Taking Charge of Your Health: A Guide to Medical Follow-up for Young Adults Who Had Cancer in Childhood

RADIATION THERAPY

Radiation Therapy is the use of high energy rays to stop cancer cells from reproducing. It is often a necessary part of cancer treatment. It affects normal cells and cancer cells during active cycles of cell division. In children, because all cells are dividing for growth, radiation therapy may damage normal body cells in addition to cancer cells. The amount of radiation damage depends on factors such as the type and amount of radiation given, the part of the body treated, the age of the patient at the time of treatment, and the type of chemotherapy or drug therapy used. Individuals treated with high-dose radiation at young ages are at greatest risk for radiation damage.

• Radiation affects normal cells by preventing growth in bone, soft tissues and muscles. Adults who had radiation therapy to one side of the body during childhood may have less fat, muscle and other soft tissues on the irradiated side of the body. This difference, called asymmetry, may become more noticeable with weight gain. Maintaining normal weight will make this problem less noticeable.
  
• When radiation therapy is given to the abdomen, or areas which include the kidney(s) or liver, blood test called chemistry profiles should be done to make sure these organs are functioning normally. The kidney helps regulate blood pressure. Blood pressure is a measure of the push of blood against the walls of the arteries. High blood pressure (hypertension) means the heart is straining to pump blood through the arteries. High blood pressure is unhealthy because it can lead to heart disease, hardening of the arteries and stroke. Any adult who has had radiation to the kidney may be at greater risk for high blood pressure.
  
  Since high blood pressure does not usually have any noticeable symptoms, it is important to have your blood pressure checked several times each year. This can be done at your doctor's office or, perhaps at your place of employment. You can help keep your blood pressure normal by keeping your weight normal, exercising moderately and reducing salt use. This is especially true for adults with a single kidney.
  
• Radiation therapy to the chest may cause lung or heart problems. Depending upon the dose to the heart, problems similar to those experienced generally, may occur at earlier ages. Shortness of breath should be reported to your doctor who may order a pulmonary function test or cardiac evaluations to make sure the lungs and heart are functioning properly. Smoking causes lungs cancer, emphysema and other disorders and should be avoided especially if you had radiation to the chest.
  
• Radiation may increase the risk of developing another cancer in the irradiated area. Your physician should examine the skin, muscles and deeper organs that were so treated. Avoidance of excess exposure to the sun is especially important.
  
• Women who had radiation to the chest should examine their breasts each month and have periodic mammograms starting at age 25.
  
• Radiation to the head may affect the thyroid gland, the eyes, and the teeth. Thyroid palpation (feeling the thyroid), should be done as part of your annual physical examination. Eye and dental examinations should be performed yearly. Cataracts may develop earlier than generally expected, but managed easily. Those who had radiation to the mouth and jaw may need closer dental supervision.
  
• While radiation to the ovaries or testes may lead to infertility or sterility, it is not known to cause birth defects in offspring of adults treated for childhood cancer. Newer technologies may offer opportunities for parenting and can be discussed with a specialist.
  
• When relatively high doses of radiation are directed at tissues responsible for producing hormones, such as the thyroid gland, the pituitary gland, and the gonads, the levels of these hormones will need to be evaluated and replacements offered, if necessary.
  
• During young childhood relatively doses of radiation directed to an area that includes the brain, may produce problems with remembering information or learning. A specialist may help with this kind of problem.