Guidelines for Complications of Cancer Treatment Vol VIII Part B

effusion a mean of 150 days after the completion of thoracicirradiation. The frequency of pericarditis was correlated withthe size of the mediastinal mass, but not with the radiationdose, suggesting that, within the dosage range examined, theamount of pericardium included within the radiation volumewas the most critical variable.The risk of premature coronary artery disease has varied withtreatment technique, use of chemotherapy, age at treatment,and duration of observation. Hence it has been difficult toestablish a clear relationship between radiation dose, volumeof heart irradiated, and coronary-artery disease risk.Investigators at Princess Margaret Hospital found nosignificant increase in the risk of acute myocardial death inpatients with stage I & II disease who received mantle fieldirradiation to a dose of 35Gy with fraction size of 1.8Gy. Inanother study Glanzmann et al. observed a very high risk ofacute myocardial infarction or sudden death of 8.6 (CI, 4.5-15.3) in men who received approximately 40Gy in 1.5-1.8Gyper fraction but observed no excess risk among women whoreceived similar treatment [RR 1.7(CI, 0.04-9.6)]. It was alsoobserved that the excess risk was confined to those who hadknown risk factors for coronary artery disease, includingsmoking, diabetes, hypertension, obesity, orhypercholesterolemia [RR, 2.36 (CI, 1.42-3.68) with riskfactors vs. 0.96 (CI, 0.20-2.77) with no known risk factors].The relationship between radiation dose, cardiac volume andsubsequent development of valvular heart disease has also beendifficult to discern due to the relatively small number of events,prolonged latency period for the development of valvular heartdisease, and evolving radiation techniques. Glanzmann et al.in a study reported the latency of valvular abnormality aftermediastinal irradiation using echocardiographic studies in 144patients. Twenty-nine percent had aortic or mitral valvularthickening apparent on echocardiography. The cumulative304