Long-term Side Effects of Radiation Therapy for Hodgkin's Disease
Dear OncoLink "Ask the Experts,"
Where can I find research information on long-term effects of radiation therapy for Hodgkin's disease to neck lymph nodes, lungs, and heart?
Li Liu, MD, OncoLink Editorial Assistant, responds:
Thank you for your interest and question.
Long-term complications of radiation treatment for Hodgkin's disease (HD) are being encountered with increasing frequency because of the marked improvement in long-term survival. The complications may include, but are not limited to, dry mouth, abnormal thyroid function (hypothyroidism) (New England Journal of Medicine 1991; 325:599), lung scarring (Cancer 1976; 37:2813), infertility for both male and female patients (Internal Journal of Radiation Oncology biology Physics 1986; 12:117; European Journal of Cancer and Clinical Oncology 1985; 21:601), cardiovascular disease (JAMA 1993;270:1949), and second malignancies (New England Journal of Medicine 1996; 334:745) as well as psychosocial problems (Journal of Clinical Oncology 1986;4:805). Complications of treatment are related to the radiation technique used, dose administered, and irradiated volume. Of all late complications of treatment, second malignancies are generally considered to be the most serious, since they not only cause substantial morbidity but also considerable mortality. Almost all types of cancer can be caused by exposure to ionizing radiation, with the exception of chronic lymphocytic leukemia (CLL). Since many patients with HD received chemotherapy in addition to radiation therapy, it is difficult to assess the exact risk of second malignancy from radiation therapy alone. However, over all, the estimated risk for developing a second malignancy after treatment for HD is 3.5 to 6.4 fold higher than general population (Seminar Radiation Oncology 1996; 6:225).
Of all the secondary solid tumors, lung, female breast, and gastrointestinal cancers are the most common ones. The occurrence of leukemia after treatment with irradiation alone is exceedingly rare. Secondary solid tumors usually take longer period to occur (usually > 7 years) than leukemia.
Even though these side effects are worrisome, it is important to know that most patients with HD survive and do not suffer serious long-term effects. Preventative measures such as healthy diet and lifestyle, exercise, and risk reduction from other factors such as tobacco may reduce the chances for some of these to develop. As always, you should maintain close follow-up with your health care team so that these problems, if they develop, can be identified early.