What to Expect During Treatment
Fighting cancer is challenging. To help you prepare for the fight, here is a brief outline of what you can expect during external beam radiation therapy or radiosurgery. The details of some of the steps may differ depending on your particular case.
A Team Approach
Radiation treatment is administered to you by a team of highly qualified health care professionals. This team is comprised of specialists that among them have years of experience in treating cancer. Some of the typical members of the team are listed below; depending on your particular case, other specialists may be asked to join the team.
The radiation oncologist is your doctor through this process—A medical doctor who specializes in the use of radiation for treating cancer. The radiation oncologist will prescribe, plan and direct your treatment and is responsible for deciding what method of radiation is indicated for your case.
The medical physicist works with the dosimetrist and the radiation oncologist to measure the precision of your treatment plan, and works with the equipment to calculate the best angles to treat your tumor, or tumor site. They also run frequent safety checks and make sure that the equipment is working properly.
The dosimetrist works closely with the radiation oncologist and the medical physicist in designing your treatment. The dosimetrist determines the best angles from which to deliver the radiation, prescribes the length of time for each pulse of radiation, and develops strategies on how best to avoid giving radiation to healthy tissue in your body.
The radiation therapist will conduct your treatment each time. He or she will position you on the treatment table so that radiation can be delivered, run the equipment, and works very closely with the medical physicist during your treatment.
The radiation nurse coordinates your care, helps you learn about treatment and about managing any potential side effects that you might experience.
If your oncologist recommends radiation therapy, the first thing you will do is meet with a radiation oncologist. Based on your specific case, your radiation oncologist will tell you what type of radiation therapy he or she recommends, whether it will be given alone or in conjunction with other treatment methods, what the specific goals of treatment are, and what side effects you may expect. You can talk to your doctors about your treatment options and make a decision together.
The consultation is an excellent opportunity for you to ask the doctor whatever questions you may have. Click here for a list of some common questions you could ask.
Next, you will come in for simulation. Detailed images will be taken of the treatment area to show the location of your tumor and the normal areas around it. These scans usually include a CT scan, but they can also include MRI, PET, and ultrasound scans. The scans are analyzed and combined by a sophisticated software program to create a detailed 3-D image of your tumor site and surrounding tissues. Your doctor can rotate the image on his computer screen in order to view the tumor from every angle. If you are interested in seeing the images, ask your doctor to show them to you.
During the simulation, your radiation therapist will help you find the most comfortable position on the treatment couch. He or she will also help you get into that same position for each treatment session that follows. Temporary skin marks and even tiny tattoos (about the size of a freckle) are used to help guide you into position each day for treatment. Your radiation therapist will work with you to find a pose that feels right for you and can meet the treatment goals.
For lung cancer, radiation oncologists may use respiratory gating technology. For this treatment technique, your team studies the motion of your chest as you breathe. In some cases, a special CT image (called Cone Beam CT or CBCT) will be taken by the machine just after you have been positioned on the treatment table. This involves rotating the gantry around you while images are taken. This enables the doctor to see if the position of the target has shifted at all. If it has, you will be repositioned based on this new information.
A small device called a chest block is used while the CBCT is being taken. Very simply, the chest block tells the doctor if you are breathing the same way as you were earlier, and the CBCT tells the doctor if your internal organs are moving the same way as they were in previous sessions. Because of the way the machine works, both pieces of information need to be captured at the same time in order to achieve the accuracy required for effective treatment.
After simulation is completed, the radiation oncologist will meet with the radiation physicist and dosimetrist to design the details of your treatment plan. No two patients and no two targets are exactly alike. That's why your doctor will develop a treatment plan that's been carefully customized for you. After taking into account the location, type, and stage of your cancer, your medical history, lab tests, and other factors, your treatment team will use sophisticated computer software to assist them in prescribing the exact volume to be treated, the total amount of radiation that will be delivered to the tumor, the angles for the radiation beams, how many treatments you will have.
Before each day's treatment, you may be asked to change into a gown. Then the radiation therapist (RT) will help you lie down on the treatment couch. The couch will be adjusted so a laser light shines on the mark that was put on your skin, helping to position you correctly. Next, the two arms of the machine's On-Board Imager (OBI) will extend on either side of you in order to create an image of the tumor in that day's treatment position and match it to the position that was planned for you. The scan is compared to the planned position, and if there is any difference between the two, the RT can, with the touch of a button, adjust the couch to align you perfectly for treatment.
Your RT may offer to play soft music while you are in treatment. You can also ask your team about other ways to help make you more comfortable.
If you are treated on a Varian machine, it will have a gantry, which is the head of the machine. The gantry houses a device called a multi-leaf collimator that "shapes" the radiation beam so it conforms to the shape of the tumor from any given angle. During your treatment, the gantry will move around you to deliver the radiation with sub-millimeter accuracy. The radiation beam is not visible to the eye when it leaves the gantry so you will not see it. Depending on the type of treatment, the time that the radiation beam is on will vary from a few minutes to 15-20 minutes. For VMAT, the radiation beam will likely only be on a few minutes, while for radiosurgery or SBRT, the machine will most likely be closer to twenty minutes or longer.
You may experience some side effects from radiotherapy or radiosurgery. If you do, they might not begin until after several sessions because the effects of radiation treatment are cumulative. Two of the most common side effects are irritation or damage to the skin near the treatment site, and fatigue. Talk to your doctor before and during treatment if you have any questions or experience discomfort. Click here to see more about possible side effects you may experience.
After your treatment has ended, your doctor will recommend a schedule for periodic checkups to monitor the results. Typically, checkups are scheduled at six-month intervals. If symptoms or clinical circumstances suggest a recurrence, diagnostic tests such as blood tests, ultrasound, CT scans, MRIs, chest x-ray (CXR), or a bone scan may be needed.
