Background and objective: We aimed to examine the frequency of pleural adhesions and to determine their relationship with pleural tumor burden, pleural fluid (PF) biochemistries, PF cytologic yield, and survival in patients with malignant pleural effusion (MPE).
Methods: We performed retrospective analysis of 540 consecutive patients with MPE who underwent medical thoracoscopy. Pleural lesion rating and grade of pleural adhesions based on a thoracoscopic score model were recorded.
Results: Sixty percent of patients with MPE were found to have adhesions in the pleural space. The sensitivity of PF cytology was 71% if there were no pleural adhesions, and 20% if the maximum adhesion score was reached (p < 0.01). The extent of pleural adhesions correlated positively with the pleural tumor burden, and inversely with PF pH. The median survival of patients with minimal or no adhesions in the pleural space was 9 months as compared with patients with the highest grade of adhesions, whose median survival was 5 months (p < 0.01).
Conclusion: MPE are often loculated. The higher the grade of pleural adhesions, the greater the tumor burden exists, and paradoxically the lower the PF cytologic yield. The presence of pleural adhesions in MPE implies a poor prognosis.