Pulmonary function impairment measured by pulmonary function tests in long-term survivors of childhood cancer

Background: Childhood cancer survivors (CCSs) have an increased risk of morbidity and mortality. The prevalence and risk factors of pulmonary function impairment were investigated in a large cohort of CCSs treated with potentially pulmotoxic therapy with a minimal follow-up of 5 years after diagnosis. Methods: The study cohort consisted of all adult 5-year CCSs who were treated with bleomycin, pulmonary radiotherapy and/or pulmonary surgery in the Emma Children's Hospital/Academic Medical Center between 1966 and 1996. Pulmonary function tests were performed to diagnose obstructive and restrictive pulmonary function impairment, and diffusion capacity impairment. Results: The study population consisted of 220 out of 248 eligible CCSs, of whom 193 (87.7%) had performed a pulmonary function test at a median follow-up of 18 years after diagnosis. 85 (44.0%) out of 193 CCSs developed a pulmonary function impairment. Pulmonary function impairments occurred in all treatment groups. Most prevalent were restrictive pulmonary function impairment (17.6%) and a decreased carbon monoxide diffusion capacity (39.9%). Multivariate logistic regression models showed that, compared with bleomycin treatment only, treatment with radiotherapy, radiotherapy combined with bleomycin and radiotherapy combined with surgery were associated with the highest risk of pulmonary function impairment. Conclusions: The prevalence of pulmonary function impairment in long-term adult CCSs who received potentially pulmotoxic therapy is high. Bleomycin, pulmonary radiotherapy and pulmonary surgery are all associated with pulmonary function impairment. Pulmonary radiotherapy, especially in combination with bleomycin or surgery, is the most important risk factor. This emphasises the need for adequate counselling and follow-up for this patient population.