Cigarette smoking and pulmonary function in adult survivors of childhood cancer exposed to pulmonary-toxic therapy: results from the St. Jude lifetime cohort study.

Treatments for childhood cancer can impair pulmonary function. We assessed the potential impact of cigarette smoking on pulmonary function in 433 adult childhood cancer survivors (CCS) who received pulmonary-toxic therapy, using single breath diffusion capacity for carbon monoxide corrected for hemoglobin (DLCOcorr), forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and total lung capacity (TLC). FEV1/FVC median values among current [1.00; interquartile range (IQR): 0.94-1.04] and former smokers (0.98; IQR: 0.93-1.04) were lower than those who had never smoked (1.02; IQR: 0.96-1.06; P = 0.003). Median FEV1/FVC values were lower among those who smoked ≥ 6 pack-years (0.99; IQR: 0.92-1.03) and those who smoked <6 pack-years (1.00; IQR: 0.94-1.04), than among those who had never smoked (P = 0.005). Our findings suggest that CCSs have an increased risk for future obstructive and restrictive lung disease. Follow-up is needed to determine whether smoking imparts more than additive risk. Smoking prevention and cessation need to be a priority in this population.