To determine the value of routine, preoperative, fiberoptic bronchoscopy (FB) for diagnosing and treating patients (pts) with solitary pulmonary nodules (SPNs), we retrospectively reviewed the records of all pts with SPNs undergoing FB at Walter Reed Army Medical Center between January 1986 and December 1989. We defined SPNs radiographically as < or = 6 cm peripheral pulmonary lesions completely surrounded by pulmonary parenchyma. Of 191 charts reviewed, 91 (72 bronchogenic carcinomas [BC], 7 carcinoid tumors, 12 benign) constitute the study population. Fifty-four charts were eliminated because preoperative, clinical-radiologic staging revealed advanced (greater than stage I) BC or extrathoracic malignancy metastatic to the lung (44), the clinicians suspected benign disease and elected medical followup (3), the pt had medically inoperable disease (3), or the pt refused surgery (4). Forty-six charts were incomplete or unavailable. Fiberoptic bronchoscopy revealed one unsuspected vocal cord carcinoma and no occult synchronous BCs. Five pts had submucosal or endobronchial tumors and biopsy specimens showed BC in four of five tumors from which specimens were taken. Four of 66 (6 percent) cytologic evaluations of bronchial brushings or washings diagnosed BC. In pts shown at surgery to have BC, 9 of 30 transbronchial lung biopsy (TBBx) specimens showed BC. Diagnostic yield of TBBx specimens was not improved in the pts who underwent biopsies under fluoroscopic guidance. The 16 FB specimens positive for BC concurred 100 percent with the surgical specimens. The FB findings did not obviate the need for surgery nor alter the surgical stage of BC. A preoperative diagnosis of malignancy did not affect operative time or operative procedure, because many pts required frozen-section biopsy of mediastinal lymph nodes prior to lung resection. At our institution, routine, preoperative FB did not measurably benefit pts with SPNs.