HIGH-RESOLUTION COMPUTED-TOMOGRAPHY OF THE LUNGS IN IRRADIATED BREAST-CANCER PATIENTS

Fifty-five breast cancer patients underwent high-resolution computed t omography (HRCT) of the lungs before, 8-12 weeks, 6, 9 and 12 months a fter adjuvant radiotherapy. During the follow-up time, 17 of them (30% ) were found to develop minimal parenchymal alterations in the irradia ted lung volume by HRCT evidence. The parenchymal alterations were cla ssified by five scores. Scores 1-4 described chronic radiologic change s, score 5 acute radiologic changes. Three patients presented with acu te radiologic changes (alveolar filling) within the first 3 months aft er radiotherapy. Two did not show any abnormalities at later follow-up s. Chronic radiologic fibrosis (15 patients) was not seen before the s ixth month post irradiation except in 2 cases. There was no correlatio n between acute changes and chronic fibrosis. None of these changes we re seen at a lung dose of less than 40 Gy. The appearance of interstit ial pulmonary lesions secondary to breast irradiation was comparable t o that of other interstitial diseases of the lungs. Chest radiographs were normal in all patients. None of the 55 patients presented with cl inical symptoms.