Introduction Over the past several decades there have been significant improvements in the care of patients diagnosed with cancer, particularly in the pediatric age range There are more than 15.5 million survivors of cancer in the United States,1 and in pediatrics specifically, cancer is diagnosed in 15,700 patients younger than 20 years each year (Table 62.1) With current 5-year survival for all types at 80%, this yields approximately 450,000 survivors of pediatric cancer.2 One unintended consequence of the successes of therapy is a growing population of patients at risk for cancer treatment–related cardiotoxicity (CTC), and cardiovascular disease has emerged as a leading cause of both morbidity and mortality in this population.3 Survivors are five to six times more likely than sibling controls to develop cardiovascular disease of all etiologies, including: symptomatic heart failure from both systolic and diastolic dysfunction; asymptomatic ventricular dysfunction; valvar disease; coronary disease; arrhythmias; autonomic dysfunction; vascular changes; and pericardial disease.4,5 Table 62.1 Distribution of Cases of Childhood and Adolescent Cancers in the United States With Common, Potentially Cardiotoxic Treatment Exposures LEUKEMIA Acute lymphocytic leukemia Acute myeloid leukemia LYMPHOMA Hodgkin lymphoma Non-Hodgkin lymphoma Central nervous systemc Neuroblastoma Retinoblastoma Wilms tumor Bone tumorsd Children (0–14 y) Adolescents (15–19 y) Cumulative Anthracycline Dosea Potential Thoracic Radiation Exposure Scenarios 26% 8% Lowb Craniospinal photon radiation 5% 4% High – 4% 15% Low or highb Site dependent 6% 8% Low or highb Site dependent 21% 10% – Craniospinal photon radiation 7% 3% 5% 4% – – – 7% Lowb – Lowb High Site dependent – Select metastatic patients Select metastatic patients Soft tissue sarcoma 7% Germ cell tumors 3% Carcinoma and 4% melanoma 7% 12% 20% Highe – – Select metastatic patients – Site dependent aHigh (cumulative ≥250 mg/m2) and low dose (