Long-term survivors of childhood malignancies--aeromedical dilemmas and implications

Survival rates from childhood cancer have dramatically improved over the past three decades; average overall 5-yr survival rates are now > 75%. However, this has been achieved by treatments associated with significant morbidity that may present many years later. This review seeks to delineate the basic information necessary to evaluate flight-training candidates with a history of childhood cancer. We performed a literature review using the Medline database with appropriate search terms related to delayed morbidity and mortality associated with childhood cancer; we did not attempt to evaluate the risk of recurrent cancer. The neurological, cardiovascular, and pulmonary systems were identified areas of aeromedical concern. Central nervous disease and treatment-related effects may increase the risk of seizures or other neurocognitive sequelae. The cardiac toxicity of chemotherapeutic agents such as anthracyclines and radiation may cause late-occurring arrhythmia, cardiac failure, and sudden death, while available screening modalities are of limited value. Pulmonary disease and related treatment effects may cause a 9-fold increase of late-occurring pulmonary fibrosis and lung cancer, with increasing prevalence as long as 25 yr following the cancer diagnosis. Additionally, second malignancies may occur in up to 12.5% of cancer survivors at 25 yr after cancer diagnosis, affecting medical clearance for flight training. In summary, this review discusses the relevant aeromedical issues, including disabilities with specific relevance to the flying environment, risk estimation of late-occurring treatment complications, and possible interactions with occupational exposures in aircrew.