75Se-sodium selenite as a diagnostic aid in the assessment of peripheral pulmonary opacities.

To establish or exclude the diagnosis of bronchial carcinoma a series of 43 patients with peripheral pulmonary opacities was studied by lung scanning after intravenous injection of 75Se-sodium selenite. A diagnosis was ultimately obtained in all patients. The incidence of both false-positive and false-negative results was high. Selenite was taken up by a range of non-neoplastic processes including inflammatory lesions. The value of the procedure in distinguishing bronchial carcinoma from non-neoplastic conditions of the lung that radiographically mimic carcinoma was not confirmed.