External beam radiation therapy (EBRT) is a localized treatment that uses high-energy radiation beams, typically from a linear accelerator, to target and destroy cancer cells while sparing healthy tissue. It is often administered daily over several weeks as an outpatient procedure. Preparation is fundamental to the success of EBRT, helping maximize the precision of treatment delivery and minimize patient stress and potential side effects.
Initial Medical Mapping and Planning
The first step in preparing for EBRT is a detailed process called simulation. This session maps the precise location of the tumor and the surrounding healthy organs that must be protected. The team uses advanced imaging, most often a computed tomography (CT) scan, and sometimes magnetic resonance imaging (MRI) or positron emission tomography (PET), to acquire three-dimensional data of the treatment area.
During the simulation, the patient is positioned on a table in the exact posture they will assume for every daily treatment. To ensure this position is reproducible, the team uses custom-made immobilization devices, such as molded plastic masks for the head and neck, or specialized body cradles and foam casts. These devices keep the body still and consistent throughout the entire course of therapy, which is essential for accurate radiation delivery.
Small, permanent skin markings, usually tiny tattoos, are placed on the patient’s skin to act as external reference points. These markings align with precise laser systems in the treatment room, serving as a daily guide for the radiation therapists to position the patient accurately. The data acquired during this simulation is transferred to a computer planning system, where a medical dosimetrist and a medical physicist work with the radiation oncologist to design a personalized treatment plan. This plan determines the optimal direction, shape, and intensity of the radiation beams to deliver the prescribed dose while adhering to dose constraints for nearby sensitive organs.
Optimizing Physical Health and Routine
The patient’s physical health status before treatment, often called prehabilitation, influences how well they tolerate and recover from EBRT. Maintaining adequate nutrition is a primary focus, as the body requires sufficient calories and protein to repair cellular damage caused by radiation. Patients should prioritize a balanced diet rich in lean proteins, whole grains, and a variety of fruits and vegetables to help preserve muscle mass and support the immune system.
Hydration is equally important, with a recommendation to consume three to four quarts of liquid daily, especially water, to help flush toxins and mitigate side effects like fatigue or nausea. Reviewing all current medications, vitamins, and herbal supplements with the radiation oncologist is required to identify and avoid any substances that could interfere with the treatment’s effectiveness or exacerbate side effects.
Proactive skin care is advised, particularly for the area receiving treatment. Although some older advice suggested avoiding all topical products, current research indicates that a thin layer of recommended, non-irritating moisturizers helps minimize skin reactions. Patients should use only gentle, unscented soaps and pat the skin dry, avoiding rubbing or scrubbing the treatment area. Protecting the skin from sun exposure is highly recommended, as radiation makes the treated area sensitive to ultraviolet light.
Managing Logistics and Support Systems
The commitment to a daily treatment schedule for several weeks requires careful logistical planning to reduce unnecessary stress. Reliable daily transportation to and from the treatment center must be secured, as most EBRT courses involve five treatments per week. For patients who may feel fatigued or anxious, arranging for a family member or friend to provide transportation is a helpful strategy.
Work, childcare, and other responsibilities often need temporary adjustment to accommodate the daily appointments. Appointments typically take 15 to 30 minutes, with most of that time spent on setup. Establishing a robust support system, which may include delegating household tasks or arranging for external support like childcare, prevents the treatment schedule from becoming overwhelming.
Financial concerns should be addressed before treatment begins by consulting with the hospital’s financial counseling or social work services. This involves verifying insurance coverage, understanding potential out-of-pocket costs, and exploring any available assistance programs. Emotional support from friends, family, or support groups provides a network for sharing experiences and managing the psychological aspects of therapy.
What to Expect on the First Day
The first day of treatment is distinct from the planning session and begins the active delivery phase. Patients should wear comfortable, loose-fitting clothing that can be easily removed or adjusted, as they may be asked to change into a gown. Upon check-in, the radiation therapists will guide the patient to the treatment room, which houses the linear accelerator.
The therapists carefully position the patient on the treatment table, using the immobilization devices and aligning the external skin markings with the room’s laser lights. The actual delivery of the radiation beam is painless and often lasts for only a few minutes. During this time, the patient must remain completely still, though they can breathe normally unless specific breathing instructions were given during the simulation. The therapists monitor the patient via a camera and communicate through an intercom system from the shielded control room.