Radiation therapy: how it works and when it is prescribed

When a doctor diagnoses cancer, it is always a difficult moment. However, modern medicine has many effective treatments, one of which is radiation therapy. In this article, we will look at how it works, when it is prescribed, what side effects to expect, and how to properly prepare for the procedure.

What is radiation therapy?

This question immediately arises in patients who have been prescribed this treatment. Radiation therapy is a method of destroying cancer cells using ionizing radiation.

Radiotherapy (another name for radiation therapy) works as follows: radiation damages the DNA of cancer cells. As a result, they lose their ability to multiply and die. Healthy cells around the tumor also receive some radiation, but they recover better thanks to their healthy repair mechanisms.

Types of radiation therapy

There are several main types of treatment. Let's take a look at the methods of radiation therapy used in cancer centers.

Remote (external) radiation therapy

Remote radiation therapy is the most common type of this treatment. During the procedure, the doctor places the device at a certain distance from the patient's body and directs the radiation beam to the affected area. How this type of radiation therapy works: the patient lies on a special table, and the device rotates around the body, ensuring the most accurate direction of radiation to the tumor.

The use of the latest technologies, such as intensity-modulated radiation therapy (IMRT) and radiosurgery, minimizes the impact on healthy tissue. Irradiation in remote therapy is controlled by a computer.

Internal therapy

Internal therapy involves the introduction of radioactive material directly into or near the tumor. This method is called brachytherapy. Its advantage is the ability to deliver high doses of radiation precisely to the cancer site without harming surrounding tissues.

Palliative radiation therapy

Palliative radiation therapy is prescribed to alleviate the symptoms of the disease. For example, to reduce pain, bleeding, or other complications caused by the tumor. This approach significantly improves the patient's quality of life.

Radiation therapy contraindications

Before starting treatment, it is important to be aware of all contraindications to this procedure. Although it is one of the safest methods, restrictions and contraindications still exist.

The main contraindications include:

• General exhaustion of the body
• Stage IV cancer with metastases
• Decompensated forms of cardiovascular, renal, and gastrointestinal diseases
• Presence of perforated or disintegrating tumors

Relative contraindications include decreased hemoglobin levels, decreased white and red blood cell counts, and pathological skin changes at the site of irradiation.

However, if you have these contraindications, it does not mean that you are automatically ineligible for treatment. During the consultation, the doctor will decide whether the procedure is necessary for a particular patient.

For which tumors is radiation therapy not indicated?

In general, radiotherapy for cancer is indicated for most types of cancer. However, some tumors, especially those that have already metastasized throughout the body, are better treated with systemic therapy—chemotherapy or immunotherapy.

In addition, if the cancer has spread too widely, remote therapy may be ineffective. In this case, the doctor will suggest a combined approach.

Radiation therapy side effects

Patients at the Oncare clinic ask about the most common complications of radiation therapy. It is important to understand that side effects depend heavily on the location of the radiation, the dose, and the individual characteristics of the body.

Side effects of radiation therapy may include:

• Redness and irritation of the skin at the site of irradiation
• Fatigue and weakness
• Temporary changes in taste
• Dry mouth (if the head or neck is irradiated)

Does hair fall out after radiation therapy? Yes, if the head is irradiated, hair may fall out temporarily.

Pain after radiation therapy does not always occur, but if it does, it can be relieved with painkillers.

When is radiation therapy prescribed?

The need for this treatment method is determined by the oncologist on an individual basis for each patient. Radiotherapy can be prescribed as the primary treatment method or in combination with other approaches.

Radiation therapy after surgery is often prescribed to destroy any remaining cancer cells, as they may remain after surgical removal of the tumor. To enhance the effect of radiation in oncology, it is also combined with chemotherapy.

The main indications for radiation therapy are:

• Primary cancer treatment
• Adjuvant therapy (after surgery)
• Palliative treatment
• Prevention of recurrence

How to prepare for radiation therapy?

Preparation for treatment is an important step that should not be ignored. By following all recommendations, you will make the recovery process after treatment easier for yourself.

First of all, the patient undergoes a CT or MRI scan to clearly determine the size and location of the tumor. Next, special marks are made on the skin (they cannot be washed off) to accurately direct the radiation beam during each session. If necessary, special devices are made for the patient to keep the body still during the procedure.

Psychological preparation is also an important aspect. Talk to a psychologist or other patients about what to expect. This will help you get rid of unnecessary tension and anxiety.

How is radiation therapy performed?

The procedure is generally painless. At our cancer center, this procedure is performed as follows:

1. The patient enters the cabin of a linear accelerator, a device that emits radiation.
2. Medical staff help the patient to assume the correct position using marks previously applied to the body.
3. The staff leaves the cabin, and the doctor monitors the process from an adjacent room through glass and video cameras.
4. The device is turned on for several minutes. The duration depends on the type of radiation.
5. During the session, the patient must lie completely still.

How long does a course of radiation therapy last? It depends on the type of cancer and the stage of the disease. Usually, it is 15 to 35 sessions. They are conducted 5 days a week for 3-7 weeks.

Rehabilitation after radiation therapy

Rehabilitation after radiation therapy is no less important. The recovery period varies from patient to patient.

Get plenty of rest, as your body is expending energy on recovery. Avoid heavy physical activity at the beginning of rehabilitation. After 1-2 weeks, you can start doing simple physical exercises. Remember to have follow-up examinations with your oncologist — they are necessary to monitor the results of radiation therapy. Drink plenty of fluids — this will help facilitate recovery.

Nutrition after radiation therapy

Nutrition after radiation therapy plays an important role in rehabilitation. A proper diet helps the body recover faster and strengthen the immune system. Your doctor will select the necessary diet for you and provide general recommendations for nutrition during this period.

What not to eat during radiation therapy:

• Hot and very cold foods
• Spicy and salty foods
• Fatty and hard-to-digest foods
• Alcohol
• Large amounts of caffeine
• Foods that contain large amounts of sugar

Instead, you should eat:

• Fresh fruits and vegetables (especially those that contain antioxidants)
• Protein (fish, chicken, eggs)
• Whole grains
• Dairy products
• Beverages: water, natural juices

If you have problems with your appetite or questions about nutrition, consult a dietitian.