Diagnostic accuracy and safety of semirigid thoracoscopy in exudative pleural effusions in Denmark

BACKGROUND: To assess the diagnostic accuracy and the safety of medical thoracoscopy (MT) performed with the semirigid thoracoscope.

METHODS: We retrospectively evaluated patients who underwent MT with semirigid thoracoscope under local anesthesia for unexplained exudative pleural effusion from March 1, 2009 to September 1, 2013 in Denmark.

RESULTS: Sixty-nine patients were retrospectively studied. In 13 patients it was not possible to perform the scheduled MT, in 9 cases due to an insufficient pneumothorax, in 3 due to an insufficient pleural effusion, and in 1 due to a purulent pleuritis. In 56 patients in whom MT was completed, the procedure was diagnostic in 44 cases: malignancy was reported in 26 patients and a benign diagnosis in 18. In the remaining 12 patients a definite diagnosis was not reached, and further testing was required.In an "intention-to-treat analysis" (69 patients in total), the diagnostic accuracy of MT was 63%, the sensitivity for malignancy was 59% [95% confidence interval (CI)=43%-73%], the specificity was 100% (95% CI=86%-100%), and the negative likelihood ratio was 0.41 (95% CI=0.29-0.58). Considering the 56 patients in whom it was possible to complete the procedure, the diagnostic accuracy was 78%, the sensitivity for malignancy was 74% (95% CI=54%-87%), the specificity was 100% (95% CI=83.75%-100%), and the negative likelihood ratio was 0.27 (95% CI=0.15%-0.45%). No mortality was reported.

CONCLUSIONS: MT performed under local anesthesia with a semirigid scope is a simple and safe procedure with an acceptable sensitivity for malignancy.