RADIATION THERAPY

Radiation therapy is a type of cancer treatment that uses intense energy beams to kill cancer cells. Radiation therapy mostly uses X-rays, but protons or other forms of energy may also be preferred.

The term “radiation therapy” mostly refers to external beam radiation therapy. During this type of radiation, high-energy beams come from a machine outside your body that aims the beams at a precise point on your body. During a different type of radiation therapy called brachytherapy, radiation is placed inside your body.

Radiation therapy damages cells by destroying the genetic material that controls how they grow and divide. While both healthy and cancerous cells are damaged by radiation therapy, the goal of the therapy is to destroy as few healthy cells as possible. Normal cells can repair most of the damage caused by radiation.

Why is radiation therapy done ?

More than half of people with cancer receive radiation therapy as part of their cancer treatment. Doctors use radiation therapy to treat almost any type of cancer. Radiation therapy may also benefit the treatment of some benign, non-cancerous tumors.

How is radiation therapy used in people with cancer?
Your doctor may recommend radiation therapy as an option at different times during your cancer treatment and for different reasons, including:
• As the sole (primary) treatment for cancer
• Before surgery to shrink a cancerous tumor (neoadjuvant therapy),
• To stop the growth of remaining cancer cells after surgery (adjuvant therapy),
• Used in conjunction with other treatments, such as chemotherapy, to kill cancer cells
• In cases of advanced cancer, the doctor may recommend this treatment method to alleviate the symptoms caused by the cancer.

Radiation therapy can also help treat symptoms when the cancer has spread. At this point, radiation is part of palliative care aimed at relieving a person’s symptoms and improving their quality of life. It can also prolong a person’s life in some cases.
Palliative radiation therapy usually involves lower doses and fewer treatment sessions than curative therapy. For example, in some people with bone cancer, palliative radiation therapy can prevent painful tumors from developing.

Risks

The side effects of radiation therapy depend on which part of your body is exposed to radiation and how much radiation is used. Some patients experience few or no side effects. Most side effects are temporary, controllable and usually disappear over time after treatment ends.

Common side effects that may occur in the body after treatment include:
• Hair loss at the treatment site (sometimes permanent), skin irritation at the treatment site, fatigue
• Dry mouth, thickened saliva, swallowing difficulty, sore throat, changes in food flavor, nausea, mouth sores, tooth decay
• Swallowing difficulties, coughing and shortness of breath
• Nausea, vomiting and diarrhea
• constipation, urinary tract irritation, frequent urination, sexual dysfunction
Some side effects may occur later. For example, in rare cases, a new cancer (second primary cancer) different from the first cancer treated with radiation may develop years later. You can ask your doctor about possible short- and long-term side effects that may occur after treatment.

1. THERAPY OF OUTER BEAM RADIATION 

This is the most common type. It contains an external machine that emits a beam of radiation aimed at the treatment area. Depending on the situation, various forms are available.For example, high-energy rays can target cancer that is deeper in the body.

2. INTERNAL RADIATION THERAPY

There are different types of internal radiation therapy. Both involve implanting or introducing a radioactive substance into the body.
Brachytherapy involves placing a radioactive implant in or near cancerous tissue. The implant can be temporary or permanent. Another type of internal radiation therapy involves receiving an injection of radioactive fluid. The aim is to limit the degree of radiation exposure to healthy tissue surrounding the cancer. For example, doctors may recommend this treatment for prostate or ovarian cancer.
Your doctor may recommend both main types of radiation therapy, depending on the type of cancer or the condition of the disease. The decision on which treatment to apply will depend on:
• Cancer type
• The size of the tumor
• Location of the tumor, including nearby tissue types
• Age and general health of the person.

How do you prepare ?

Before starting external beam radiation therapy, your healthcare team will guide you through the planning process to ensure that the radiation reaches the sensitive point in your body where it is needed.

Planning typically includes:

Radiation simulation: During the simulation, your radiation therapy team works with you to find a comfortable position for you. It is imperative that you lie down during treatment. That’s why it’s vital to find a comfortable position. To do this, you lie on a special table like the one used during radiation therapy. Cushions and restraints help to properly position and keep you still. Your radiation therapy team will mark the area of your body that will be exposed to radiation. Depending on your situation, you can make temporary markings with a marker or use small temporary tattoos.

Scan planning: Your radiation therapy team will have you undergo computed tomography (CT) scans to identify the area of your body to be treated. After the planning process, your doctor and the team who will administer the radiation therapy decide what type of radiation and at what doses you will receive, depending on your cancer type and stage, your general health and the goals of your treatment. The precise dose and focus of the radiation beams used in your treatment have been carefully planned to maximize radiation to your cancer cells and minimize damage to surrounding healthy tissue.

What are the expectations from radiation therapy?

External-beam radiation therapy is usually performed using a linear accelerator, which is a machine that directs beams of high-energy radiation into your body.
As you lie on a table, the linear accelerator moves around you to deliver radiation from several angles. The linear accelerator can be adjusted to your specific situation to deliver the precise dose of radiation your doctor has determined.
You will usually receive ambulatory external beam radiation for five days a week within a set time frame. In most cases, treatments are spread over several weeks to allow healthy cells to heal between radiation therapy sessions.
Each treatment session is expected to last approximately 10 to 30 minutes. In some cases, a single treatment may be used to reduce pain or relieve other symptoms associated with more advanced cancers.
During a treatment session, you lie in the position designated for the radiation simulation session. Molded systems are used to hold you in place. The linear accelerator machine can rotate around your body to reach the target from different directions. The machine makes a buzzing sound.
During the treatment, which takes only a few minutes, you can stop and breathe normally. For some patients with lung or breast cancer, you may be asked to hold your breath while the machine performs the treatment.
Your radiation therapy team will be in a room with video and audio connections, so you can talk to each other. You should speak up if you are uncomfortable, but you will not feel any pain during your radiation therapy session.

Conclusion

If you are receiving radiation for a tumor, your doctor may order periodic scans after treatment to see how your cancer is responding to radiation therapy. In some cases, your cancer may respond immediately to treatment. In other cases, it may take weeks or months for the cancer to respond. In some cases, radiation therapy may not help to patient.
Discuss any concerns with your doctor and ask as many questions as possible. Understanding what to expect from treatment can aid in treatment. Do not forget to have regular check-ups for your health.