Cancer, Health,

Common Side Effects of Radiation Therapy And How To Prevent Them

Many patients fear undergoing radiation therapy because they have heard stories of complications and adverse effects that make the cure sound almost worse than the disease. While adverse effects do occur, constantly improved techniques and machines have done much to minimize complications. In addition, thoughtful preplanning can eliminate or minimize many of the common complications. For example, mouth sores, radiation-induced dental cavities, and tooth loss are relatively common adverse effects of radiation therapy of the head and neck region. Poor dental hygiene worsens the problem. By receiving needed dental care before radiation therapy, having needed preparatory tooth extractions and using fluoride during the course of treatment, many radiation-related dental problems can be avoided.

During radiation therapy, sores or ulcers (mucositis) often develop in the mouth, throat, intestines, genital areas and other parts of the body that are covered by delicate mucous membranes. Mucositis often develops among patients undergoing radiation therapy for cancers of the head and neck, lung, esophagus, and abdominal organs. This can be a serious problem when patients have difficulty eating because of mouth sores. If a cancer patient is unable to eat, he or she is likely to become malnourished and further weakened. Mouthwashes, lozenges, frequent examination for thrush or other fungal infections, good oral hygiene, and soft diets all are measures that minimize this potential side effect of radiation therapy.

Women undergoing radiation of the pelvic cavity to treat cancers of the cervix, body of the uterus, vagina or other pelvic organs may develop rectal ulcers, fistulas, bladder ulcers, diarrhea, and colitis. Simple measures such as douches with vinegar diluted with warm water, stool softeners, good hygiene, and, when indicated, dilation of the vagina to prevent the development of adhesions, will help prevent or minimize complications. Antibiotics also may be recommended to prevent abscesses in cases where infection might be a problem.

Nausea and vomiting, side effects that have often been exaggerated in the media, can be minimized by timing of treatments and the use of antinausea drugs. When nausea and vomiting do occur, they tend to be short-lived.
Postirradiation cataracts can be prevented by proper screening of the eye when cancers of nearby structures are being treated. As noted earlier, the lungs are particularly vulnerable to complications from radiation. Radiation pneumonitis, an inflammation of the lung tissue, may result in reduced lung function but this is more common in patients who have preexisting lung problems such as bronchitis. Most radiation pneumonitis subsides in time, except in very weakened patients, and it is not always an indication to avoid further radiation therapy.

Since radiation passes through the skin to reach its ultimate target, it is understandable that the more obvious effects of radiation therapy appear in the skin. At first no reaction is seen, but as the radiation therapy continues, redness (erythema) and darkening caused by increased pigmentation appears in the exposed skin areas. The redness itself is a relatively minor problem and can be minimized by using vitamin A and D ointment or a mild (1 percent) hydrocortisone cream for more intense cases. (Before applying any cream or ointment, be sure to consult your doctor or radiation therapist; lotions or alcohol should never be used for any radiation skin reaction.) The radiation burns that sometimes occurred in the past are now rarely seen. Following radiation treatment, however, the skin may be unusually sensitive to the sun, therefore it is a good idea to avoid exposure to the sun or to apply a sunblocking lotion or cream if the sun cannot be avoided.

After about four weeks of therapy, a second skin reaction may appear; namely, peeling of the exposed skin. If the hair follicles are not swollen, the peeling will be dry; if the hair follicles are swollen, moist peeling and crusting of the skin can be expected. Both these reactions can be treated by following basic dermatologic principles. If the outer skin is dry and intact, it should be kept that way with cornstarch do not use talcum powder. If the outer skin is moist and peeling, the surface should be treated with mild saline soaks and gentle soap and water to remove crusts and dead skin. Severe moist peeling may, in some cases, necessitate halting the radiation therapy until healing occurs. Skin ulcers caused by destruction of small areas of skin should be treated by a physician; however, they are almost always self-limited and not a cause for undue alarm.

Some skin problems do not show up for many years. For example, several years after the radiation therapy, the tissues just beneath the skin may become hard and fibrous, making the area feel somewhat thickened. This is particularly true if a shallow tumor has been treated, or if a large radiation dosage was administered just below the skin surface. Sometimes the skin slowly becomes white, scarred, and thin. This is the result of destruction of the small capillaries that run through the skin. Later, occasional small visible surface blood vessels may form, a condition called telangiectasis. If these are cosmetically troublesome, they can easily be removed by plastic surgery.
In treating cancers of the skin itself, remarkably fine cosmetic results can be obtained by using electron beam radiation. This type of radiation employs subatomic particles, which penetrate only shallow depths of human tissue. By using appropriate shields and protective molds, cancers of the skin, lips, eyelids and nose can be effectively treated without the scarring that may occur from surgical removal. Very low dosage conventional X rays also may be used to treat skin cancers with good cosmetic and medical results.