Radiation has been used for the treatment of head and neck cancers since its discovery in the late 1800s. The form of radiation that is currently used in the treatment of cancer consists of very powerful x-rays which are commonly generated in large machines called linear accelerators. These x-rays are exactly the same as those that are used in diagnostic x-rays like chest x-rays or CT scans. However, the actual beam of radiation is much more powerful and very finely directed. In fact, the radiation therapy treatment beams are "steered" to within millimeters of where the treating radiation oncologist wishes it to go.
Radiation treatments are generally delivered on a daily basis, Monday to Friday, for up to six to seven weeks. The actual treatment times are not long, generally in the 15- to 20-minute range. In fact, the actual time receiving the radiation treatment is approximately a minute or two, and most of the daily visits will consist of being set up accurately on the treatment table so the treatments are duplicated exactly each day. The radiation itself cannot be seen, felt or smelled.
The radiation kills the cancer cells by damaging the DNA in those cells. DNA is the substance in each cell which controls its activities in life. Radiation damages cancer cells with each treatment so when they attempt to divide and grow, they are unable to and they die.
Radiation treatments do indeed treat normal tissue along with the cancers; however, the normal tissue is able to repair the potential radiation damage each day and carry on as normal. As the cancer cells are killed during the treatment, the tumor will often be seen to slowly shrink and will hopefully disappear with time.
PRERADIATION THERAPY PROCEDURES
A dental evaluation prior to the start of any radiation therapy is performed. The saliva or spit is very important in keeping the teeth in good condition by keeping bacterial levels down in the mouth and thereby limiting the development of cavities. If the patient experiences dryness of the mouth from the radiation, he or she will be at increased risk for dental problems in the future.
It is therefore essential that all teeth in bad condition be removed and a general dental cleaning be performed prior to the start of any radiation therapy. In addition, it is often recommended that daily fluoride treatment be applied to any remaining teeth along with frequent dental evaluations (every three to six months).
It will be extremely important throughout the treatment to maintain a very good nutritional intake. It is essential for patients to eat well and in large enough quantities to maintain their weight. If this becomes difficult, different aids can be used to help in maintaining weight. One of these aids is called a PEG feeding tube. This is a tube placed directly into the stomach and can, therefore, bypass a sore mouth and throat. These tubes are placed on an outpatient basis and are strictly temporary. Once a feeding tube is no longer needed after therapy is completed, it can be easily removed.
These types of feeding tubes are often used when both radiation therapy and chemotherapy are used in the treatment of the cancer.
THE FUTURE
With the advent of new and ever-changing technology, new techniques are constantly being developed to allow us to deliver the radiation treatments much more accurately and significantly reduce the treatment of normal tissues. A recent development which is now available at our Center is intensity-modulated radiation therapy (IMRT).
This is a very sophisticated way of delivering the radiation so the disease still receives the same cancer-killing high dose, but surrounding normal structures can be significantly spared from the effects of the radiation. In head and neck cancer, this is particularly significant in that the salivary glands can often be spared the effects of radiation and a dry mouth can be averted. This technique allows us to deliver very effective cancer treatment and significantly reduce the side effects of the treatment once considered expected.
However, no matter what treatment you receive at our Center, your progress will be followed extremely closely and you will be cared for by a knowledgeable and caring staff.