Outcome of patients with nonspecific pleuritis/fibrosis on thoracoscopic pleural biopsies

Abstract

Medical thoracoscopy is recommended in the investigation of patients with exudative pleural effusions, especially when pleural fluid analysis is uninformative. The histological finding of 'nonspecific pleuritis/fibrosis' is common in thoracoscopic biopsies and presents a great uncertainty for clinicians and patients as the long-term outcome of these patients is unclear, and anxieties about undiagnosed malignancy persist. A retrospective case-note study of 142 patients who underwent medical thoracoscopy over a 58-month period in a tertiary referral centre with a high incidence of mesothelioma. Patients with 'nonspecific pleuritis/fibrosis' were followed up until death or for a mean (±SD) period of 21.3 (±12.0) months. A definitive histological diagnosis was achieved in 98 (69%) patients. A total of 44 (31%) patients had 'nonspecific pleuritis/fibrosis'. Five (12%) were subsequently diagnosed with malignant pleural disease after a mean interval of 9.8 (±4.6) months. All five patients had histologically confirmed mesothelioma. In 26 patients with 'nonspecific pleuritis/fibrosis', no cause for the pleural effusion was discovered. The false-negative rate of thoracoscopic biopsy for the detection of pleural malignancy was 5%, with a diagnostic sensitivity of 95% and negative predictive value of 90%. Pleural effusion recurrence was more frequently associated with a false-negative pleural biopsy result. However, there was no correlation with other patient characteristics or the thoracoscopist's prediction based on macroscopic appearances. Thoracoscopic pleural biopsy is valuable in the diagnosis of pleural malignancies. Patients with 'nonspecific pleuritis/fibrosis' require follow-up as a malignant diagnosis (especially mesothelioma) may eventually be established in approximately 12% of cases.