Services and Procedures
The goal of modern radiation oncology is to precisely target the tumor while sparing nearby organs and structures, what sometimes is called "conformal radiation therapy." Depending on clinical situation, different degrees of conformity and different conformal techniques may be used.
Our patients typically go through the following steps:
1. Consultation: You'll meet with a radiation oncologist for a discussion of your cancer, and together you'll decide whether or not radiation would be appropriate in your case. If we decide to proceed with treatment, we'll describe exactly what the treatment will involve.
2. Simulation: This is a mapping procedure that will allow your physicians, and the physicists they work with, to plan out how exactly your radiation treatment will be delivered. The simulation often consists of a special type of CT scan. Sometimes, intravenous contrast is used. Special positioning devices often are used to help you lie in a particular position. Our goal is to make the procedure as comfortable for you as possible.
3. Radiation planning: After the simulation, your physicians and physicists will work together to devise the best possible radiation plan. The aim is to deliver the radiation exactly where it's needed and to avoid the areas where it could cause the most side effects.
4. Radiation delivery: Radiation treatments often are given daily, Monday through Friday, for a number of weeks. The treatments are usually painless, and patients generally tell us that they don't feel a thing. During your treatment course, you will meet regularly with your physicians to address any side effects you're experiencing and to answer any questions you might have about your treatment.
UI Health has a number of advanced technologies to use with patients receiving radiation, including stereotactic radiosurgery, stereotactic body radiotherapy, brachytherapy, and image-guided radiotherapy. Your radiation oncologist can explain these and other treatments to you, and help you decide when they might be useful to you.
Three-Dimensional Conformal Radiation Therapy (3D-CRT)
Three-dimensional CRT uses a special CT scanner to precisely map the location of your tumor. Using a computer program, we can plan radiation beams from multiple directions that will target your cancer without affecting nearby organs.
Intensity-Modulated Radiation Therapy (IMRT)
This is an advanced form of external beam radiation therapy. A special CT scanner is used to precisely map the tumor in three dimensions. Specially trained physicists then use a computer program to design a sophisticated radiation plan wherein the radiation dose going to each portion of the tumor is precisely controlled. The linear accelerator that delivers the radiation is computer-driven, and it moves around the patient as it delivers the treatment. IMRT allows for tight regulation of where the radiation dose is distributed in the patient's body. In this therapy, the radiation dose going to sensitive organs and structures, even if they're right next to the tumor, can be kept to a minimum.
A variation of IMRT called Volumetric Arc Therapy (VMAT), or RapidArc®, allows the delivery of a radiation treatment quickly as the linear accelerator rotates once around the patient's body.
Stereotactic Radiosurgery (SRS)
Stereotactic treatments use multiple highly focused beams of radiation directed at a tumor with the goal of giving a high dose of radiation to the tumor, while only low radiation doses go to nearby organs and tissues. The term stereotactic radiosurgery (SRS) is used for targets inside the skull, while stereotactic body radiotherapy (SBRT) is used to describe the approach for targets outside the head.
Though the treatment does have the word "surgery" in its name, no knife or scalpel is used. One critical element of both SRS and SBRT is that the target tumor is held as still as possible during the treatment. Sometimes this necessitates placement of a halo-like metal frame on the patient's head before treatment (sometimes called frame-based radiosurgery); other times, it is done without the frame (called frameless radiosurgery).
Total Body Irradiation (TBI)
Total body irradiation refers to when a person's entire body is treated with radiation. This is a technique sometimes used for patients with lymphomas or leukemias, often in combination with high-dose chemotherapy and a stem cell transplant.
Instead of using radiation beams aimed toward a tumor from outside the body, during brachytherapy a radiation source is placed close to or inside the tumor. Depending on the patient's clinical situation, the source may be left in the body for only a short time, called high-dose rate (HDR), or it may be left there for a long period of time, called low-dose rate (LDR). Using brachytherapy allows the doctor to administer a higher dose of radiation to the tumor than usually is possible with external radiation treatment, while also giving very little radiation to surrounding organs and tissues.
Ophthalmic plaques are a type of brachytherapy treatment. Historically, any patient with a choroidal melanoma — a type of tumor that forms on the back of the eye — had to undergo surgical removal of the eye itself. Fortunately, today there is an alternative. Working closely with our colleagues in Ophthalmology, we design and build a slightly cupped radioactive disc, called a plaque, which is sewn in place over the back of the affected eye, overlying the tumor. The plaque is left in place for a number of days, then removed. This allows a high dose of radiation to be given to the tumor, with very little going elsewhere. This means that patients can often keep their eye and have relatively little decrease in their vision.
Image-guided radiation therapy (IGRT) is a description of a radiation technique wherein the position of the target is checked — often with a special CT scan or a set of X-rays — immediately before or even during each treatment. It is an option on some newer radiation machines that have imaging scanners built into them. This advance lets the doctor take pictures of the tumor and make minor aiming adjustments just before giving the radiation. This allows extremely precise delivery of radiation treatments. Though it is not indicated for every clinical situation, we are fortunate to be able to offer it in our department.
One version of IGRT, called Calypso, can be used for prostate cancer patients. For those patients, tiny beacons — each one roughly the size and shape of a grain of rice — are implanted into the prostate gland before the radiation course begins. A special antenna is used during each radiation treatment to allow for precise, real-time monitoring of movement of the prostate. This precision means that the radiation oncologists and physicists who design the radiation plan can use extremely tight margins, reducing the radiation dose that goes to nearby organs and structures.
Our expert radiation oncologists would be happy to talk to you about these treatments or other techniques that might be useful in your case. To request an appointment, please call 312.996.3631.