Prognostic significance of flow cytometric DNA analysis in patients with malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) due to environmental exposure to asbestos and erionite is a relatively common cancer in Turkey. In this study, we investigated the value of flow cytometric (FCM) DNA analysis and other prognostic factors such as age and etiologic factor in the patients with MPM, treated with surgery combination chemotherapy radiotherapy. A total of 40 patients with a median age of 50 (range 30-68) were included in the Study. Twenty-nine patients had asbestos exposure in etiology, while 11 had fibrous zeolite (erionite). Paraffin-embedded tumor specimens were studied by FCM for DNA analysis. Twelve patients (30%) had aneuploid tumors and 28 (70%) had diploid ones. Mean S-phase fraction (SPF; %) was 9.1 +/- 1.1 and proliferation index (PI, SPF + G2/M phase; %) was 11.3 +/- 0.9. While the median overall survival (OS) was 10 +/- 2 months (6-14; 95% Q, 1-year survival rate was 45.2%, Only PI was found to be statistically significant for OS in univariate analysis (P = 0.013). PI was also found to be an independent prognostic factor for all patients (P = 0.035). Aneuploidy was significantly higher in erionite group Compared with asbestos group. Male predominance and poor survival were also prominent in erionite group, though not statistically significant. In conclusion, PI is an independent prognostic factor for patients with MPM and the biologic features of the disease may show differences with respect to different etiologies. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.