Radiation therapy can be used as the primary treatment for prostate cancer or in conjunction with other treatments such as surgery or hormone therapy. In early stage prostate cancer, studies have shown that the outcomes of surgery and radiation therapy are comparable.
While there are different forms of radiation therapy, only the highly targetable are used against prostate cancer since it is so important to avoid the bladder and the rectum surrounding the tumor site. One of several highly sophisticated forms of External Beam Radiation Therapy or Internal Radiation Therapy may be recommended, depending on the size and location of the tumor or tumors.
3D-Conformal Radiation Therapy and Intensity-Modulated Radiation Therapy (IMRT)
3D-Conformal Radiation Therapy and Intensity-Modulated Radiation Therapy (IMRT) are two forms of External Beam Radiation Therapy. During 3D-Conformal treatments, a device called a "multi-leaf collimator" will shape the individual radiation beams to “conform” to the shape of your tumor according to the data and instructions it receives from the system computer. IMRT uses thousands of radiation “beamlets” from many different angles to deliver a single dose of radiation. The intensity of the “beamlets” can change during the treatment session to modulate the dose, so that the tumor receives a very precise high dose of radiation, while minimizing damage to surrounding, normal tissue.
Before each session, a Radiation Therapist will carefully position you on the treatment table using a body immobilizer for precise body placement. Image guidance will be used to confirm the location of the tumor before the therapy begins. During your treatment sessions, the radiation delivery system will revolve around you, delivering the radiation according to the plan set by your Radiation Oncologist. Each treatment session lasts from 10 to 30 minutes. Sessions last five to eight weeks. The sessions are pain-free and require no sedation so you can return to your normal activities right away.
The state-of-the-art Calypso System offers sophisticated real time prostate tumor tracking. Subtle movements during treatment can cause the fixed radiation beam aimed at the tumor to touch surrounding healthy tissue. This can lead to incontinence, impotence and other common side effects associated with prostate radiation treatment. Used in combination with external beam radiation therapy, the Calypso system works just like the GPS in a car. It alerts your Radiation Therapist when the tumor is no longer in the treatment target zone and stops the radiation delivery. This avoids irradiating other nearby organs and minimizes unwanted side effects. Since the prostate can be targeted more accurately, the radiation margin can be diminished. This allows your oncologist to prescribe a higher dose of radiation to the prostate and minimize radiation to normal tissue.
Stereotactic Body Radiation Therapy (SBRT)
Stereotactic Body Radiation Therapy (SBRT), another form of External Beam Radiation Therapy, effectively treats cancers in high-risk locations. It is so precisely targetable that Radiation Oncologists can use it to shrink and destroy tumors without damaging vital, nearby tissue. As you undergo therapy, the system’s imaging technology tracks the tumor in real-time and makes adjustments as you breathe, a process called respiratory gating. SRBT provides such precise targeting that Radiation Oncologists can increase the radiation dosage and deliver it over a shorter period of time. You will typically have one to five treatment sessions rather than the standard six to eight weeks of traditional EBRT treatment. During each session, a Radiation Therapist will carefully position you on the treatment table using a full body immobilizer. Image guidance will be used to confirm the location of the tumor before the therapy begins. The sessions are pain-free and require no sedation so you can return to your normal activities right away.
Internal Radiation Therapy (Brachytherapy)
Internal Radiation Therapy, also known as Brachytherapy, targets tumors with radiation delivered through tiny catheters (tubes) that are guided into the prostate using transrectal ultrasound. Low-Dose Rate (LDR) Brachytherapy radioactive seeds, the size of a rice grain, are implanted at the tumor site through the catheters. The seeds remain near the tumor. Over time, the seeds become non-radioactive. With High-Dose Rate (HDR) Brachytherapy, a computer-controlled machine sends the radioactive isotopes through tiny sealed pellets that are inserted down each catheter to deliver the radiation at multiple depths and varying times. The overall treatment time at the tumor site is 10 to 20 minutes. Your treatment plan may require one session or multiple sessions. The catheters are then removed so that no radioactive material remains in the body. You are free to resume normal activity with either treatment.