PMH's Dr. David Hodgson and colleagues from across the province have found strong evidence pointing towards a high risk of cardiac hospitalization (CH) following mediastinal radiation therapy (RT)--radiation to the area between the lungs where the heart, esophagus and windpipe are located--and doxorubicin-based chemotherapy in Hodgkin lymphoma (HL) patients, especially among those patients with pre-existing heart disease. These findings have important implications for medical teams when weighing treatment options, and in the follow-up of these patients.

The team conducted a population-based study of over 3,900 patients throughout Ontario who were diagnosed with HL from 1988 to 2003. A detailed analysis of a random sample of over 1,000 patients found that the relative cardiotoxicity of different treatments depended on the presence or absence of pre-existing cardiac disease. Other conventional cardiac risk factors--such as high blood pressure and diabetes--were also major contributors to the risk of cardiac complications, and the combination of doxorubicin chemotherapy and mediastinal RT was associated with a significantly higher risk than just doxorubicin chemotherapy alone.

"These findings are an example of the fact that the complications of cancer treatments do no occur in isolation, but vary from one person to the next depending on their pre-existing health," comments Dr. Hodgson. "An effort to reduce the cardiac exposure to radiation in patients with pre-existing cardiac disease is necessary, and medical teams should carefully monitor and treat cardiac risk factors following HL treatment."

Myrehaug S, Pintilie M, Yun L, Crump M, Tsang RW, Meyer RM, Sussman J, Yu E, Hodgson DC. Blood. 2010 Jul 1. [Epub ahead of print]. [Pubmed abstract]. Research supported by the Canadian Institutes of Health Research and Cancer Care Ontario.