Correlation between thoracoscopic presentations and pathological patterns in undiagnosed pleural effusion

Pleural effusion is the most prevalent pleural disorder. One third of pleural effusions are caused by lung cancer. Thoracoscopy is regarded as the most reliable diagnostic method for the evaluation of suspected pleural malignancy. To assess visible pleural characteristics of abnormalities and their locations for malignant and benign pathologies as well as to determine the incidence of malignancy in the apparent normal pleura. This was a descriptive, observational, and cross-sectional research that was performed on 36 cases with undiagnosed exudative pleural effusions prepared for medical thoracoscopy and on whom the cytological analysis was inconclusive, at the thoracoscopic Unit Department of Chest Diseases, Faculty of Medicine Zagazig University, from December 2023 to May 2024. The apparent normal pleura and adhesions were significantly greater in benign effusions than in malignant effusions (p = 0.019 and p = 0.04, respectively), while nodular effusion was significantly greater in malignant effusions than in benign effusions (p = 0.003). Bleeding was significantly greater in malignant effusions than in benign effusions (p = 0.019). As regards the thoracoscopic findings, 24 (66.7%) patients showed nodular patterns, 14 (38.9%) patients showed adhesions, and two (5.6%) patients had pus, while six (16.7%) patients had apparent normal pleura. The costal pleura was the most frequently affected site (88.9%) followed by the visceral pleura (55.6%) then the diaphragmatic pleura (38.9%). Medical thoracoscopy (MT), a minimally invasive and a generally safe treatment, enables the interventional pulmonologist to access the pleural cavity directly and obtain pleural samples under direct view helping in predicting the pathology.