ANALYSIS OF INITIAL NON-CONCLUSIVE THORACOSCOPIES WITH A DIAGNOSIS OF MALIGNANCY OBTAINED DURING LONG-TERM FOLLOW-UP OF RECURRENT EXUDATIVE PLEURAL EFFUSIONS

Introduction: The association between cancers and exudative pleural effusion(EPE) is not well established in the literature(3-20%). Our objective was the analysis of thoracoscopies(TC) with initial nonspecific pleuritis(NSP), that manifested as malignant during long-term follow-up. Methods: we reviewed patients with recurrent EPE diagnosed of NSP by thoracoscopy between Feb/82-Jun/17. We investigated demographic characteristics, pleural fluid analysis and thoracoscopy findings of those patients with diagnosis of neoplasia obtained during follow-up. Results: A total of 676 consecutive patients were reviewed, of which 428(63%) were diagnosed of pleural malignancy on the first thoracoscopy. 187(28%) patients were excluded from this study because they had a benign diagnosis or were lost in less than 6 months follow-up. Sixty-one(9%) were classified as NSP at thoracoscopy and were revised periodically thereafter(median:22.4 months, range:6-93). Mean age was 62.49 ± 12.43, 33(54.1%) were men. The majority did not have comorbidities(52.4%). The frequent comorbidities: previous cancer 21(34.4%), heart failure 6(9.8%) and 4(6.6%) asbestos exposure. During the follow-up,37 cases(61%) of NSP were diagnosed of malignancy and considered as FN. Presence of heavy adhesions that prevented complete exploration of the pleural cavity was higher in the FN cases. In 24 cases(39%) the diagnosis of NSP was maintained. Conclusions: With initial suspicion of malignancy, a long-term surveillance should be established in NSP, especially in those patients with problematic exploration of the pleural cavity (presence of thick adhesions in the pleural cavity).