Pulmonary function in young childhood cancer survivors: results from a prospective multicentre cohort

Background Childhood cancer survivors (CCS) are at risk of pulmonary late effects, but post-treatment lung function remains understudied. Current guidelines recommend screening only for symptomatic survivors treated with lung-damaging treatments. We evaluated pulmonary function, risk factors, and respiratory symptoms in a broad paediatric CCS cohort, including those with standard treatments. Methods In this prospective multicenter study, we included CCS aged 6-21 years, stratified as high-risk (thoracic radiotherapy/surgery, busulfan/bleomycin/nitrosourea chemotherapy, haematopoietic stem cell transplantation [HSCT]) or standard-risk (other systemic treatment). Pulmonary function was assessed via spirometry (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC]), body plethysmography (total lung capacity [TLC]), and diffusing capacity for carbon monoxide (DLCO), expressed as z-scores using Global Lung Initiative references. We assessed respiratory symptoms via questionnaires and analysed treatment associations with pulmonary function using multivariable linear regression. Results With a response rate of 90%, 251 CCS participated (median 7 years post-diagnosis). Mean z-scores for FEV1, FVC, TLC, and DLCO were lower in high-risk (-0.70, -0.91, -0.54, -0.17, respectively) than standard-risk survivors (-0.10, -0.22, -0.17, 0.32). Thoracic surgery and nitrosoureas were associated with lower TLC (-0.53, -1.37), HSCT with reduced FEV1 and FVC (-0.80, -0.84), and thoracic radiotherapy with lower DLCO (-0.63). Respiratory symptoms were reported by 32%, but 64% of those with impaired lung function were asymptomatic. Conclusion Pulmonary function was mostly normal in standard-risk CCS, but impaired in high-risk, although often asymptomatic. These findings support targeted surveillance based on treatment exposure rather than symptoms to guide long-term care.