A new method of cancer treatment: Let's learn about Proton Therapy in simple terms

When we learn that a family member or friend has cancer, we feel a great sadness and shock. But at the same time, the question that comes to mind is, "What is the best treatment?" When talking about cancer, the words we have all heard are surgery, chemotherapy, and radiation therapy. Today we are going to talk about a relatively new and very advanced treatment method in the field of radiation therapy. This is called proton therapy or proton beam therapy.

Simply put, what is proton therapy?

Okay, let's explain this very simply. Proton therapy is also a type of radiation therapy used to kill cancer cells. But usually, radiation therapy uses high-energy X-rays or electrons. But proton therapy, as the name suggests, uses high-energy, positively charged particles called protons .

Now you might be wondering, "What's so special about using protons instead of X-rays?" Here's the important thing.

Imagine you're throwing a rock into a balloon filled with water. The rock will pierce the balloon and travel to the other side, right? Traditional radiation therapy is a bit like that. The X-ray beam travels through the surrounding healthy tissue as it travels to the tumor, and after destroying the tumor, it travels through the healthy tissue on the other side. This is called an "exit dose." This can cause some damage not only to the cancer, but also to the surrounding healthy cells.

But proton therapy is like a "magic bullet." This proton beam enters the body, goes to the tumor, uses its full energy to destroy the cancer cells, and then stops there. It does not go beyond the tumor. That means there is almost no "exit dose." As a result, the damage to healthy tissue around the tumor is very minimal. This is the biggest and most important advantage of proton therapy.

This treatment is planned and supervised by a doctor who specializes in radiation oncology. We call him a radiation oncologist . He is the one who decides exactly how deep and with what energy the proton beam should be sent.

What types of cancer is this treatment most often used for?

Because of this precision, proton therapy is not used for all cancers. In particular, this treatment method is chosen for:

• For cancers near the body's most sensitive organs: for example , the brain, spinal cord, eyes, heartWhen there are cancerous tumors close to vital organs, such as the liver, this method is very suitable for treating only the cancer without damaging those healthy organs.
• For childhood cancer: Because children's bodies are still developing, radiation can damage their healthy cells more than adults. Therefore, proton therapy is a great option to minimize the potential side effects (e.g., stunted growth, other cancers) of radiation therapy given to children in the future.

How do you prepare before treatment?

Before proton therapy treatment begins, there is a planning session . This is the most important part of the treatment. This is when your medical team plans everything exactly.

1. Determining the treatment position (Getting in position)

You will be made to lie comfortably on the treatment table. You will have to remain still during the entire treatment. Because even a millimeter of movement can cause the proton beam to go in the wrong place. Therefore, special equipment (immobilizing device) will be used to keep you in the same position.

• Imagine if you were being treated for cancer in your head, you could use something like a special mask that fits your face and head perfectly.
• If it is on another part of the body, you can use something like a pillow (mold/cushion) shaped to that part.

Although these may seem a bit inconvenient, they are essential to ensure that the treatment is targeted.

2. Getting imaging scans

Once you are positioned, a CT scan is performed to see the exact size, shape, and location of the tumor. Sometimes an MRI or PET scan may also be used. These scans are used to plan the exact path of the proton beam using computer software.

At this time, the medical team may make some very small marks on your skin or on the immobilization device, such as with a pen. Don't worry, these are just to help you stay in the same position each time you come in for treatment.

What actually happens during treatment?

The treatment is given in a special room set aside for that purpose. These are some of the things that usually happen.

1. Positioning you: The medical team will have you lie down on the treatment table and prepare you with the immobilizing devices as planned.

2. Taking pictures:Before the treatment begins, a few more images (X-ray or CT) will be taken to make sure you are in the correct position. Then the medical team will go to a separate control room.

3. Giving the treatment: Even though you are alone in the room, they are always watching and listening to you through video cameras and microphones. You can speak up if you feel uncomfortable. There is a large mechanical arm-like part connected to the machine that delivers the proton beam, called a gantry . This gantry rotates around you, aiming the proton beam at the cancer at the most appropriate angles. You may hear a slight noise when the machine is working, but you will not feel any pain .

How long does this treatment take?

The proton beam is actually delivered to your body for a very short time, like a few minutes . But it can take 20-30 minutes or more to position you, scan you, and double-check everything and get you ready.

This treatment is usually given five days a week for several weeks. However, this schedule varies from person to person. Your doctor will give you a specific schedule.

What are the benefits of proton therapy?

As we've discussed before, the biggest advantage is that there's minimal damage to healthy tissue. There are a few additional benefits that come with this. Let's look at them this way.

Is this a successful treatment? What are the side effects?

In terms of success, there is not much difference between proton therapy and traditional radiation therapy. Both have similar success rates. However, as we discussed earlier, research has shown that proton therapy provides better results in some specific cases (e.g., pediatric brain tumors).

When it comes to side effects, it is impossible to say "no side effects at all" . After all, this is a powerful treatment. However, side effects usually occur gradually, after a number of treatment sessions. The side effects that occur depend on the area of ​​the body being treated .

• If the brain is treated: Headaches and memory problems may occur.
• If the stomach or digestive tract is treated: nausea, stomach pain, and diarrhea may occur.
• If treating the mouth or throat : Mouth sores and difficulty swallowing may occur.

What happens after treatment?

When the treatment session is over, the medical team will come in, remove the devices that immobilized you, and help you get off the table. Most people can go home straight after the treatment. The best part is, no radiation will be released from your body . So you can be around other people, even small children, without fear.

It may take several weeks to fully recover, meaning you will be free of side effects and back to normal. This time will vary depending on your condition.

What time do you want to talk to the doctor?

It is very important to maintain regular contact with your medical team during treatment. Especially,

• If the side effects are worse than you expected.
• If you develop new, unexpected symptoms .

Before starting treatment, ask your doctor, "What symptoms should I report immediately if they occur?"

Currently, there are only a limited number of centers in the world that offer proton therapy. This is because the technology is very expensive. And one of the reasons is that it is most beneficial for rare types of cancer. But as more information comes out about the benefits of this technology, this treatment method is likely to become more common in the future.