Endocrine Abstracts

Advances in childhood cancer treatment have led to an overall 5 year survival rate of almost 80%. As a result 1 in 900 adults are now childhood cancer survivors but have increased risk of long-term health consequences. Data from the USA, UK, and Europe have demonstrated a standardised mortality rate of 8.4–10.8. Cardiovascular morbidity (congestive heart failure, myocardial infarction, and strokes) have been reported as the commonest non-neoplastic causes of mortality, with tenfold higher risk than in siblings. Features of the metabolic syndrome are common among childhood cancer survivors even before adulthood. The length of time post oncology treatment, independent of the patient’s chronological age, demographic background and BMI, is related to increased risk of metabolic abnormalities. Particular high cardiovascular risk is reported in childhood cancer survivors of brain tumours and leukaemia treated with cranial irradiation and/or bone marrow transplantation and total body irradiation (BMT/TBI). Possible contributing factors include direct chemotherapy and radiotherapy toxicity; endocrinopathies such as GH deficiency and gonadal failure; adipose tissue dysfunction and physical inactivity. Associations between metabolic abnormalities and abnormal body composition have been described. BMT/TBI is particularly associated with increased cardiovascular risk with abnormalities in body composition (increased visceral and intramuscular fat, reduced subcutaneous fat and lean mass), dyslipidaemia and increased diabetes risk. In two recent studies, we have demonstrated reduced β-cell reserve in addition to increased insulin resistance contributing to abnormal glucose tolerance, but improved fitness and insulin resistance after an exercise intervention in survivors of BMT/TBI. Current data in survivors of childhood cancer would indicate that screening and treatment of modifiable risk factors should be addressed at a much earlier age than currently recommended for the general population. Further studies into the prevention and management of cardiovascular risk in young adult survivors of childhood cancer are required.