Radiotherapy, or external beam radiation therapy, for prostate cancer is the term for a particular method of treatment for this disease. High energy beams of radiation are focused on the prostate gland from a source outside your body. Radiotherapy for prostate cancer requires no anesthesia, surgery, or pain and is performed completely on an outpatient basis. Although there remains some debate about its results in the long term, most experts agree prostate cancer radiation therapy is as effective as radical prostatectomy for the first 7 to 10 years after treatment.
The intent of radiation treatment for prostate cancer is to kill the cancerous cells, thus controlling their growth and preventing them from spreading further. Experts continue to debate whether the radiation actually kills the malignant cells or only stuns them, because recent studies show prostate cancer can still be present but inactive or dormant, even after years of treatment.
The presence of cancer should not be a concern as long as it remains inactive, which is why your physician will emphasize the importance of monitoring your prostate-specific antigen (PSA) levels after undergoing prostate cancer radiation therapy. The cancer may start to grow slowly after radiation but never become a problem for you during the rest of your life. Nevertheless, if your PSA levels starts to rise, it suggests that the cancer is growing and to consult with your doctor to see if there is any reason for concern.
The Types of Radiotherapy for Prostate Cancer
In the past ten years, radiation treatment for prostate cancer has evolved from using conventional x-rays to more advanced methods of designing and delivering a patient’s radiation treatment. Prostate cancer radiation therapy now uses advanced technology that is able to precisely aim the radiation beams and cause less trauma to the normal tissues.
The current methods of radiotherapy for prostate cancer are:
- Three dimensional conformal therapy (3DCRT), which uses specialized computers to map the precise location of your prostate to administer radiation. Three-dimensional imagery of your prostate, bladder and rectum are created so that your radiation therapist can shape the radiation beam to conform to your prostate gland, lessening the radiation on the surrounding normal tissues.
- Intensity-modulated radiation therapy for prostate cancer (IMRT), which is a more advanced technology of three-dimensional therapy. Aiming radiation beams from several directions, your radiation therapist deliver a high dose of radiation to the cancer while reducing any complications. The strength of the radiation beams is adjusted to minimize the dose of radiation reaching the most sensitive normal tissues.
- Conformed proton beam radiation therapy for prostate cancer, which is the latest technology related to the 3DCRT and is similar in approach. Instead of using x-rays, beams of positively charged subatomic particles, or protons, are focused on the cancer. The protons destroy the malignant cells in a method similar to x-ray but seem to have less damage to normal tissues they pass through and may lead to fewer side effects. Studies have shown that the outcomes after proton beam therapy are similar to the outcomes after using x-ray therapy.
Good Candidates for Radiotherapy for Prostate Cancer
The men with certain characteristics are ideal candidates for radiotherapy. For prostate cancer patients with low risk or early state prostate cancer, external beam radiation therapy is an appropriate option as a primary treatment. Your doctor may have suggested radiation treatment for you prostate cancer if you have:
- T2 stage disease
- Gleason score of 6 or lower
- PSA level under 10
- Without any extensive abdominal scar tissue from other surgeries
- Cancer still restricted to the prostate gland
Even if you do not meet the criteria, this does not necessarily preclude you from using radiation treatment for your prostate cancer. If you have an increased risk of advanced cancer, your doctor may suggest to combine hormone therapy and external beam radiation therapy for your prostate cancer. Discuss your options with a qualified radiation oncologist to see if radiotherapy is right for you.
What is Involved in Radiotherapy for Prostate Cancer
Before starting radiation treatment on prostate cancer, imaging from MRIs, X-rays and CT scans help doctors determine the exact location of your prostate gland and the appropriate dosage of radiation. Because they need images of your prostate, bladder, rectum and any other critical structures within the pelvis, you may be required to take an enema the evening before the procedure to empty your bowels and maintain a partially-filled bladder just before the procedure.
Your radiation team will then mark areas on your skin with ink. Later, they will use these inked marks as a guide to focus the radiation. Patients undergoing this treatment are fitted with a plastic mold resembling a pelvic cast to minimize movements during actual treatments. The entire process can take 1 to 2 hours. Usually, in about 5 to 10 days, your team will ask you to come back for additional fine-tuning before having you begin the actual radiation treatment on prostate cancer.
When it is administered in standard daily doses, usually external beam radiation therapy on the prostate cancer will usually occur over a period of about 7 weeks, and sometimes up to 9 weeks. An ultra sound image may be taken of your pelvis each day to make sure your prostate is in the proper position for treatment. The radiation treatment itself is painless, and each session will occur Monday through Friday, lasting about 10 to 15 minutes. This schedule of radiation treatments allows your body’s normal cells to recover over the weekend, and over time, this will help destroy or disable the prostate cancer cells more efficiently.
Because of the characteristics of cancer cells, including the rate of their growth and ability to heal, the schedule of radiation treatment for prostate cancer should not be shortened. Sometimes, doctors can reduce the treatments to 3 days a week. While it sounds more convenient, especially for men with busy schedules, reducing the amount of treatment means increasing the amount of radiation dosage. It is also less effective and increases your chances for side effects and complications.
After undergoing radiotherapy for prostate cancer, patients will need to return to their doctor every 3-6 months to check their PSA level and evaluate any remaining side effects from the treatment.
Advantages and Disadvantages Radiotherapy for Prostate Cancer
|
Advantages |
Disadvantages |
|
|
It takes time for the cumulative effects of radiation to manifest, so for the first few days, and sometimes up to two weeks, of prostate cancer radiation therapy, most men are able to continue with their normal activities, such as working, driving, exercising, and having sex. By the third week, most men experience mild to severe side effects of radiation treatment for the rest of their treatment schedule. The more obvious side effects from prostate cancer radiation therapy is pubic hair loss and marked fatigue, which begins about half way through the course of the radiation treatment.
Side Effects of Radiotherapy for Prostate Cancer
- Pubic Hair Loss
- Fatigue
- Changes in Urination
- Bladder or Rectal Irritation
- Bleeding in the rectum or bladder
- Erectile dysfunction
Although its long-term efficacy is still being determined, all forms of radiotherapy or external beam radiation for prostate cancer remains a mainstay of treatment for men with localized prostate cancer. Whether or not the prostate cancer radiation therapy kills or stuns the cancerous cells is still up for debate, but it can mean the next 7 to 10 years without the symptoms or signs of prostate cancer. You should discuss with your doctor the potential risks and side effects, as well as the benefits of radiotherapy for prostate cancer.
