Radiation‐induced lung fibrosis after treatment of small cell carcinoma of the lung with very high‐dose cyclophosphamide

Abstract

Twenty‐five previously untreated patients with small cell carcinoma of the lung were treated with cyclophosphamide 160 to 200 mg/kg (with autologous bone marrow support) followed by radiotherapy (4000 cGy) to the primary site and mediastinum. No other treatment was given until relapse occurred. Nineteen patients were assessable at least 4 months after radiotherapy; of these, 15 (79%) developed radiologic evidence of fibrosis, which was symptomatic in 14 (74%). The time of onset of fibrosis was related to the volume of lung irradiated. A retrospective analysis was made of 20 consecutive patients treated with multiple‐drug chemotherapy and an identical radiotherapy regimen as part of a randomized trial. Radiologic and symptomatic fibrosis was one half as frequent (35%) as in the high‐dose cyclophosphamide group. Very high‐dose cyclophosphamide appears to sensitize the lung to radiotherapy and promotes the production of fibrosis. Copyright © 1985 American Cancer Society