Factors influencing long-term survival in mesothelioma patients—results of the German mesothelioma register

Between 1987 and 2000, the German mesothelioma register recorded a total of 4,455 patients with malignant mesotheliomas. Survival times for 498 (11.2%) patients were available; 155 patients (study group, 3.5% of the total group) survived for more than 2 years and 343 patients (control group, 7.7% of the total group) survived for fewer than 24 months. Male patients were over-represented in both groups, with 13% of women in the study and 4.4% in the control group. The proportion of pleural mesotheliomas was more than 90% in both groups, with peritoneal cases comprising 6.5% in the study group and 3.2% in the control group. Histologically, the epithelioid subtype was represented in 58% of the study group, whereas the biphasic subtype predominated (67.6%) in the control group. Only 7% of tumours were of the sarcomatoid subtype. The average age of patients in the study group was 57.4 years, thus lower than in the control group (62.8 years). Lung dust analysis showed an increased pulmonary asbestos burden in 94% of all patients; significant differences between the study and control group were not observed. In the majority of the total group pleural effusions were the first symptoms. Therapeutic data were available in fewer than 40% of all cases. Surgical interventions were performed, partly in combination with radiation and chemotherapy and as alternative treatments. Significant deviations in survival time dependent on therapy applied could not be proved. By multivariate analysis (Cox proportional hazards regression model) favourable prognostic factors for long-term survival were epithelioid tumour subtype, comparatively young age (<60 years), and female gender (P<0.05).