Thoracoscopy in the diagnosis of pleural effusions.

Between January 1981 and December 1986, thoracoscopies were carried out on 152 patients in order to evaluate the diagnostic accuracy of the technique in cases of pleural effusion. All patients had previously undergone a thoracentesis together with an unguided pleural biopsy but had remained undiagnosed. Of them, 74 cases were confirmed as malignant; the others were benign. In 71 of the 74 cases of malignant pleural effusion, an accurate diagnosis had been obtained from the thoracoscopy and guided pleural biopsy, a diagnostic accuracy of 94.6%. Among 78 cases, diagnosed by the thoracoscopy as benign pleural effusion, there were 63 cases of tuberculosis and 15 of non-specific pleurisy. Nine of the 15 cases of non-specific pleurisy showed no evidence of malignancy after being under observation for between six and 30 months, the remaining six cases being lost in the follow-up. No complication arose in our series. We conclude that thoracoscopy is a safe and useful diagnostic procedure for pleural effusion.