Therapeutic advances in paediatric oncology have led to an increase in the number of adult survivors of childhood cancers. However, it is not currently known whether their long term health is influenced by the cancer therapies they receive.
In this retrospective cohort study, 14358 five year survivors of cancer enrolled in the Childhood Cancer Survivor Study were studied. All had been diagnosed under the age of 21 with leukaemia, brain cancer, Hodgkin’s lymphoma, non-Hodgkin’s lymphoma, kidney cancer, neuroblastoma, soft tissue sarcoma, or bone cancer between 1970 and 1986. A comparison group consisted of 3899 siblings of cancer survivors. The main outcome measures studied were the incidence of and risk factors for congestive heart failure, myocardial infarction, pericardial disease, and valvular abnormalities in survivors of cancer compared with siblings.
The cumulative incidence of cardiac disorders among childhood cancer survivors are shown in figure 1. Overall, the cumulative incidence of adverse cardiac outcomes in cancer survivors continued to increase up to 30 years after diagnosis.
Figure 1: Cumulative incidence of various cardiac disorders among childhood cancer survivors
Survivors of cancer were significantly more likely than their siblings to report congestive heart failure (hazard ratio (HR) 5.9, p<0.001), myocardial infarction (HR 5.0, p<0.001), pericardial disease (HR 6.3, p<0.001) or valvular abnormalities (HR 4.8, P<0.001). In particular, exposure to >250mg/m2 of anthracyclines increased the relative hazard of congestive heart failure, pericardial disease, and valvular abnormalities by two to five times compared with survivors who had not been exposed to anthracyclines. Also, cardiac radiation exposure (>1500 centigray) increased the relative hazard of all four abnormalities by between two- and sixfold compared to non-irradiated survivors.
A substantial risk for all forms of cardiovascular disease is present in survivors of childhood and adolescent cancers. As this population continues to grow, all healthcare professionals must be aware of the increased cardiovascular risk of this group of patients.
• Mulrooney DA, Yeazel MW, Kawashima T et al. Cardiac outcomes in a cohort of adult survivors of childhood adolescent cancer: retrosepective analysis of the Childhood Cancer Survivor Study Cohort. BMJ 2009 online first