When you are diagnosed with prostate cancer, there are many treatment options available including surgery, external beam radiation therapy, brachytherapy (radioactive seed implantation directly into the prostate), hormones, or a combination of these treatments. ARM radiation oncologists specialize in the delivery of radiation and we utilize both external radiation and brachytherapy. In some cases, it is used as a primary treatment. In others, it is used after surgery if there are signs that cancer has recurred. Which technique or set of techniques we use depends on the location and extent of your disease and the specific characteristics of your tumor. Our doctors will work with you and the other members of your treatment team to help you decide which approach, or combination of approaches, is best for you.
External Beam Radiation Therapy
In external radiation therapy, radiation is directed to the prostate from a source called a linear accelerator located outside the body. External radiation therapy is used alone to treat localized tumors, and can be combined with internal radiation therapy (brachytherapy) or other therapies to treat more-aggressive disease. At our cancer centers, we utilize IMRT (intensity modulated radiation therapy) with IGRT (image guided radiation therapy).
IMRT uses modulation of the beam to create ‘beamlets’ and allows for the radiation to be delivered at high doses, while sparing the normal tissue around the prostate (the rectum and the bladder). This technology allows for high cure rates, while decreasing toxicity. IMRT is associated with fewer rectal and bladder complications than other types of radiation. To be able to deliver this treatment accurately, we utilize IGRT – real-time imaging to mold radiation beams to the contours of your tumor. We perform daily CT or ultrasound imaging, to make certain that we account for daily changes in the body and movement. These treatments can be used to treat prostate cancer definitively (42-45 treatments), in cases after surgery where there is a high risk of recurrence, or after a relapse after surgery (37-39 treatments).
Low-Dose-Rate Brachytherapy (Radioactive Seed Implantation)
In low-dose-rate brachytherapy, tiny seeds containing radiation are inserted in or near the tumor while you are under anesthesia. Ultrasound imaging is used to guide the placement of the seeds. In 95 percent of cases, radioactive seed implantation is successful in eliminating the cancer. Low-dose-rate brachytherapy is performed as an outpatient procedure and usually takes a little over an hour. Although the seeds are permanent, they cause little or no discomfort, and their radioactivity diminishes after several weeks or a few months. Patients typically are discharged the day of the procedure and return in one week for follow up, and then 1 month later for CT scans to evaluate how the procedure went.
Which Type of Radiation Therapy Is Right for You?
Which type of radiation treatment our team of radiation oncologists recommends will depend on the aggressiveness of your tumor, how advanced your disease is, and in some cases, your own preferences. The following are some typical approaches for different clinical states.
Radiation Therapy for Localized Prostate Cancer
Localized prostate cancer refers to a tumor that is clearly confined within the prostate. Information from PSA tests, biopsies and imaging tests can indicate whether a localized tumor is in the early stages of development and is slow growing, or is aggressive and growing more quickly.
Radiation therapy options for men with early-stage, localized prostate cancer include:
- Low-dose-rate brachytherapy (radioactive seed implantation)
- Image-guided radiation therapy (IGRT)
For men with locally advanced prostate cancer, options may include:
- Low-dose-rate brachytherapy seeds combined with IGRT +/- hormonal therapy
- IGRT combined with hormone therapy
- High-dose-rate (HDR) brachytherapy
Your ARM radiation oncologist can help you to determine which of these approaches would be best for you.
Often, when a tumor is more advanced or aggressive, men receive hormone therapy before a course of radiation therapy begins and receive it throughout the course of radiation treatments and even afterwards. Some of these men often continue to receive hormone therapy after the course of radiation therapy finishes as well. Hormone therapy reduces the levels of testosterone throughout the body (testosterone stimulates the growth of prostate cancer cells.)
Radiation Therapy following Radical Prostatectomy
Many men undergo radical prostatectomy — surgery to remove the prostate gland — as a primary treatment for prostate cancer. However, sometimes there will be indications several years after surgery that the cancer has recurred. If you experience one of more of these indications — such as a rising PSA level or evidence on a scan — that the cancer is returning after radical prostatectomy, radiation therapy can eliminate or control it.
Your doctor may also recommend radiation therapy if the tumor has not been completely removed by surgery or, if at the time of surgery, the tumor was found to extend outside the prostate gland. Even if your PSA levels are zero, radiation therapy can be important to eliminate cancer cells that escaped the prostate.
IGRT is commonly used following surgery. If a rising PSA and/or a scan indicates that a prostate cancer has recurred locally and has spread to nearby tissues, IGRT can be combined with hormone therapy, which reduces levels of testosterone throughout the body. (Testosterone stimulates the growth of prostate cancer cells.)
Radiation Therapy for Bone Metastases
Because radiation therapy is so focused, it is not often used to treat cancer that has spread from the prostate to other parts of the body. However, the radiation oncology team at Associates in Radiation Medicine has extensive experience using radiation as a treatment for certain prostate tumors that have spread to the bones, where they can cause considerable pain. Radiation can eliminate pain from bone metastases with great success, and this can dramatically improve quality of life for men with advanced prostate cancer.
Radiation Safety
Ensuring your safety during radiation therapy is of the utmost importance at the cancer centers staffed by Associates in Radiation Medicine. Our medical physicists work closely with your radiation oncologist to meticulously plan radiation dosage before your treatment. Medical physicists are also present in the operating room during brachytherapy procedures to ensure that radiation is delivered correctly and in the optimal locations.
Associates in Radiation Medicine has implemented extensive safety protocols to manage our radiation therapy program. Redundancy is built into the review of the computer-based calculations that control radiation dosage, so that multiple experts check them independently. Medical physicists also examine machinery frequently to maintain proper functioning.
Managing Side Effects of Radiation Therapy
Advances in the precision of radiation therapy have lessened the risk of complications. Still, radiation can cause short- and long-term side effects, including incontinence, erectile dysfunction, bowel problems, fatigue, and symptoms in other parts of the body if you receive radiation therapy for metastatic disease. ARM radiation oncologists will work closely with you and your medical team to manage any treatment-related difficulties you may experience.