Radiation Therapy: What to Expect

More than half of all people with cancer will require radiation therapy at some point during the course of treatment. This may be used to destroy or shrink tumors, sometimes before or after cancer surgery, and to help alleviate symptoms.

If you or a loved one are navigating a cancer diagnosis, you may be wondering what to expect. Read on to learn more about radiation therapy and prepare for every step of the care process.

Radiation therapy, or radiotherapy, uses ionizing radiation produced by a linear accelerator (LINAC) to destroy cancer cells and shrink tumors. The radiation passes through the body and delivers dose to the affected area while minimizing dose to the skin and tissue it passes through.

Although the radiation affects both cancerous and normal cells, it has a greater effect on the cancer cells, damaging their genetic material and making it impossible for these cells to continue to grow and divide. Treatment aimed to cure will give the highest possible dose of radiation to the cancerous area (within safe limits) to attempt to destroy all the cancer cells. Sometimes smaller doses are used, with a goal to reduce the size of a tumor and/or relieve symptoms.

Most patients undergo radiation therapy once a day, five days per week, over a period lasting from two to 10 weeks. The total time, beginning with your first and ending with your last session, is called a course of treatment. Some patients are prescribed hypofractionated radiation therapy, which delivers higher doses of radiation in a more targeted fashion over fewer treatments.

Electrons are used to treat skin cancers and other superficial lesions as they are absorbed by the first few centimeters of skin, leaving very little dose to pass into the body. Radiation therapy is used to both cure disease and alleviate the symptoms of cancer. There are also a number of non-malignant conditions that are treated using radiation therapy.

Radiation therapy is typically administered using high-energy X-rays or other types of radiation to target and destroy cancer cells. The delivery involved several steps, starting with treatment planning. Once the treatment plan is finalized, patients receive their therapy in a controlled environment, often in specially designed treatment rooms. Radiation therapy machines, such as linear accelerators, generate and direct the radiation beams precisely at the tumor while minimixing exposure to adjacent healthy tissues. 

Treatment sessions are typically short and painless, lasting only a few minutes, and patients usually receive multiple sessions over a specified period to maximize the therapy’s effectiveness while minimizing side effects. The entire process is closely monitored by a team of radiation oncologists and therapists to ensure the accurate delivery of radiation to the targeted area, ultimately aiming to eradicate cancer cells or shrink tumors.

Here’s what a typical appointment for radiation therapy looks like:

The radiation oncologist may ask for diagnostic procedures to be undertaken, either in the radiation therapy department or at a general hospital. These can include X-rays, computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET) scans, biopsies and blood tests. Once the nature of the disease has been established, a treatment regime will be planned and prescribed.

MRI, CT or PET scanning, or ultrasound is required to determine the exact size, shape and position of the area to be treated within the body, known as the treatment site. These images are then used to plan the patient’s treatment. You are positioned exactly as you will be for your treatments, which may involve the use of immobilization devices to help you keep still. Marks are made on your skin to indicate the treatment area. Once you are positioned, images are acquired to help your treatment team plan as precise a treatment as possible while reducing the impact on organs and critical structures.

Once your images have been taken, your physician prescribes the appropriate total dose of radiation and the number of days your treatment is to be administered, considering the tumor target and critical structures in the treatment area. Your physicist and dosimetrist work closely with your radiation oncologist and use sophisticated software to calculate the position, dose and frequency of the series of radiation beams that are to be your treatment. Before treatment commences, the treatment may be simulated – i.e., performed on a non-treating machine, to ensure the correct treatment will be delivered later.

Treatment may be given on an out-patient or in-patient basis. It is imperative that the prescription and treatment plan is adhered to as any missed treatment may affect success. The patient usually receives the same treatment each day for a course of treatment, which can last up to six weeks. Treatment is monitored regularly and may be adjusted if the patient suffers from adverse side effects or loses weight. To receive the radiation therapy, you will lie on a couch under the machine, and be asked to remain still during the actual treatment.

Once all is ready, your radiation therapist leaves the room to monitor your treatment. The gantry of the linear accelerator begins to rotate around you as you breathe normally. You may see and hear this movement, but the treatment is completely painless. Radiation cannot be seen or felt while it is being given. The actual delivery of the radiation treatment itself, once the patient is in position, often just takes a few seconds. Naturally, the set-up processes surrounding the radiation delivery itself can make an entire session several minutes long.

During treatment a process of verification takes place. By using built-in imaging, images are taken of the treatment site. These images are used to verify both the patient position and the accuracy of the treatment beam.

Once your course of treatment is completed, you attend follow-up clinics for up to five years to monitor your disease and manage any post-treatment side effects. Initially, you will come to our center. Annual follow-ups may then be conducted by the specialist who sent you for treatment.

Find Cancer Care Close to Home

Radiation therapy, while an essential tool in cancer treatment, can lead to various side effects, which may vary in severity depending on several factors, including type of radiation, the dose and the location of the treatment. Common side effects often include:

• Localized skin reactions (redness, irritation, peeling or blistering)

• Fatigue

• Temporary changes in treated area’s appearance (e.g. hair loss on neck or head)

• Digestive issues

These side effects are highly indivilualized, and not all patients will experience them to the same extent.

During a session, patients typically don’t feel any pain or discomfort while the radiation is being delivered. The radiation itself is invisible and painless, much like getting an X-ray. Most patients describe the actual treatment as painless and quick, only lasting a few seconds.

Some sensations may occur as a result of the treatment over time. For example, in the days or weeks following radiation therapy, patients may experience localized skin reactions similar to a sunburn, as well as fatigue.

At CHI Saint Joseph Health, we offer the latest, safest and most effective radiation therapies to treat a wide range of cancers. Our board-certified radiation oncologists and technicians will work closely with your cancer care team and you to carefully plan and monitor each treatment to maximize success. We’ll also be right by your side through every phase of treatment to help you feel well and without major changes to your normal routine.

To make an appointment, find a cancer specialist anytime online or explore a CHI Saint Joseph Health cancer center near you.