Ninety-five patients with pulmonary parenchymal lesions suggestive of malignancy underwent 103 combined puncture-aspiration biopsies using an 18-gauge Rotex biopsy needle. The over-all sensitivity of the procedure was 90%, and the specificity was 95%, as determined by pathologic and clinical outcome. Needle biopsy was diagnostic in 69 of 77 patients (90%) with malignancy. In 3 patients with a false-negative biopsy result, a second needle biopsy was diagnostic, increasing the yield to 94%. One false-negative biopsy result occurred in a patient with actinomycosis. In the 17 patients in whom no malignancy was found on percutaneous biopsy, subsequent surgical biopsy, culture of aspirate, or stability or disappearance of the lesion within a year or more confirmed the initial diagnosis of nonmalignant disease. Pneumothorax was the only significant complication, requiring tube drainage after 6 biopsies (5.8%). Our study confirms that needle puncture-aspiration is an extremely reliable technique in diagnosing lung malignancy and is adaptable to use in a community teaching hospital.