THORACOSCOPY IN PLEURAL MALIGNANT MESOTHELIOMA - A PROSPECTIVE-STUDY OF 188 CONSECUTIVE PATIENTS .2. PROGNOSIS AND STAGING

Background. Thoracoscopy appears to be essential in identifying tumors at the beginning of pleural disease. Methods. Between 1973 and 1990, diagnostic thoracoscopy was carried out in a prospective series of 188 patients with malignant pleural mesothelioma (MPM). Biopsy samples we re obtained in all cases, and diagnosis was confirmed by the French pa nel of mesothelioma specialists. In all patients we noted the degree o f involvement of the parietal, diaphragmatic, or visceral pleura, and classified patients according to the Butchart system: Stage I (66 pati ents), II (110 patients), III (4 patients), and IV (8 patients). To as sess prognostic factors, a multivariate analysis of clinical and endos copic findings was performed according to the Cox model. Results. The most favorable factors were absence of weight loss at the time of diag nosis, absence of involvement of the visceral pleura, Butchart Stage I , and epithelial histopathologic type. When Stage I patients were subd ivided into two groups according to whether or not they displayed invo lvement of the visceral pleura, a significant difference in survival w as noted (32.7 months versus 7 months, respectively; P < 0.001). Concl usions. Based on these findings, we propose to divide Butchart or Matt son Stage I into two subgroups, i.e., Stage IA in which only the parie tal or diaphragmatic pleura is involved and Stage IB in which the visc eral pleura is invaded. In the International Union Against Cancer (UIC C) classification, Tl should be used for tumors restricted to the pari etal or diaphragmatic pleura and T2 for tumors with additional involve ment of the visceral pleura.