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Chris Woolmams / Catherine Woollams
What Is Radiotherapy

Originally published in Issue 2 2006 icon


What Is Radiotherapy, or Radiation Therapy?

Radiotherapy, or radiation therapy, uses high speed ionising radiation, similar to x-rays, to hit the DNA or genetic code of abnormal cells.

If the configuration of the DNA can be damaged or changed, the theory is that it is then most likely to be nonsensical. Thus rather than the cancer cell dividing and copying itself to make more cancer cells, instead the altered cell is full of errors and the gobbledegook is just taken away by the body´s natural defences.

The aim of radiotherapy is to damage as many of the cancer cells as possible while harming only a few of the normal, healthy ones.

For radiotherapy to be most effective, the cancer cell needs to be dividing at the time of the radiotherapy. Of course, this is not always the case, which is why treatments often take place daily for a number of weeks. In that way the doctors hope to catch as many cancer cells dividing as possible.

Unfortunately other cells that are frequently dividing - for example hair cells, stomach lining cells, blood cells - will also be attacked, as will adjacent healthy tissues in the line of the radiotherapy beam.

Why Is It Used?

This depends upon the cancer and the type and size of the tumour. Sometimes the aim is to completely destroy a tumour. Other times it is to reduce a tumour in size and control its division. It may also be used merely to shrink a tumour and reduce symptoms.

Who Has It?

About half of all cancer patients will be offered radiotherapy. It may be used on its own, but is more likely to be used with surgery and/or chemotherapy.

How Much Do You Have?

The dose is very carefully calculated. Obviously the radiologist is trying to minimise the damaged to other tissues. For example, thirty years ago, dosage was such that breast cancer patients might suffer significant damage to heart and lungs from the beam. Nowadays radiotherapy can be more tightly targeted and the dosage depends on several factors, like the type of cancer and the surrounding organs and tissues.

With some cancers, further doses may be given at a later stage.

Are There Different Types of Radiotherapy?

There are different types of radiation and even different ways of delivering it.

Open quotesNot all radiotherapy comes from an external machineClose quotes

Some types of radiation are very tightly targeted to treat just one centimetre of tissue. Other types may be used over a much wider area.

Sometimes radiotherapy is given where there has been a spread to the bones or other tissues - this is called palliative radiotherapy.

On other occasions radiotherapy may even be used where no cancer is seen to exist, but where it might take a hold. This is called prophylactic radiotherapy.

Not all radiotherapy comes from an external machine, some may be contained in implants.

Can You Explain Internal and External Radiotherapy?

External radiotherapy is usually given to outpatients and is used widely for many cancers.

However sometimes it may be given during an operation to treat localised cancers that cannot be completely removed by surgery. This is called IORT (Intra operative radiation therapy).

Internal radiotherapy is also called brachytherapy, and uses radiation which is actually placed in or close to a tumour. The radiation source is usually sealed in a small container, and implanted directly into the body. These ´containers´ can be of varying size and involve tubes, wires and seeds. A stay in hospital may be needed - in effect the patient to a degree is radioactive! If you have concerns here please ask your doctor about safety and contact.

What Are The Energy Forms For Radiotherapy?

The higher the energy of the ionising radiation the deeper into the tissues it can go. However not all organs can take the same dosage.

A package of energy is called a photon and this is divided into fractions.

X-rays were the first type of radiation used, but these have largely been replaced by gamma rays. The x-rays are created by machines called linear accelerators and are best used now with cancers on the surface of the body (lower energy x-rays). For internal organs, higher level x-rays are needed.

Open quotesA package of energy is called a photon and this is divided into fractionsClose quotes

Gamma rays are produced by certain isotopes and release energy at certain defined rates.

Particle beam radiation uses fast-moving sub-atomic particles like electrons instead of photons to treat cancers. Linear accelerators are used but some particle beams can only penetrate a short distance into the body, unlike gamma and x-rays.

What Developments Are Taking Place?

3-dimensional therapy uses computer technology to heighten accuracy and delivery.

Intensity modulated radiation therapy can deliver bursts of energy at different doses to affected and healthier tissues.

Radio protectors are being developed to protect normal cells.

Radio-labelled antibodies are being used as cancer seekers.

What Happens To Me?

All patients will go through a very careful planning stage which may involve lying under a simulator so the medical team can plan exactly how to deliver the correct amount. It may also involve some apparatus - even the making of a mask in the case of a brain tumour - to keep the patient still and ensure accuracy during the radiotherapy.

How Long Does It Last?

Each session of radiotherapy is very short, often just a few minutes.

Does It Hurt?

No, not at all. You feel nothing.

What Are The Side Effects?

Damage to local and surrounding tissues. You should ask and receive an accurate assessment of the level of potential damage.

Both blood and lymph cells are attacked by the radiation resulting in low blood counts and fatigue and lethargy. Your blood count should be monitored and the radiotherapy stopped if it falls too low.

Tiredness may be exacerbated if you have to travel long distances to receive the treatment.

Nausea is also quite common, as is loss of appetite.

A little localised burning may be observed.

In some extreme cases radiotherapy can lead to sterility.

Mouth ulcers may occur. In cases where the stomach lining is close to the beam, extreme nausea may be likely. (Anti-nausea drugs can be used to combat this).

What Can I Do To Reduce The Side Effects?

First you should go into the radiotherapy with your immune system as strong as possible. Take all your antioxidants like chlorella (for beta-carotene), natural total vitamin E, vitamin C, zinc, CoQ10, selenium. Eat a healthy, low animal fat, high vegetable and fruit diet.

Open quotesEat a healthy, low animal fat, high vegetable and fruit dietClose quotes

During the radiotherapy, focus more on B vitamins particularly folic acid which aids DNA repair in healthy cells. Fish, organic eggs, spinach, whole grains.

Keep taking your antioxidants during the radiotherapy. UCLA and MD Anderson have produced reports that antioxidants help kill the bad cells and protect your healthy cells.

Ralph Moss, the American Cancer researcher, has just produced a full investigation paper on the effects of antioxidants during radio and chemotherapy. It is on ´PubMed´ and clearly demonstrates that taking these supplements increases success. If your doctor says otherwise, please ask him to send you the research evidence and we will print it. Meanwhile, the Ralph Moss piece talks about the complete lack of evidence against taking antioxidants.

After radiotherapy the effects may still be working for 3-4 weeks. Then you can start rebuilding your blood count with Echinacea, Essiac and Cat´s Claw. A little organic iron for about seven days will help.

Prior to the radiotherapy, a homeopath may be very useful in helping you prepare. Aloe vera rubbed on the skin each night will reduce the after effects of ´burning´.

Peppermint tea will help with the nausea. The homeopath will be able to help further.

What If I Don´t Feel Like Going?

The dosage of the radiotherapy is planned very carefully to do the correct job. If you miss several sessions it will not be as effective as calculated. You really should do your level best to go to every planned session.

Of course, nausea, depression, fatigue all make you feel like skipping the odd session. It is really important that you get yourself a ´buddy´ before the treatment starts. A family member or good friend, this person can help pick you up on your ´down´ days and cajole you into attending all the sessions.

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