What is Radiation Therapy?
Radiation therapy, also known as radiotherapy, is a highly effective and widely used cancer treatment that uses high-energy beams or particles to destroy cancer cells. The primary goal of radiation is to damage the DNA of cancer cells, which stops them from growing and dividing, eventually causing them to die. While the radiation beams pass through the body, they can also affect normal, healthy cells. However, normal cells have a much greater ability to repair this damage than cancer cells do.
Radiation therapy is a local treatment, meaning it only affects the specific area of the body to which it is directed. It can be used alone with curative intent, or more commonly, as part of a multi-modal treatment plan in combination with other therapies like surgery and chemotherapy. The decision to use radiation therapy is made by a multidisciplinary team based on the cancer’s type, location, and stage.
The Radiation Oncology Team in Turkey
The planning and delivery of radiation therapy are managed by a dedicated team of highly trained specialists. In Turkey, this team collaborates closely to ensure that treatment is safe, accurate, and effective.
- Radiation Oncologist: This is a medical doctor who specializes in treating cancer with radiation. They lead the team, determine if radiation is the right treatment for a patient, prescribe the appropriate radiation dose, and manage any side effects that may arise during treatment.
- Medical Physicist: A physicist with expertise in radiation works behind the scenes with the radiation oncologist. They are responsible for the complex calculations needed to design the treatment plan, ensuring the radiation machine (linear accelerator) is calibrated correctly and that the prescribed dose is delivered precisely to the tumor.
- Dosimetrist: Working under the direction of the radiation oncologist and medical physicist, the dosimetrist uses sophisticated computer software to create the detailed treatment plan that will deliver the radiation dose while minimizing exposure to surrounding healthy organs.
- Radiation Therapist or Technologist: These are the highly skilled professionals who operate the radiation machine and administer the daily treatments to the patient. They are responsible for positioning the patient correctly for each session and ensuring the machine delivers the treatment exactly as planned.
The Radiation Therapy Process: From Planning to Treatment
The process of receiving radiation therapy involves several distinct and carefully orchestrated steps.
1. Consultation
The first step is a consultation with a radiation oncologist. The doctor will review the patient’s medical history, pathology reports, and imaging scans to determine if radiation therapy is an appropriate part of their treatment. They will discuss the goals of the treatment, the specific technique that will be used, the expected timeline, and any potential side effects.
2. Simulation (The Planning Session)
Before treatment can begin, a detailed planning session, called a simulation, must take place. This session is crucial for ensuring the accuracy of the treatment. During the simulation:
- A custom immobilization device is often created. This could be a mesh mask for head and neck cancers or a foam mold for the body. These devices are designed to help the patient lie in the exact same position for every treatment session.
- A CT scan of the treatment area is performed while the patient is in their treatment position. The images from this CT scan will be used as a map for the treatment planning software.
- Small marks, either with a special ink pen or as tiny permanent tattoos, may be placed on the patient’s skin. These marks are used by the radiation therapists to align the patient’s body with the radiation machine’s lasers before each treatment.
3. Treatment Planning
After the simulation, the radiation oncologist, medical physicist, and dosimetrist work together for several days to create the patient’s individual treatment plan. Using the CT images, the oncologist will precisely outline the tumor area to be treated (the target volume) and the nearby healthy organs to be avoided (organs at risk). The physics team then uses advanced software to calculate the optimal angles, shapes, and intensities of the radiation beams to deliver the prescribed dose to the target while sparing the surrounding healthy tissue as much as possible.
4. Treatment Delivery
Radiation treatments are typically given once a day, five days a week (Monday to Friday), for a period ranging from one to eight weeks, depending on the specific cancer and treatment plan. Each daily session is quite short. While the patient may be in the treatment room for 15-20 minutes, most of that time is spent on careful positioning. The actual delivery of the radiation (the “beam-on” time) usually only lasts for a few minutes. The treatment itself is completely painless, much like getting a standard X-ray.
Advanced Radiation Technologies in Turkish Centers
Oncology centers in Turkey are equipped with modern linear accelerators and advanced technologies designed to increase the precision of radiation therapy and reduce side effects.
- Intensity-Modulated Radiation Therapy (IMRT): IMRT is a standard technique used for many cancer types. It is an advanced form of 3D conformal radiation that allows the intensity of the radiation beam to be varied across the treatment area. This enables the radiation dose to be “painted” onto the tumor with great precision, conforming to its complex shape while avoiding nearby sensitive structures.
- Image-Guided Radiation Therapy (IGRT): IGRT is the use of imaging right before or even during a radiation treatment session. The linear accelerator is equipped with imaging technology (like a cone-beam CT) that allows the radiation therapists to take a picture of the patient’s anatomy just before delivering the radiation. This image is then compared to the original simulation CT scan to verify that the tumor is in the exact right position. This allows for tiny adjustments to be made to account for day-to-day variations, ensuring supreme accuracy.
- Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT): These are highly advanced techniques that use extremely focused, high-dose radiation beams to treat small, well-defined tumors in just one to five treatment sessions. SRS is used for tumors in the brain, while SBRT is used for tumors in the body, such as in the lung, liver, or spine. Specialized machines like Gamma Knife®, CyberKnife®, or TrueBeam® are often used for these treatments.
The Goals of Radiation Therapy
Radiation can be used with different objectives at various points in a patient’s cancer journey.
- Definitive or Primary Therapy: Used as the main treatment with the goal of curing the cancer, often in combination with chemotherapy.
- Neoadjuvant Therapy: Radiation given before surgery to shrink a tumor and make it easier to remove completely.
- Adjuvant Therapy: Radiation given after surgery to destroy any microscopic cancer cells left behind and reduce the risk of a local recurrence.
- Palliative Therapy: For advanced or metastatic cancer, radiation is a highly effective tool for palliative care. It is used to shrink tumors to relieve symptoms like pain, bleeding, or pressure on a nerve.
Frequently Asked Questions
1. Is radiation therapy painful?
No, the treatment itself is completely painless. You cannot see or feel the radiation beams. The experience is very similar to having an X-ray or a CT scan. The main challenge is simply lying still in the required position for the duration of the short session.
2. What are the common side effects of radiation therapy?
Side effects from radiation are localized, meaning they only occur in the area of the body being treated. Common side effects include fatigue and skin reactions (redness, dryness, or irritation) in the treatment area. Other side effects are specific to the body part being treated (e.g., mouth sores for head and neck radiation, or diarrhea for pelvic radiation). The radiation oncology team will provide detailed guidance on how to manage these.
3. How long does a course of radiation therapy last?
A typical course of external beam radiation therapy is delivered daily, five days a week, for anywhere from three to seven weeks. The exact duration is determined by the radiation oncologist based on the type of cancer, the total dose required, and the treatment technique being used. Some specialized treatments, like SBRT, can be completed in just one to five days.
4. What does it mean when radiation is given “concurrently” with chemotherapy?
Concurrent chemoradiation means that a patient receives chemotherapy during the same period they are undergoing their daily radiation treatments. In this setting, the chemotherapy is usually given at a lower dose and acts as a “radiosensitizer,” making the cancer cells more vulnerable to being destroyed by the radiation.
5. Can I drive myself to and from my daily radiation appointments?
For most patients, yes. The treatment itself does not immediately affect your ability to drive. Fatigue can build up over the course of treatment, so some patients may eventually prefer to have someone else drive them, but it is generally permissible to drive yourself.
6. What is the purpose of the mask or mold made during the simulation?
The immobilization mask or mold is a critical part of ensuring treatment accuracy. It helps the patient to hold the exact same position for every treatment session. Since the radiation plan is designed based on this specific position, being able to reproduce it perfectly each day ensures that the radiation is delivered precisely to the tumor while avoiding healthy tissue.
7. Who creates the radiation treatment plan?
The treatment plan is created through a collaborative effort. The radiation oncologist contours the target areas and organs to be avoided. Then, a highly skilled dosimetrist and medical physicist use specialized computer systems to design the arrangement of radiation beams that will best meet the doctor’s prescription. The final plan is reviewed and approved by the radiation oncologist before any treatment is delivered.
