New biomarkers in the selection of patients for talcage of pleural cavity in the palliative therapy of malign pleural exudate

Background: Chemical pleurodesis using videothoracoscopically applied powdered talc under general anaesthesia and selective pulmonary ventilation is the most effective method of palliative therapy for malign pleural exudate. Talc produces an intense systemic inflammatory reaction with the development of aseptic pleurisy. The result is obliteration of the pleural cavity provided there is an intense inflammatory reaction in the pleural cavity and good contact of both pleural leaves. The course of the adherence of pleural leaves can be followed using skiascopy. In routine practice, the course of local inflammatory markers is difficult to evaluate. Selection of suitable patients who will respond to this procedure is another principal obstacle of this surgical method.

Aim: To evaluate the course of local inflammatory changes in the pleural cavity following application of talc and to quantify their dynamics. Selection of specific biomarkers to predict the intensity of inflammation in the pleural exudate for targeted selection of patients suitable for talcage was the second aim of this study.

Materials and methods: 114 patients were retrospectively divided into Group A (N1 = 98) or patients without relapse and Group B (N2 = 16), patients with relapse of exudate formation. The need for repeated thoracic punctures or drainage over the course of a 12-month monitoring period was a criterion of treatment failure. Quantification of the effusion was performed by ultrasonic examination over a one year observational period at 3-monthly intervals. The concentration of soluble CD163 scavenger receptor and soluble Apo/Fas molecule was determined in exudate by ELISA.

Results: Soluble receptors in the 2 groups differed significantly. Group B showed higher sCD163 levels before talcage (P0 = 0.00024), faster dynamic decline in 2 h (P2 = 0.0092) and in 24 h (P24 = 0.0087). During monitoring, decrease in group B was statistically significant at 2 h (P2 = 0.056) and at 24 hrs (P24 = 0.0066).

Conclusion: This pilot study showed that high values of sCD163 and sApo/Fas in the pleural exudate can predict treatment failure. Unsuitable candidates for this type of therapy couldbe selected in this way.