BRACHYTHERAPY FOR PROSTATE CANCER - a patient's guide
Dr John H L  Matthews -Cancer Specialist

Overview

This is one of the three methods used to treat early localised prostate cancer, with the aim of cure.

The alternative methods include radical prostatectomy or external beam radiation.

Most doctors believe these methods offer a similar chance of cure for early prostate cancer ,although they have never been properly compared in randomised trials.

The choice of treatment usually comes down to a comparison based on likely side effects , risks and complications. Convenience and quality of life issues play an important role in choice of treatment.

This choice is best made after discussion of the options with your doctor and urologist/oncologist.

With this method radioactive iodine125 seeds are implanted into the prostate gland.

The advantage of using this technique is that it delivers about one and a half times the dose of radiation to the prostate as external beam radiation alone, which should theoretically result in a better chance of cure.

The implant is done by a specialist consultant radiation oncologist and specialist consultant urologist as a combined procedure.

It has been used increasingly in America in recent years,and is available in some other countries (including New-Zealand)

Procedure

You will attend for this procedure after preliminary investigations and planning procedures are complete. These include a CT scan and transrectal ultrasound. These are performed to record the shape and size of the prostate and to ensure the needles can be inserted without difficulty. With this information about the prostate it is then possible to accurately determine the number and position of seeds required.

Just prior to your implant you will be required to have an electrocardiogram (a measurement of the electrical activity of your heart) if you are 60 years or older or have a history of heart disease, and also some blood tests.

The day prior to your implant you will be required to be on a clear liquid diet and to give yourself some enemas. The doctor or nurse will explain this to you.

The implant is performed under a spinal or general anaesthetic. An ultrasound probe is inserted into the rectum so that preloaded seeds can be inserted through the perineum (the skin between the back of the scrotum and the front of the anus) into the prostate under the guidance of ultrasound and x-rays (fluoroscopy). Once your Doctors are satisfied with the position of the seeds a catheter is put in place to drain the bladder. This is usually removed a few hours after the procedure and you will be discharged within 24 hours. This is a "closed" procedure with no open wound and there is minimal discomfort.

About 2 to 3 weeks after your implant you will have a further CT scan to check the position of the seeds.

You will be given supplementary guidelines on diet, radiation protection and appropriate medications if you have the implant.

In patients who have a risk of microscopic spread around the prostate a combined treatment of external beam radiotherapy and an implant may be recommended.

Discomforts and Risks

1. Post implant

This procedure may result in slight bleeding beneath the scrotum, blood in the urine and some bruising and tenderness immediately after surgery.

After the catheter is removed it is normal to experience some burning with urination. It is usual to pass blood in the urine for a few days. A small number of men may need a catheter left in for a few days and very occasionally more prolonged catheterisation may be required.

2. Usual Side Effects

General side effects from the radiation are unusual because the radiation is limited to such a small area of the body. Fatigue can occur but is usually minimal. No hair loss, nausea, vomiting or diarrhoea should occur.

Following the implant the usual side effects are due to the irritation of the the urinary tract and the rectum. Some urinary frequency and urgency and difficulty in passing urine are expected. Prostate or bladder infections and urinary retention can occur. Drinking plenty of water helps to flush the bladder. There may be a temporary increase in bowel movement frequency and a feeling of irritation when having a bowel movement. Some men get a brief pain or burning sensation with ejaculation and there may be less fluid.

These urinary, rectal and sexual symptoms reach a peak at about 4 to 6 weeks after the implant and gradually subside over the next few months. However the radiation side effects are not usually troublesome enough to keep patients from their usual activities and men working full time prior to the implant are unlikely to miss work because of side effects.

3. Complications

The usual side effects of implant radiation are mild and reversible and in most patients these symptoms settle completely. However there is a small chance of more serious ongoing side effects. Urinary incontinence (difficulty holding onto one's urine) is very uncommon and usually occurs in less than one percent of men. Intermittent rectal bleeding may result from inflammation of a small part of the rectum. The bleeding occurs in about five percent of men and is usually minor showing up as a bright spot of blood on the toilet paper.

More serious rectal complications occur in less than one percent of men and include ulceration of the rectum overlying the prostate which usually heals within 1 to 2 years. The radiation implant is likely to cause infertility and men considering having children in the future should sperm bank before the implant. Sexual impotence (the loss of erections) occurs in fifteen to fifty percent of men. The risk of this depends on one's age at the time of implant and men under the age of 60 years are much more likely to continue to have erections.

Overall the risk of serious complications is lower than with either external beam radiotherapy or radical surgery and is generally less than five percent . If symptoms bother you, medication from your doctor may be helpful.

Follow up with your Urologist and Radiation Oncologist will be done on a regular basis.

4. Radiation Risks

As the seeds are implanted directly into the prostate gland only a very small amount of radiation is present outside the body. In fact this radiation is much less than the background radiation in the ground and atmosphere. However, sensible precautions are advised to minimise any possible risk to others.

For eight weeks after the implant children should not be allowed to sit on your lap. Pregnant women and people under 45 years of age are advised to avoid prolonged close contact with you for the first 8 weeks after the implant. You may resume normal activities in a few days without the risk of harmful radiation exposure to those around you. Sexual intercourse may be resumed after 2 weeks and a condom must be used for 2 months. Your sperm may be discoloured for a while and this is usual.

Benefits

An implant will have a good chance of curing localised prostate cancer and this is thought to be equal to the currently used radical treatments of surgery and external beam radiotherapy alone.

The main advantages of this procedure are, short hospital stay, early return to work or activities, fewer complications and avoidance of major radical surgery or prolonged external beam radiation therapy.