation. This is caused by scarring of the ejaculatory ducts as they pass through the prostate and decreased fluid production by the prostate. This is not treatable but does not usually change the feeling of orgasm or diminish sexual pleasure.

Intestinal Side Effects
The chance of long-term intestinal side effects is low after seed implant. Some patients will have occasional blood in their stools, but significant pain, rectal urgency, diarrhea, or other problems are rare. These side effects should be discussed with the radiation oncologist.

Prostate Volume Study Instructions

You are scheduled to have a prostate ultrasound volume study which will be used to plan your prostate seed implantation. It is scheduled for ___________ at _________ at Santa Cruz Radiation Oncology. Please follow these instructions in preparation for the volume study:

If you have any questions please call Dr. Rosen's office at 476-2626 or 728-4227.

Prostate Seed Implant Pre-Operative Instructions

Your prostate seed implant surgery has been scheduled on ____________ at ________at Dominican Santa Cruz Hospital. Please report to the admitting window in the lobby 2 hours prior to the procedure. The surgery is planned as an outpatient procedure, although rarely patients are admitted to the hospital overnight if necessary. The procedure takes around 2 hours and most patients are in the recovery area for 1-2 hours after the procedure. The following are special instructions to follow before your seed implant procedure.

Preoperative Instructions:

If you have any questions about these instructions please call Dr. Rosen at 476-2626 or your Radiation Oncologist at 462-3050.

Prostate Seed Implant Post-Operative Instructions


Regular, unless you are on a special diet for other reasons.


Avoid heavy lifting or strenuous physical activity for the first two days after the procedure. At that time you may return to your normal activity level if the urine is clear and you feel fine. If the urine is still bloody you should rest and drink plenty of fluids until it is clear, and then you may resume normal activity.



All patients are sent home from the hospital with a catheter and a leg bag. You should make an appointment to have the catheter removed the next day in Dr. Rosen's office. You will then be seen one week after the implant by Dr. Rosen to be certain that you are passing your urine without any problems. Santa Cruz Radiation Oncology will contact you to schedule a post-implant CT scan of the prostate, usually one month after the implant. This is a quality control measure to be certain that the proper dose of radiation has been given to the prostate. You will usually be seen by Dr. Rosen 6 weeks after the implant for a checkup, but you should call to be seen sooner if you are having trouble urinating or any other side effects.

Prostate Seed Implant Followup

The goal of prostate seed implantation is to cure the prostate cancer without causing significant long-term side effects. After the seed implant you will need regular check-ups to determine whether the procedure has been successful in meeting these goals. These check-ups are done more often during the first 2 years after the seed implantation and then less frequently in the years that follow. Because prostate cancer is so slow growing these checkups will extend beyond 5 years after the procedure.

The two main tests to assess the success of the procedure are the digital rectal exam and the PSA blood test. The digital exam can determine the size of the prostate; if the cancer was palpable before the implant the exam can detect change in size, or complete resolution, of the abnormality. The PSA test is the best indicator of the success of the procedure. The PSA drops slowly after seed implant and can take 2-3 years to reach a low level. Because the prostate is not completely removed the PSA will usually remain above zero after the implant, but we hope to see the PSA fall below 1.0 or even below 0.5. In many patients the PSA may rise during the second year after the implant and then go back down; this is not usually a reason to worry. If the PSA increases on three successive tests after the seed implant it is usually a sign that there are some active cancer cells somewhere in your body, and further testing needs to be done.

Most patients have a PSA and office visit every three months for the first year after the implant. From one to five years after the implant a PSA and exam and symptom check are performed every six months. After five years patients are usually seen once a year. More frequent checkups may be required if you have any side-effects from the implant. You will need a PSA blood test one week before each appointment starting 3 months after the implant. Please contact Dr. Rosen if you have any questions regarding the follow-up and please make sure that we have the name of your regular medical doctor so we can keep him or her informed of your progress.