Fatal pneumopathy after cytostatic treatment for leukemia in children.

Two cases of fatal pneumopathy during cytostatic therapy for acute lymphatic leukemia of childhood, are reported with pathoanatomical lung findings and general clinical features. Histology revealed massed atypical epithelial proliferation in the bronchiolar terminal pathways (tumourlets) with multinucleated polymorphic giant cells beside pulmonary fibrosis. As causative factors for pulmonary chages hypersensitivity reactions, direct toxicity, or pharmacologic effects are discussed. Formal pathogenesis is explained by an impairment of endothelial cells in alveolar capillaries followed by permeability disorders and interstitial edema with disturbed perfusion. Disseminated intravasal microthrombi are frequent. Restitution to integrity appears possible only under favorable conditions. If the exsudative turns into the proliferative phase, intraalveolar and interstitial pulmonary fibrosis may develop with atypical epithelial proliferations. The prognosis of cytostatics-induced pneumopathies depends essentially on the time when it is diagnosied.