Radiation therapy damages and kills cells and is used to attack cancer cells. It can be done with external beam radiation therapy or brachytherapy. Prostate cancer cells are generally responsive to radiation therapy. Because of advances in radiation therapy techniques, it has become an effective treatment for locally-advanced prostate cancer. Your doctor may also recommend radiation therapy after radical prostatectomy.
To improve the results of the treatment, your doctor may recommend hormonal therapy together with the radiation therapy. This is known as combination therapy for prostate cancer. A course of hormonal therapy generally lasts 2-3 years.
How is radiation therapy performed?
The goal of radiation therapy is to kill the cancer cells. Because the radiation can also kill cells in other organs, such as the bladder, it is important that the radiation beam mainly targets the cancerous cells and limits the damage to other tissue. Developments in radiation therapy have increased the precision of the beam, and allowed for a higher dosage of radiation with fewer side effects.
The standard course of external radiation therapy (Fig. 1) lasts around 8 weeks, 5 days a week. You receive one dose of radiation per day. The treatment takes about 20 minutes each day, and you do not have to be admitted to the hospital.
Before the start of a course of radiation therapy you will get a CT scan. This is done to map the area that will be radiated as well as the surrounding tissue that should not be treated. In recent years, image-guided radiation therapy has become more widely available. For this type of therapy the radiation oncologist locates the part of the lower urinary tract that should be radiated very precisely with the help of an x-ray or CT scan.
Another form of radiation therapy is brachytherapy. For this type of treatment, a source of radiation is inserted directly into the prostate (Fig. 2).
Brachytherapy alone is not recommended to treat locally-advanced tumours in the prostate. It is generally used in combination with external beam radiation.
|Fig. 1a: External beam radiation therapy damages and kills cancer cells.||Fig. 1b: The radiation beam is directed at the prostate from different angles.|
Fig. 2: In brachytherapy a radiation source (seeds) is inserted directly into the prostate.
How do I prepare for the procedure?
Your doctor will advise you in detail about how to prepare for the procedure. You will receive a schedule for eating and drinking before each session to make sure that your bladder is comfortably full and the rectum is empty before the procedure. If you are taking any medication, discuss it with your doctor. Generally you do not need to stop taking it during radiation therapy.
What are the side effects of the procedure?
Common side effects are a burning sensation when you urinate, urinary frequency, and anal irritation. This is because the surrounding organs, particularly the bladder and the rectum, also receive radiation. Usually these symptoms appear halfway through the treatment course and disappear several months after it ends.
A common side effect of radiation therapy is bleeding in the bladder and the rectum, even several years after treatment. You could also experience lower urinary tract symptoms (LUTS), or erectile dysfunction.
How bothersome the side effects of radiation therapy are, and when they appear, varies from person to person. This is related to your general health and the type of radiation therapy you get.
Read more about how to deal with the side effects of radiation therapy in the section Support for Radiation Therapy.
Treatment after radiation therapy
If during follow-up the PSA level shows that the prostate cancer has not been completely removed you may need additional treatment to remove all tumour cells. Common treatment options are:
- Salvage radical prostatectomy
- Salvage brachytherapy
- Salvage hormonal therapy
What will the follow-up be like?
After radiation therapy for prostate cancer, your doctor will plan regular follow-up visits with you. Routine follow-up lasts at least 5 years. During each visit the doctor will test the level of prostate-specific antigen (PSA) in your blood. In some cases you may need a digital rectal examination (DRE). Follow-up is important to monitor how you recover from the treatment, check your general state of health, and to detect possible recurrence of the cancer.