Lung cancer in elderly patients: the role of induced sputum production to obtain a cytological diagnosis.

A single induced sputum sample using hypertonic saline and a ward nebulizer was obtained from 24/26 (92%) patients prior to fibreoptic bronchoscopy for suspected bronchial carcinoma. In 11 of the 19 patients later found to have bronchial carcinoma, positive cytology was found in the induced sputum sample (58% sensitivity), with no false positives (100% specificity). These results are higher than those reported for ordinary sputum samples. They suggest a possible role for this technique in diagnosing bronchial carcinoma in elderly patients in whom bronchoscopy may be considered hazardous, or where this facility is not readily available.