Early detection of busulfan lung: report of a case

A patient with chronic myelogenous leukemia, treated for two years with busulfan, presented with increasing dyspnea of several months' duration. Despite a normal chest radiograph, there was a markedly reduced carbon monoxide (CO) diffusing capacity (41% of predicted normal) and a restrictive ventilatory pattern on pulmonary function testing. Gallium-67 scanning revealed diffuse uptake in both lungs. The busulfan was discontinued and therapy was changed to hydroxyurea. Three months later the patient was without symptoms, the CO diffusing capacity had risen to 64% (of predicted), and the Ga-67 scan had returned to normal. The chest radiograph remained normal. Despite the lack of biopsy proof, we believe Ga-67 scanning was an aid in the early detection of cytotoxic-induced lung disease in a reversible stage. Gallium-67 scanning may be useful in the early deagnosis of pulmonary injury from cytotoxic agents.