Types of internal radiation therapy

Internal radiation therapy can be given 2 ways:

• Permanent brachytherapy (seed therapy). With this type of therapy, a long, hollow needle is placed through the skin between the scrotum and anus. The needle is used to put small radioactive metal seeds into the prostate. Each seed is about the size and shape of a grain of rice. The seeds give off radiation to nearby tissues. The seeds stay in place in your body and are not removed. But the radiation gets weaker over weeks and months.

• Temporary (high-dose rate) brachytherapy. With this type of therapy, a long, hollow needle is placed through the skin between the scrotum and anus. The needle is used to put soft nylon tubes into the prostate. The tubes stay in place only during treatment. Over the next day or two, strong radiation sources are put into the tubes for several minutes and are then removed. You need to stay in the hospital for this treatment.

Your treatment plan

Internal radiation therapy may be a choice if your prostate cancer:

• Is growing slowly

• Has not spread outside the prostate gland

A radiation oncologist will create a treatment plan for you. This is a doctor who specializes in treating cancer with radiation therapy. Each person’s treatment plan is different. Your plan will include the type of radiation you will have. It will also include how often and for how long you will have the treatment.

Getting ready for your therapy

Before having internal radiation therapy:

• You may need a lymph node biopsy. This is to see if your cancer has spread outside the prostate gland. One or more lymph nodes are removed to see if they contain cancer.

• You'll have tests to find exactly where to place the seeds. These tests may include a CT scan, ultrasound scan, or an MRI.

During the procedure

Internal radiation therapy is done in a hospital or clinic.

For permanent therapy:

• You may get anesthesia in your spine. This will cause the lower half of your body to be numb. Or you may have general anesthesia. This prevents pain and causes you to sleep through the procedure. 

• Needles are used to place tiny seeds in your prostate.

• You are brought to the recovery room until the anesthesia wears off

• You might be able to go home the same day. Or you may spend a night in the hospital or facility

For temporary (high-dose-rate) therapy:

• You will be given anesthesia during the procedure. This prevents pain.

• Thin tubes (catheters) are placed in your prostate for a few days. Radioactive material is put into the tubes for several minutes at a time. You will stay in the hospital or other facility. After the series of treatments, the catheters are removed.

What happens after internal radiation therapy?

After you finish your therapy, your oncologist and other healthcare providers will closely watch your health. You will have regular lab tests and scans. Make sure you tell your healthcare providers about any symptoms you have. Make sure to go to all of your follow-up appointments.

If you had permanent brachytherapy, the seeds will give off small doses of radiation for at least several weeks. These low doses are not likely to be harmful to others. But to be safe, your doctor may advise you to avoid close contact with pregnant women and small children for a time. Your doctor may also advise other safety measures.

Side effects of internal radiation therapy

Radiation therapy affects normal cells as well as cancer cells. This can cause side effects. The side effects depend on the amount and type of radiation. Some side effects may occur during treatment. Others may occur in the weeks or months after treatment. 

Side effects may include:

• Pain, bruising, or swelling in the area where the needles were inserted

• Feeling tired

• Blood in the urine or semen for a short time after treatment

The bladder and intestines are near the prostate, so these organs can also be affected by the radiation. This can lead to side effects such as:

• Diarrhea or intestinal cramping

• Blood in your stool

• Trouble starting urination

• Feeling the need to urinate often

• Burning feeling when you urinate

These side effects often go away over time, but in some men they might not go away completely. Talk with your healthcare providers about any side effects you have. They may be able to help lessen them.

Erectile dysfunction (ED) after radiation therapy

Another possible side effect is problems with erections. This is known as erectile dysfunction (ED). The risk of this depends on many factors. These factors include a man's age and ability to have erections before treatment. The risk of ED is about the same as most prostate cancer treatments. After radiation therapy, ED tends to develop slowly over time. They can get worse over about 2 years. This is different from surgery, where ED can happen right away but can get better over time.