(Radioterapia)
If you've seen a dentist or been treated for a broken bone, you've experienced radiation firsthand. In everyday life, radiation in the form of X-rays is used to create images of areas of the body that doctors can't see, such as the inside of a tooth or the interior of the chest cavity.
In much higher doses, radiation is used to treat cancer. Radiation therapy (also called radiotherapy, irradiation, or X-ray therapy) works by preventing cells from growing or reproducing, and by destroying them. But parents whose kids need radiation therapy — one of the most common treatments for childhood cancer — often have many questions and concerns about it.
About Radiation Therapy
In radiation therapy, high-energy radiation from X-rays, gamma rays, or fast-moving subatomic particles (called particle or proton beam therapy) is used to kill cancer cells and shrink tumors. Some types of childhood cancer treated with radiation therapy include brain tumors, Wilms tumor, and head and neck cancers.
Besides destroying cancer cells, radiation therapy can also harm normal cells. Normal cells are more likely to recover from its effects, though, and your child's health care team will take extensive measures to carefully monitor radiation doses to protect healthy tissue.
Because every case is different, each child's cancer treatment will also be unique. Some kids receive radiation therapy alone, while others need both radiation and quimioterapia (the use of medicines to destroy cancer cells). And some kids require radiation therapy and surgery to remove tumors or cancerous areas.
How Radiation Is Given
Radiation therapy is administered two ways: externally or internally. Some kids may receive both external and internal radiation, depending on their needs.
External radiation therapy uses a large machine and special equipment that aims very specific amounts of radiation at cancerous tumors or diseased areas of the body. With Internal radiation therapy (also known as brachytherapy, interstitial therapy, or implant therapy), a radioactive substance is injected or implanted into the body at the site of the tumor or cancer cells. In some cases, the material is swallowed.
Most kids receive only external radiation therapy, although those with cancers of the head and neck, uterus, cervix, thyroid, and testes may also undergo internal radiation therapy.
A radiation oncologist (a doctor who specializes in radiation therapy) will work with other health care professionals to decide on the type and dose of radiation therapy that's best for your child.
What Happens During External Radiation Therapy
Receiving radiation therapy for cancer treatment isn't a one-time deal: Kids who receive external radiation usually visit the hospital or treatment center as outpatients 4 to 5 days a week for several weeks, coming in just for the treatment and going home right after. Receiving small daily doses of radiation helps to protect the normal cells from damage, and weekend breaks help the normal cells to recover from the trauma of radiation.
Before the first radiation treatment, a planning session called simulation will help you prepare. Your child will lie on an X-ray table while a radiation therapist uses an X-ray machine (called a simulator) to define the treatment area. Some X-rays or CT scans might be taken, and an area on the skin is marked with ink to highlight the treatment area. This "tattoo" should not be wiped off because it helps to position the radiation for each treatment.
At each external radiation appointment, your child will wear a hospital gown or robe and enter the radiation treatment room, where the radiation therapist will settle your child into position. The therapist will leave, and a large machine will then deliver the exact amount of radiation necessary to kill the cells in the cancerous area. Most of the time that your child spends on the radiation treatment table involves proper positioning — the treatment itself takes only minutes.
Younger kids may have trouble being still during treatment — in these cases, kids may wear a custom body cast or be sedated to help immobilize them. To prevent unnecessary radiation exposure, parents aren't allowed in the treatment room, but you can still be there for your child during therapy. Some hospitals have two-way communication devices so you can talk with and reassure your child, and some even use closed-circuit TVs that allow parents to watch the procedure.
What Happens During Internal Radiation Therapy
Internal radiation treatment usually requires a child to stay in the hospital for several days for careful monitoring. The radioactive material may be placed in small tubes that are implanted into the cancerous tumor or a body cavity, or swallowed or injected into the bloodstream. This can entail a minor surgical procedure requiring anesthesia (for example, when inserting something into the uterus, esophagus, or airways).
You may wonder whether the radiation your child receives will rub off on you or other family members — and whether you can touch, hug, and care for your child during and after treatment. If the treatment is external radiation therapy, there's no need to worry. Kids getting external radiation are not radioactive after treatment, so contact with family members does not need to be restricted in any way.
For kids and teens receiving internal radiation therapy, there may be some restrictions. The radiation in the implant may send high-energy rays outside the child's body, so visitors will need to be protected from exposure. The child will be in a private room, and nurses and visitors can only enter for short periods of time. Your child will have all the necessary care, but the nurses will work quickly to reduce exposure.
Common Side Effects of Radiation
If your child has cancer, you're not only coming to terms with that diagnosis, but probably also worrying about the physical and emotional effects of radiation therapy.
Although the main purpose of radiation is to destroy cancer cells, it can also damage healthy cells. It's this damage to normal cells that results in radiation side effects, most of which are related to the area being treated. The physical side effects of radiation therapy depend on the dose of radiation, the location where it was received, and whether the radiation was internal or external.
Many patients have no side effects at all, but for those who do, most will go away in time, generally aren't serious, and can be controlled with proper treatment.
A child who receives radiation therapy may experience side effects shortly after beginning treatment (called early side effects), such as:
Fatiga
One of the most common side effects of radiation treatment, both during treatment and after, fatigue often begins within a few weeks of the start of treatment and commonly lasts for 4 to 6 weeks after it's completed. Encourage your child to rest and sleep as often as possible, even if resting or sleeping doesn't immediately result in more energy. In the long run, rest helps the body recover from radiation treatment.
Skin Damage or Changes
Skin damage is another very common side effect of radiation treatment, but only in the area receiving the radiation dose. This area may be red, sensitive, or easily irritated in the days, weeks, and months during and after treatment. The skin may swell or droop or the texture may change. The doctor may prescribe ointments or cream to speed healing and reduce irritation, which should go away within 2 to 3 weeks after the end of treatment.
Also, this skin may be more sensitive to sun exposure for months after treatment. There may also be some permanent changes to the color and elasticity of the skin.
How can you help? Dress your child in loose-fitting, soft clothes (such as cotton fabrics) to avoid skin irritation in the treatment area. It's also important to protect the delicate skin from sunlight. During the course of treatment, the irradiated skin should not be exposed to sunlight. After treatment, you should always apply a sunblock with a sun protection factor (SPF) of at least 30 on the affected area.
When it comes to skin care, gentleness is key. Be careful not to irritate the treated skin, and wash it gently with only lukewarm water and mild soap. Avoid rubbing and scrubbing; simply pat the skin dry after bathing. Discourage your child from scratching the area. You should also avoid applying any powders, creams, or lotions to the treated area.
Hair Loss
Radiation therapy to the head and neck may cause hair thinning or hair loss shortly after treatment begins. It's important to remember, though, that radiation anywhere else but the head and neck will not cause the hair on the head to fall out. Losing hair can be scary for kids, especially if they're at an age where it's hard to be different. Getting a shorter haircut may make it less traumatic for your child once hair loss starts. Your child also may feel more comfortable wearing hats, bandannas, baseball caps, scarves, or wigs until the hair grows back — which may happen within 3 months after treatment ends. Although hair loss usually is temporary, it can be permanent.
Sore Mouth and Tooth Decay
The tissues of the mouth may be sore and sensitive and there may be an increased risk of tooth decay if your child received radiation therapy to the head and neck. These side effects usually occur during the second or third week after therapy begins and disappear within a month or so after it ends. The doctor may prescribe a mouth rinse to reduce pain and irritation. Be sure to take your child for regular dental checkups and follow the dentist's advice during radiation therapy.
Gastrointestinal Problems
In the hours following treatment, kids may experience gastrointestinal problems (such as loss of appetite, diarrhea, nausea, and vomiting) if they received radiation treatment to the pelvis or abdomen. Some who receive radiation therapy to the head and neck may have nausea and vomiting.
Even if your child doesn't feel like eating, it's still important to try to make sure he or she gets good nutrition. Offer foods high in nutrients and talk to your doctor about medicines or dietary changes that may alleviate stomach upset and prevent weight loss. Several small meals may be easier for your child to consume than fewer larger ones, and bland foods, such as crackers, broth, and rice, may be easier to digest.
Blood Changes
Radiation therapy may cause low levels of platelets and white blood cells (the cells that prevent bleeding and help the body fight infection) and red blood cells. The doctor will monitor your child's blood counts regularly and prescribe medication or transfusions if necessary.
Some kids who have radiation therapy in the head and neck region also experience long-term or chronic side effects that can occur months to years after the treatment. These long-term effects — which can be temporary but usually are permanent — can include problems with bone growth, fertility, skin changes, and new tumor development, depending on where the radiation was received, the age of the child, and the dose given. Radiation on the brain may affect learning and memory.
Your doctor can offer advice and may prescribe medications to make your child more comfortable during radiation treatment. Make sure you avoid giving your child any medications, including herbal medicines or over-the-counter drugs, without the doctor's OK.
Caring for Your Child
Its side effects can be unpleasant, but radiation therapy itself is painless and causes no discomfort. To alleviate your child's fears before treatment, it may help to have a tour of the radiation department to see the radiation technologists and equipment.
When your child asks questions about cancer or treatment, be honest. Use age-appropriate terms and encourage your child to share his or her feelings. And remember that you're not alone: Doctors, nurses, psychiatrists, psychologists, social workers, child-life therapists, and other members of the cancer treatment team are there to reassure you and your child before, during, and after radiation therapy.
Once radiation treatment is done, it's still important for the doctor to monitor your child's health and progress in follow-up appointments. During these checkups, the doctor will ask if there are continuing side effects or any signs of the cancer recurring.
Coping with childhood cancer can be frightening for kids and parents alike, but remember that many kids treated with radiation therapy go on to live healthy, full lives.
Don't hesitate to discuss your questions and concerns with the doctor. The more you know about how radiation therapy will affect and help your child, the better prepared you'll be.
Revisado por: Donna Patton, MD
Date reviewed: February 2007
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