What Happens During Internal Radiation Therapy (Brachytherapy) for Prostate Cancer
For this type of radiation, your doctor uses a needle to place tiny radioactive pellets into your prostate. These pellets are also called seeds. The seeds can be temporary or permanent. They're so small that you won't feel them.
Two types of permanent radioactive seeds can be used. They are palladium 103 and iodine 125. Palladium is usually used to treat more aggressive cancers. The procedure requires only one treatment. These seeds give off small doses of radiation for several weeks. They stay in place after their radioactivity is used up.
Temporary brachytherapy usually uses iridium 192 or cesium 137. Small, hollow tubes called catheters are placed into the prostate and left in place for several days. The radioactive material is put into the catheters for several minutes at a time, usually for about three treatments. When this type of radiation is used, it is usually along with external radiation.
Preparing for internal radiation
Before having internal radiation, you may need to have a lymph node biopsy to see if your cancer has spread outside the prostate. You may be able to have the biopsy done laparoscopically. That means you'll have a small incision and the nodes are removed with a special tool called a laparoscope. Or you may need a larger incision under your belly button to remove them.
To prepare for seed placement, you'll have an appointment to have some imaging tests. These tests may include a CT or MRI scan and transurethral ultrasound. They help your doctor see inside your prostate. That way, he or she can map out exactly where the seeds need to be placed.
The day before the procedure, your doctor may ask you not to eat anything and to drink only clear liquids. The night before your procedure, you may also need to have an enema to clean out stool from your rectum.
What happens on the day of the procedure (permanent brachytherapy)
On the day of the procedure, you may have a local anesthetic to numb the area between the scrotum and anus, called the perineum. Or you may have a general anesthesia to be put to sleep. While you lie on your back, your surgeon will put a tube, called a catheter, into your penis. The tube allows your doctor to place a tiny bit of radioactive dye to help see your bladder on a special type of X-ray called a fluoroscopy. This helps your doctor know where your prostate is. Your doctor also uses an ultrasound probe placed inside the rectum during the procedure to see the prostate area.
Once he or she has a clear view of your prostate, your surgeon carefully guides needles through the perineum to inject the seeds. The doctor then removes the catheter and checks the X-rays to see if the seeds are in the right place. Your doctor also uses a small scope, called a cystoscope, to look into your urethra and up to the bladder. This is to check that no seeds went into your bladder or urethra.