The effects of tangential radiotherapy on lung clearance in breast cancer patients

Purpose: The aim of this study was to investigate the effects of tangential radiotherapy (RT) on lung clearance in the patients with breast cancer by using 99mTc-DTPA aerosol scintigraphy. Material and methods: Thirty-three female patients [non-smoker: 20, ex-smoker: 13] performed surgery and systemic chemotherapy for breast carcinoma [47±13 years] were included in the study. All patients underwent 99mTc-DTPA aerosol scintigraphy prior to RT (preRT), midway through RT (midRT) and after RT (postRT). Total dose was 50 Gy in modified radical mastectomy and 60 Gy in lumpectomy (2 Gy/fraction). Posterior dynamic images of lungs were obtained immediately after the inhalation of 99mTc-DTPA aerosol. Results: Pulmonary function tests were normal in three measurements for all cases. In the ex-smokers, there was no significant difference among preRT, midRT and postRT clearance values in both lungs. PreRT lung clearance in non-smoker group did not differ from that in ex-smokers. However, the lung clearance for non-smoker group showed significantly increase following RT. Conclusion: In this study, we observed that tangential radiotherapy caused an increase in the lung clearance in the cases of non-smokers even in non-irradiated lung, and that the effect of RT on lung clearance was closely depended on smoking habit before RT. © 2005 Elsevier Ireland Ltd. All rights reserved