Long-term pulmonary disease among Swiss childhood cancer survivors

Background: Pulmonary diseases are potentially severe late complications of childhood cancer treatment that increase mortality risk among survivors. This nationwide study assesses the prevalence and incidence of pulmonary diseases in long-term childhood cancer survivors (CCS) and their siblings, and quantifies treatment-related risks.

Methods: As part of the Swiss Childhood Cancer Survivor Study, we studied CCS who were diagnosed between 1976 and 2005 and alive at least 5 years after diagnosis. We compared prevalence of self-reported pulmonary diseases (pneumonia, chest wall abnormalities, lung fibrosis, emphysema) between CCS and their siblings, calculated cumulative incidence of pulmonary diseases using the Kaplan-Meier method, and determined risk factors using multivariable logistic regression.

Results: CCS reported more pneumonias (10% vs. 7%, P = 0.020) and chest wall abnormalities (2% vs. 0.4%, P = 0.003) than siblings. Treatment with busulfan was associated with prevalence of pneumonia (odds ratio [OR] 4.0, 95% confidence interval [CI] 1.1-14.9), and thoracic surgery was associated with chest wall abnormalities and lung fibrosis (OR 4.1, 95% CI 1.6-10.7 and OR 6.3, 95% CI 1.7-26.6). Cumulative incidence of any pulmonary disease after 35 years of follow-up was 21%. For pneumonia, the highest cumulative incidence was seen in CCS treated with both pulmotoxic chemotherapy and radiotherapy to the thorax (23%).

Conclusion: This nationwide study in CCS found an increased risk for pulmonary diseases, especially pneumonia, while still young, which indicates that CCS need long-term pulmonary follow-up.