Pulmonary function abnormalities in children treated with whole lung irradiation

Abstract

We sought to determine the prevalence of abnormal pulmonary function tests (PFTs) in a cohort of children who had received whole lung irradiation (WLI) for treatment of metastatic disease. This was a retrospective (1988-2003) chart review that included all children treated at our institution with WLI who had undergone PFT. Data abstracted included oncologic diagnosis, radiation dose and fractionation, spirometry (FVC, FEV1, FEV1/FVC, FEF25%-75%), plethysmography (TLC, FRC, RV, RV/TLC), diffusing capacity (DLCO), and respiratory muscle strength (MIP, MEP). PFTs were normalized according to standard deviation (Z) scores. Thirty patients were identified who had one or more PFT. The incidence of mild, moderate, or severe reductions in FEV1 was 30%, 10%, and 10%, respectively, with 50% having normal FEV1. Seventeen percent of patients had mild reduction in total lung capacity (TLC), while 13% and 30% had moderate or severe reductions. Thirty-eight percent had mild reductions in diffusing capacity, while 29% and 14% had moderate or severe reductions. Pulmonary function abnormalities were common in this cohort of children treated with WLI, and may be progressive in nature. Further studies are warranted to identify patients at highest risk.