Radiation Treatments

High-dose radiation therapy, which shrinks the tumors, has been used for 50 years for treating Hodgkin's disease. High-dose radiation is generally reserved for adults. The treatment is highly toxic for children and adds little benefit. In such young age groups it is mostly used if there are large areas of disease in the chest; otherwise, chemotherapy with possibly low-dose radiation is the best option with excellent survival rates.

Radiation Target

Radiation is directed in specific areas depending on the location of the disease:

• If HD is above the diaphragm, radiation is delivered to the neck, chest, and under arms (called the mantle-field) and sometimes to lymph nodes in the upper abdomen or spleen or both. (The use of mantle-field radiation only to the mantle field is usually limited to selected younger patients.) Best candidates may be females under 40 years old with nodular sclerosis or lymphocyte predominant cell types, who have no "B" symptoms, who and have erythrocyte sedimentation rate (ESR) levels less than 50.
• If cancer is below the diaphragm, a so-called "inverted Y" field is sometimes used, in which radiation is directed lymph nodes in the upper abdomen, spleen, and pelvis.

Radiation Treatment Approaches

It is very important that radiation treatments cover the entire diseased area and that the radiation therapy be powerful enough to destroy the malignant cells' capacity to grow and divide. Unfortunately, this means that normal cells are also affected, which can cause serious side effects. Different approaches may be used to prevent complications.

• Devices called planning simulators allow doctors to plan x-ray treatments that accurately conform to the patient's anatomy so that protective shields can be created to precisely protect the regions outside the treatment areas.
• Long-term complications generally occur at higher radiation doses (over 35 Gy). Investigators are studying the doses as low as 20 Gy (in children). Studies are now reporting that radiation alone in doses under 35 Gy can control the disease as well as higher doses in most Stage I and II patients, although some patients may require more aggressive treatment.
• To protect ovaries, a technique called ovarian transposition may sometimes be performed. For example, in one successful small study the procedure was performed within one month of pelvic radiation in women who had either received no chemotherapy or less than two cycles. (Chemotherapy often stops menstruation.) The procedure employs a laparoscope (a thin tube containing tiny instruments and cameras) that is introduced through a small incision. The doctor uses the laparoscope to move the ovaries out of the range of areas being treated with radiation. In this study, four out of five women who desired children achieved pregnancy.

The uterus is a hollow muscular organ located in the female pelvis between the bladder and rectum. The ovaries produce the eggs that travel through the fallopian tubes. Once the egg has left the ovary it can be fertilized and implant itself in the lining of the uterus. The main function of the uterus is to nourish the developing fetus prior to birth.

Complications of Radiation

Infections. Infections may be a particular problem with radiation combined with chemotherapy. All patients should be vaccinated against pneumonia and influenza.

Inflammation in the Lungs. With carefully conducted therapy, the risks for lung complications are small. Lung impairment may not even be evident, and the lungs usually recover after 2 or 3 years.

Click the icon to see an image of the lungs.

Infertility. Radiation therapy to the pelvic area can adversely affect later fertility in women and men. Such negative effects may be worse in women; sperm usually recover within 5 years.

Heart Disease and Stroke. Radiation is associated with a future risk of heart disease, which includes atherosclerosis (hardening of the arteries) and diseases of the heart valves. Lower doses pose less risk. Recent research suggests that adults who survived childhood Hodgkin’s disease have a four times higher risk of having a stroke than healthy patients.

Fatigue. Fatigue is significant and chronic in many survivors. It is more highly associated with intensive chemotherapy, but it also may be a late response to radiation treatment.

Secondary Cancers. Second cancers (such as breast, stomach, lung, melanoma) may develop later in areas within or at the edge of the radiation area. Thyroid, respiratory tract, and digestive tract secondary cancers may affect patients who were treated as children. The risks are twice as high with treatments that are combined with chemotherapy.

Lung cancer in survivors is highly associated with smoking after treatment, and no survivor should smoke. The risk for breast cancer increases significantly in young women after treatment, particularly with high radiation doses and combined chemotherapy and radiation. The risk can persist for 25 years or more after radiotherapy and lifetime monitoring is essential. Some studies of young women who were treated with chest radiation report risks as high as 40 percent. Experts note, however, that newer types of treatments may reduce this risk.

Thyroid Disorders. Hypothyroidism (low thyroid hormone levels) occurs in a number of patients treated with radiation treatments. There is also a 5% chance for hyperthyroidism.

Click the icon to see an image of hypothyroidism.

Click the icon to see an image of hyperthyroidism.

Impaired Growth in Children. Children and adolescents are at special risk for impaired bone growth.