Childhood Hodgkin Lymphoma Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Late Effects from Childhood / Adolescent Hodgkin Lymphoma Therapy
Table 9. Treatment Complications Observed in Hodgkin Lymphoma Survivors continued...
Hodgkin lymphoma survivors exposed to doxorubicin or thoracic radiation therapy are at risk for long-term cardiac toxicity. The effects of thoracic radiation therapy are difficult to separate from those of anthracyclines because few children undergo thoracic radiation therapy without the use of anthracyclines. The pathogenesis of injury differs, however, with radiation primarily affecting the fine vasculature of the heart, and anthracyclines directly damaging myocytes.[19,20]
Radiation-associated cardiovascular toxicity
- Late effects of radiation to the heart include the following:[21,22,23,24]
- Delayed pericarditis.
- Pancarditis including pericardial and myocardial fibrosis, with or without endocardial fibroelastosis.
- Coronary artery disease.
- Functional valve injury.
- Conduction defects.
The risks to the heart are related to the amount of radiation delivered to different depths of the heart, volume and specific areas of the heart irradiated, total and fractional irradiation dose, age at exposure, and latency period.
- Modern radiation techniques allow a reduction in the volume of cardiac tissue incidentally exposed to higher radiation doses. It is anticipated that this will reduce the risk of adverse cardiac events.
Selected studies evaluating cardiovascular toxicity associated with radiation
(Refer to the Cardiovascular Disease in Select Cancer Subgroups: Hodgkin lymphoma section in the PDQ summary on Late Effects of Treatment for Childhood Cancer for information on studies evaluating cardiovascular toxicity associated with radiation.)
Anthracycline-related cardiac toxicity
- Late complications related to anthracycline injury include subclinical left ventricular dysfunction, cardiomyopathy, and congestive heart failure.
- Increased risk of doxorubicin-related cardiomyopathy is associated with female gender, cumulative doses higher than 200 mg/m2 to 300 mg/m2, younger age at time of exposure, and increased time from exposure.
- Prevention or amelioration of anthracycline-induced cardiomyopathy is of utmost importance because the continued usage of anthracyclines is required in cancer therapy in more than one-half of children with newly diagnosed cancer.[26,27]
- Dexrazoxane (a bisdioxopiperazine compound that readily enters cells and is subsequently hydrolyzed to form a chelating agent) has been shown to prevent heart damage in adults and children treated with anthracyclines. Studies suggest that dexrazoxane is safe and does not interfere with chemotherapeutic efficacy.
- Studies of cancer survivors treated with anthracyclines have not demonstrated the benefit of enalapril in preventing progressive cardiac toxicity.[29,30]