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Evaluation and management of solitary pulmonary nodules.

The incidence of malignancy in solitary pulmonary nodules found on routine chest roentgenographic survey is unknown but may be as high as 20 per cent. The greatest dilemma confronting most physicians involved in the primary care of patients with solitary pulmonary nodules is sorting out those nodules that can be safely watched from those that should be surgically removed. Certain roentgenographic features of these nodules have been found to be helpful in diagnosis. The only two features that can indicate benign lesions are the presence of dense or concentric calcifications and the stability of the lesion over a period of more than two years. The final decision to operate or not may depend on comparison with old films. Pulmonary nodules present for more than two years without any change in size can be safely followed without operation. Operation is indicated in most newly discovered noncalcified nodules larger than 4 cm and for lesions causing obstructive symptoms.