What Is Radiation Therapy?
Answers to the most frequent questions about different types of radiation therapy
Radiation therapy uses high-energy beams to kill cancer cells. There are several forms of radiation that can be administered non-invasively from outside of the body, similar to an X-ray, and other forms that are administered internally through implants. Radiation therapy is a very common type of treatment for many types of cancer.
Here are some of the most frequently asked questions about chemotherapy. Rocky Mountain Cancer Centers provides the most advanced cancer treatments available to thousands of patients every year throughout Colorado.
Continue reading below for a comprehensive guide to radiation therapy or jump directly to the section that interests you most by clicking on one of these questions:
- What is radiation therapy?
- How does radiation therapy work?
- What are the different types of radiation therapy?
- How does my doctor determine if radiation therapy is right for me?
- Why should I choose Rocky Mountain Cancer Centers for my radiation therapy?
- How do I become a patient at Rocky Mountain Cancer Centers?
- Will I have other treatments in addition to radiation therapy?
- Who will oversee my radiation therapy?
- When will I start getting radiation therapy?
- How often will I need radiation therapy? And how many radiation treatments will I need?
- What will happen at my first radiation therapy appointment?
- How is radiation therapy administered, and what should I expect during radiation treatments?
- What are the side effects of radiation therapy? What can I do to help with side effects of radiation therapy?
Radiation therapy uses high-energy X-rays, gamma rays, electron beams, or protons to kill or damage abnormal cancer cells and shrink cancer tumors. Radiation therapy is sometimes called
radiotherapy, irradiation or X-ray therapy.
Radiation therapy that uses high-energy X-ray is not the same as an X-ray to determine if you have a broken bone. If you’ve ever had an X-ray such as that, you’ve been exposed to a low dose of radiation. Radiation therapy used to treat cancer uses a much higher dose of radiation aimed specifically at the area of the body where the cancer is located.
Radiation therapy has been used since the early 1900s to treat cancer. In some cases, radiation therapy is used alone to kill cancer cells. However, radiation therapy is most commonly used along with surgery and/or chemotherapy.
The decision to include radiation therapy in your treatment plan was made based on many unique factors, including the size and type of your tumor, genetic, health history, and personal health goals. At Rocky Mountain Cancer Centers, all treatment plans — including those that include various types of radiation therapy — are created based on proven medical research and national standards of care.
During radiation therapy, cancer doctors who specialize in this form of treatment — called radiation oncologists — will plan and oversee your radiation therapy treatment. During each radiation therapy session, your radiation oncologist or a radiation therapist will expose the cancer cells to high-energy radiation using specialized external equipment or by implanting radioactive material at the site of the cancer. The exposure causes the DNA in cancer cells to fracture. Once the DNA is fractured, the cells have a difficult time growing. The cells will either continue to grow very slowly or they will stop growing completely and die off.
Surrounding healthy cells will be exposed to some radiation, too, but most of them will recover and continue to function properly whereas cancer cells will not. Rocky Mountain Cancer Centers uses the most advanced and latest radiation technology that helps minimize the exposure or effect on healthy cells. Every piece of technology used at Rocky Mountain Cancer Centers is accredited and checked daily to ensure the highest level of pinpoint accuracy.
There are two main types of radiation therapy: external beam radiation therapy and internal radiation therapy.
External beam radiation therapy is delivered via a machine from outside the body using a beam directed at the site of the cancer. The equipment does not make physical contact with the body and it can be moved around the body to deliver radiation beams from different angles. Treatment is typically administered five days a week for a period of one to 10 weeks.
External beam radiation therapy technology used at Rocky Mountain Cancer Centers includes:
- Image-guided radiation therapy (IGRT), which uses imaging such as computed tomography (CT), ultrasound, or X-rays to consistently and accurately direct external radiation dose.
- Intensity-modulated radiation therapy (IMRT), a type of external beam radiation that uses multiple beams to precisely shape the high doses of radiation around the tumor and attempt to avoid giving high doses to surrounding critical organs that can’t tolerate these high doses.
- Stereotactic radiosurgery (SRS) uses advanced Novalix Tx linear accelerators that perform similar to Cyberknife and Gamma Knife, but allow treatment of larger more irregularly shaped tumors. It was designed specifically to treat brain tumors.
- Stereotactic Body Radiation Therapy (SBRT) uses a technique similar to stereotactic radiosurgery (SRS) to treat tumors outside the skull, like lung and liver.
Internal radiation therapy involves implanting radioactive material in the body near or inside the tumor. Different types of brachytherapy implants include pellets, seeds, ribbons, wires, needles, capsules, balloons, or tubes. The implant is placed using catheters, small tubes inserted through veins or arteries without surgery. Depending on the type of material used, it may be left in for a few minutes, a few days, or permanently.
At Rocky Mountain Cancer Centers, we offer two forms of internal radiation therapy:
- High-dose rate, or HDR, brachytherapy is frequently used in the treatment of uterine or cervical cancers and is now being used for some forms of skin cancer. When using HDR brachytherapy, our board-certified radiation oncologists place the radioactive material inside the body for just a few minutes at a time. The radioactive material is removed before the patient goes home. Treatment is usually repeated three to five times with about a week between each session.
- Selective internal radiation therapy (SIRT) is an image-guided, non-surgical procedure used to treat tumors in the liver. Our board-certified radiation oncologists work alongside an interventional radiologist to deliver tiny radioactive beads into the blood vessels that lead directly to the tumor. The radioactive material destroys the blood vessels leading to the tumor, which reduces or stops growth of most liver tumors.
For details on how these various radiation therapy treatments work and to learn where each is offered within Rocky Mountain Cancer Centers, please go here .
When you received your cancer diagnosis, you most likely were referred next to a cancer surgeon or a cancer specialist called a medical oncologist. At that point, a treatment plan including radiation therapy was developed was based on many factors, including:
- Type and grade of cancer
- Size and location of the tumor
- Sensitivity of surrounding tissue
- Genetic components
- Family history
- Your age, overall health and medical history
- Your treatment goals and preferences
Another factor that may affect your radiation therapy treatment plan is whether you have received radiation to that body part in the past. Each area of the body has a safe lifetime dose of radiation it can receive. The decision to use radiation for recurrence will depend on the location of your tumor, the type of cancer, and the amount of radiation previously used.
Radiation therapy may be recommended alone or it may be recommended before, during, or after other treatments, such as surgery, chemotherapy, or immunotherapy. Once you have been referred for radiation therapy, either from within Rocky Mountain Cancer Centers or from a community provider, we usually can schedule you for your first appointment within two days.
Radiation therapy is a specialty that requires a high level of skill, precision, and experience. You also want to make sure your provider utilizes state-of-the-art technology and has strict protocols in place to ensure on an ongoing basis that all equipment is properly functioning and precisely calibrated daily so that the high-energy radiation is delivered with pinpoint accuracy.
At Rocky Mountain Cancer Centers, we have been delivering the highest quality of radiation therapy treatment to patients throughout Colorado for more than 20 years. All of our radiation oncologists are board-certified, which means that you will be treated by highly trained and experienced physicians — not doctors who have just completed their training or who are still in residency. In addition, our entire radiation therapy staff from dosimetrists and radiation technicians to nurses and financial counselors work only in radiation therapy and all hold certifications where available.
Other factors to consider include:
- Technology: Radiation therapy relies heavily on equipment, so be sure to select a center with the most advanced technology.
- Experience: When it comes to choosing a provider, experience counts. At Rocky Mountain Cancer Centers, we have been treating patients since 1992.
- Timeliness: Once referred, we try to accommodate all new patients in for their first visit within 24 to 48 hours.
- Affordability: Rocky Mountain Cancer Centers is the largest community-based cancer network with clinics throughout Colorado. This allows us to offer our services more cost-effectively. Learn more about the importance of a community-based cancer network.
- Insurance: Be sure to check that the facility accepts your insurance and specific plan. Rocky Mountain Cancer Centers provides Patient Financial Counselors who specialize in radiation therapy to work one-on-one with you to understand what your insurance plan will cover, what you will be responsible to pay, and what financial aid is available.
- Innovation: While most changes in radiation therapy occur through the technology, researchers are always exploring techniques to better deliver radiation therapy. As part of the US Oncology Research network, the clinical teams at Rocky Mountain Cancer Centers stay up to date on the latest developments, ensuring that you will receive the best care supported by medical evidence.
Thousands of patients from throughout Colorado are treated at Rocky Mountain Cancer Centers each year. We stay current on the latest treatments supported by medical evidence and ensure our patients get the best care possible. Patients come to our centers from many different avenues, including:
- Referrals from community physicians: Most of our patients are referred for treatment to us by either their primary care doctor, the doctor who made the diagnosis, or a surgeon. We are honored to be trusted by so many physicians in our communities and we work hard to communicate with them about each of their patients and ensure they have complete information for when patients return to them after cancer treatment.
- Second opinions: Patients may feel more comfortable or confident with the treatment plan that is recommended for them if an independent physician reviews their case. In some instances, insurance plans may request or require a second opinion. Rocky Mountain Cancer Centers is happy to provide second opinions.
- Self-Referral: Patients may seek care at Rocky Mountain Cancer Centers on their own for many reasons, including reputation, access to clinical trials, or convenience. We welcome these patients and will work closely with their prior physicians to obtain medical records and maintain continuity of care.
In some cases, radiation therapy will be the only treatment needed to treat a cancer, but often it is used in conjunction with other treatments, such as surgery, chemotherapy, immunotherapy, or some combination.
- Radiation therapy used as preoperative therapy to shrink a tumor that will then be removed surgically is referred to as neoadjuvant therapy.
- When radiation is administered at the same time as chemotherapy or immunotherapy, it’s called concurrent treatment.
- Radiation therapy used as a treatment after surgery or chemotherapy is called adjuvant therapy. Its goal is to kill off any cancer cells that may have been left behind to reduce the chances of recurrence.
A doctor who specializes in using radiation to treat cancer — called a radiation oncologist — will oversee your radiation therapy. If you are having more than one type of treatment, your radiation oncologist will work closely with the rest of your cancer team to coordinate your care. Your radiation oncologist also communicates with your primary physician about your treatment plan, your progress, and any follow-up care that may be needed.
In addition to your radiation oncologist, other team members involved in administering your radiation therapy include:
- Radiation physicist: Calibrates radiation equipment and ensures it delivers the proper amount of radiation as prescribed by your radiation oncologist.
- Dosimetrist: Uses computer imaging to create a radiation delivery plan based on the location of the tumor.
- Radiation therapist: Positions you for treatment and operates radiation equipment.
- Radiation therapy nurse: Educates you on radiation therapy, assesses your response to treatment and helps you manage any side effects that you experience.
When your treatment plan is developed, it will outline whether you will be receiving radiation therapy before, during, or after other treatments. Once you are ready to begin radiation therapy, you can usually be seen within one to two days at Rocky Mountain Cancers Centers.
Rocky Mountain Cancer Centers specializes in providing expert cancer treatment once patients are diagnosed, so our patients come from many different health systems and physicians. We pride ourselves on working with any referring physician to ensure your care is coordinated.
Radiation therapy treatment schedules vary widely based on:
- Type and location of cancer
- The goal of your treatment: whether it is to rid your body of cancer, slow the cancer’s growth and progression, or ease the symptoms of your cancer
- Type of radiation therapy used
Most external beam radiation, when used to shrink a tumor before surgery, is administered five days a week for five to eight weeks. Fewer treatments may be used if the goal is easing cancer-related symptoms.
Internal radiation (brachytherapy) is typically administered over the course of a few weeks with at least a week in between each treatment.
Your first radiation therapy appointment at Rocky Mountain Cancer Centers won’t include any actual radiation therapy. Instead, you’ll come in for a CT scan, which is used to plan your radiation therapy (called CT simulation). You also will have tiny permanent marks (sometimes referred to as “tattoos” although they look more like a freckle) that will guide the targeting of the radiation therapy during treatment. This appointment takes about 30 minutes.
After you leave, your radiation oncologist will use your scans to map out the exact location of the cancer within your body as well as noting the location of any surrounding healthy organs that need to be avoided during treatment. Computer modeling is then used to simulate the dose of radiation that will be delivered to the tumor during treatment, and the model is reviewed before your treatment begins. This process can take up to two weeks before you return for your first actual radiation therapy treatment.
What happens during your radiation treatment sessions depends on what type of therapy you are receiving and where in your body the cancer is.
External beam radiation treatments:
• Typically administered every weekday for five to eight weeks
• Last between 15 and 30 minutes
• Are noninvasive and painless.
Internal radiation treatments:
• Typically completed in one session or a series of three to five sessions about a week apart
• Involve inserting a catheter at the site of the tumor to deliver radioactive material
• Are typically administered with a local anesthesia.
Radiation therapy side effects are caused by healthy cells or organs being exposed to radiation in addition to the cancer cells. At Rocky Mountain Cancer Centers, we use the most advanced, state-of-the-art radiation therapy machines, including image-guided radiation therapy (IGRT), that help reduce any exposure to non-cancerous cells, organs, and tissue. In addition, we employ various techniques proven through research to help reduce exposure, such as having you breathe in specific ways or lie in certain positions to move organs away from the radiation site.
As with any medical treatment, radiation side effects vary from patient to patient with some experiencing highly unpleasant symptoms and others barely having any at all.
Fatigue and skin reactions are the most common radiation side effects. Others depend on the area of the body being treated. For instance, unless you are receiving radiation therapy to your head, you probably won’t lose your hair.
If you are a patient and are experiencing worsening symptoms from your treatment, such as those listed below, our medical professionals are available 24 hours a day, 7 days a week to help. We can assess signs and symptoms, schedule you for an in-office, same or next day appointment and help you avoid a trip to the Urgent Care, ER or unplanned hospitalization. In the event of a life-threatening emergency always call 911. Call us if you are experiencing:
- Chills or fever greater than 100.4
- Burning with urination , frequency, urgency, lower back pain (UTI)
- Productive cough with green, yellow, red, brown sputum
- Unmanaged diarrhea, constipation, nausea, vomiting
- Unmanaged pain
- Swelling, redness and pain on extremities
- Shortness of breath/chest pain
- Dizziness with changing position or lightheadedness
- Dark urine, less urine than normal, thirst, dry mouth (dehydration)
- Mouth sores, difficulty swallowing, frequent or sever heartburn
- Severe fatigue