Introduction Chronic Fibrinous Pleuritis (CFP) is a common histological diagnosis encountered after medical thoracoscopy (MT), particularly in areas with high incidences of mesothelioma. This poses a challenge for clinicians as a proportion of patients are subsequently proven to have an alternative diagnosis. A local review was undertaken to discern the clinical outcome for those diagnosed with having CFP.

Methods A retrospective review of 202 MT performed at a regional pleural unit over a 6 year period was conducted. For those initially diagnosed with CFP, details including further biopsies, length of follow up, final diagnoses and survival times were recorded.

Results Mesothelioma (77), breast (13) and lung (12) were the commonest malignancies encountered. Eighty-four biopsies were consistent with CFP; all were followed up with either CXR, CT (a mean interval of 4.5 months) or both. A further 31 had the diagnosis refined: 19 were subsequently diagnosed with malignancy by alternative methods (4 VATS, 3 Ct guided , 1 axillary lymph node biopsy, 11 progressive radiology). Mean time to repeat biopsy was 6.82 months (95% CI 3.14 to 10.87) and mean follow up was 16.7 months (95% CI 14.06 to 19.46). The remaining 53 patients were alive or passed away due to unrelated causes at time of writing (range of 3 to 86 months).

Conclusion An initial finding of CFP should be investigated further in the right clinical context, particularly where there is still a high suspicion of cancer. Patients must be made aware of this possibility. This study has shown a conclusive diagnosis can be made in a further 15% of patients, in keeping with other studies. Clinicians can be reassured in those with stable symptomology and radiology after a period of observation, though this timeline remains undefined.