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 (EBRT). 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.