|Introduction To Prostate Seed Implants (Brachytherapy)|
The choice of treatment for prostate cancer has to be individualized, and is often based on many factors including age, basic general health, the potential of the cancer to spread to surrounding tissue and bone and the aggressiveness of the cancer as well as the patient's preference for treatment. These issues should be thoroughly discussed with your radiation oncologist as well as with your family. This page will assume you have discussed these options with your physician and that brachytherapy is going to be an option for your course of treatment. What follows is a discussion of radioactive seed implantation into the prostate using Palladium 103 (Pd-103), Iodine 125 (I-125) or Cesium 131 (Cs-131). Our radiation oncologist's currently perform seed implants in the OR at Huntington Hospital in Huntington, NY and St. Catherine of Siena Medical Center in Smithtown NY as an outpatient procedure.
Click here to see what a few Radiation Oncologists have to say about brachytherapy seed implantation with Cesium-131
Your Prostate Brachytherapy Treatment Team
From Left to Right: Jeffrey Musmacher, Lawrence Rumpf & Dr. Richard T. Byrnes
Prostate cancer is a disease of the prostate tissue cells. Unlike normal cells that reproduce in order to replace worm-out tissue, cancer cells grow uncontrollably and have the potential not only to destroy the prostate, but also can spread to other organs causing unpleasant symptoms and possibly even death at an advanced stage of prostate cancer. Suspicion of prostate cancer is detected by a digital rectal exam and/or a blood test called PSA (Prostate Specific Antigen). Finding malignant cells is performed either by a biopsy or at the time of a TURP procedure makes the diagnosis. If the prostate cancer is determined to be localized with in the prostate, a number of treatment options including radical prostatectomy, external beam radiation therapy with IMRT/IGRT or brachytherapy may be offered.
How Dose Radiation Treat Prostate Cancer?
When radioactive seeds are placed into the prostate, they emit low energy x-rays which is used to destroy the cancer. The radioactivity is emitted only for a short period of time and, in fact, by one year the radioactivity is gone. The actual seeds are about the size of a grain of rice and, depending on the size of the prostate, your team may implant somewhere between 50 and 100 seeds (dependant on the overall size of your gland and the isotope used). The entire prostate is treated in order to assure that even small amounts of cancer within the prostate that may have been missed during a biopsy, are effectively treated. Since the radiation emitted from each seed does not normally reach nearby organs, it is generally a fairly safe form of radiation therapy. The implant procedure does not require an actual surgical incision. Instead, the seeds are placed into the prostate gland, using 18 gauge needles guided by ultrasound, through the skin between the scrotum and anus. The ultrasound guidance allows for an even and accurate placement of seeds to treat the whole prostate. The individual seeds are injected into the prostate gland as the needles are removed. The seeds remain permanently, but become inactive as they cycle through their half-lives.
How Is This Procedure Done?
Before you undergo the actual implantation of the seeds, a map of the prostate is created from a transrectal ultrasound scan of the prostate, this is know as a Prostate Volume Study. This study will determine the volume and the shape of your prostate. A plan will be generated to determine the number of seeds needed to treat the cancer and the pattern of seeds that should be used. This is done with the assistance of a sophisticated computer program, and is modeled for each individual patient. The actual implant procedure is done in an Operating Room and takes 45 minutes to one hour. General anesthesia is most often used but in a case where a patient is unable to receive general, spinal anesthesia is used to provides numbness from the waist down. Once the seeds have been implanted, a catheter may be placed into the bladder through the opening of the penis to drain the urine. From the Operating Room you will go to the Recovery Room for several hours until normal sensation has returned. An ice bag is usually placed between the legs to reduce swelling in the implant area. The catheter may be removed prior to your discharge from the hospital. There will be some discomfort following the procedure and pain medication is available if needed. In general, you will be asked not to drive a car for at least 12-24 hours, but you may resume normal eating. Is some cases, blood in the urine can be noted for usually up to 24hrs. To avoid any chance of significant bleeding, you should avoid heavy lifting or strenuous physical activities for the first two days following the implant. Usually, by the third day normal activity may be resumed.
Seeds Implants As The Only Treatment
This approach takes maximum advantage of the confined, high dose radiation that seeds can provide. The use of seeds alone is best suited for low risk patients with very early stage prostate cancer, usually defined as those with a stage T1 or T2 cancer, a Gleason score of 2-6, and a PSA level of 10 or below. The cure rate for these patients is very high and it has demonstrated that there is no benefit to be gained by the addition of other therapies. Moreover, using seeds as the only treatment tends to involve the least troublesome side effects. It is clearly the most convenient and least disruptive treatment, involving only a single, 1-hour outpatient procedure. Thanks to PSA testing and the increasing awareness of the importance of early diagnosis, most of the men cared for with seed implants fall into the low risk group and receive implantation as their only treatment.
Combining Seed Implants With Other Treatments
Seeds Combined With External Beam Radiation
This combination treatment is generally recommended for intermediate and high risk patients, those with a somewhat higher chance of having cancer outside of the prostate. Generally speaking, intermediate risk patients are those with one of the following: a stage T3 cancer, a Gleason score of 7-10, or a PSA level of 10 or more. High risk patients meet two of these criteria. With this combination treatment, patients first undergo a 5-week course of daily external beam radiation treatments. The implant is performed within a 2-4 weeks period after the end of the external beam therapy. This approach is obviously less convenient for patients and there are slightly more rectal side effects due to the external beam radiation. However, in terms of protection against the possible spread of cancer outside of the prostate, the addition of external beam therapy provides an effective dose of radiation to areas around the prostate that are beyond the reach of the radiation emitted by seeds alone.
Adding Hormone Therapy
Also referred to as "hormone deprivation", "anti-androgen therapy", and "complete hormone block", is a form of treatment using chemical agents to lower the levels of testosterone in the blood. Testosterone, the male sex hormone responsible for the development of masculine characteristics, also has the effect of promoting the growth of certain prostate cancer cells. Hormonal therapy is principally used as a life-prolonging treatment for patients with metastatic prostate cancer at the time of diagnosis, or for patients whose cancer reappears following earlier attempts at cure with surgery or radiation. Hormone Therapy may also be used to help reduce the over-all size of a larger prostate gland to help make it more suitable for brachytherapy treatment.
Advantages & Disadvantages Of Seed Implantation
The main advantage thus far is that patients who have seed implants generally seem to do as well as far as controlling the prostate cancer as patients who have had radical prostatectomy or external beam radiation for up to 12 years following the procedure. In addition, seed implantation is performed as a outpatient procedure and normal activities can be resumed within a few days. The seeds can deliver up to twice as much radiation, and with fewer side effects than external beam radiation. Incontinence is extremely rare following implantation. Impotence or loss of sexual function occurs in fewer than 15% of patients under the age of 70. Older patients do well with this procedure since it is less stressful than surgery or external radiation. The main disadvantage of seed implantation is that there is no information yet available on the effectiveness of the implant treatment beyond twelve years. The current data looks good, but the long-term outcome is not yet known.
What About Radiation Safety?
Palladium-103 (Pd-103), Iodine-125 (I-125) and Cesium-131 (Cs-131) emit a very low energy radiation. While this radiation does not travel far from the prostate, there are some general precautions, Contact with small children or pregnant women can occur, but they should remain 3 - 6 feet away as you wanted to limit close contact to a maximum of 5 minutes per day. Children should not sit on your lap during the first 60 days following I-125, 30 days following Pd-103 and 15 days following Cs-131. Your spouse may sleep in the same bed if there is no risk of pregnancy. Rarely, a seed may be lost during urination. This usually occurs during the first week following the implant procedure.
What Are The Side-Effects From Seed Implantation?
Initially after therapy, discomfort behind the scrotum may be noted as a result of the needles used to place the seeds. In addition, some blood can be noticed in the urine. Excessive bleeding or severe pain should prompt a call to your urologist. Some burning during urination is not an uncommon side effect that can be battled by increasing your intake of water and eliminating items that are caffeinated or acidic for a few weeks following your procedure. Difficulty with urination should again lead to a phone call to your urologist. The radiation itself can cause urinary frequency, burning with urination and urgency of urination. A few patients have experienced fullness in their rectum or a sense of constipation. These rare symptoms usually resolve themselves after a few months. Anti-inflammatory medications and antibiotics are generally provided to minimize such symptoms following the procedure.
A CAT scan of your pelvis will be performed 3-4 weeks following the brachytherapy procedure to determine the exact position of each seed in the prostate. You will than see your radiation oncologist approximately 2 weeks after your scan to review the results. In general, every 3-6 months for the first five years, a digital rectal exam and a PSA blood test will be recommended to track your progress.