Abstract

Histological changes attributable to busulphan were found at necropsy in the lungs of six out of 14 cases of chronic granulocytic leukaemia. The alveoli contained persistent fibrinous oedema converting to fibrous tissue, and also atypical cells. Only one out of seven controls with leukaemia showed fibrinous oedema, and atypical cells were absent. In the lungs from rare cases of fatal pulmonary fibrosis due to busulphan, the histological changes were similar but more severe. It is concluded that busulphan commonly causes fibrinous oedema in chronic granulocytic leukaemia and on rare occasions it becomes severe or persistent enough to cause fatal fibrosis of the lungs. The name busulphan lung is suggested for any of these changes. The term `intra-alveolar fibrosis' should be used instead of `interstitial fibrosis', as it had been called by most previous authors. Despite these findings we consider that this valuable drug should be discontinued only in those very rare instances when intra-alveolar fibrosis shows signs of becoming disabling.