Stratification of malignant pleural mesothelioma prognosis using recursive partitioning analysis

Prognostic factors and complicated prognostic models have been proposed for malignant pleural mesothelioma (MPM). This study was designed to stratify MPM prognosis by using a simple model.

Patients diagnosed with MPM in the past 10 years (n = 122) were examined retrospectively. Data on the presence of chest pain, performance status (PS), asbestos exposure, smoking status, white blood cell count (WBC), haemoglobin (Hb) concentration, platelet count (PLT), lactate dehydronate (LD), histology, stage, and date of death or censored status were collected. After the factors were examined in the univariate analysis, recursive partitioning analysis was performed.

Statistically significant factors related to survival were the type of histology, stage, PS, WBC, PLT, Hb concentration, and LD. Histology, stage, PS, and Hb concentration were used in multivariate analysis. Stage and Hb concentration showed good statistical significance, whereas PS was borderline significant. The survival analyses were stratified into five groups by PS, stage, Hb concentration, and chest pain using recursive partitioning analysis. Group A comprised patients showing the most favourable prognoses (PS 0-2 and Hb concentration >12.1 g dL(-1) or PS 0-2 and Hb concentration ≤12.1 g dL(-1) without pain), and group B comprised the remaining patients. The median overall survival in groups A and B was 563 days (95 % confidence interval [CI] 502-779) and 157 days (95 % CI 115-224), respectively (hazard ratio of 5.44 [3.46-8.53, P < 0.0001]).

The MPM patients with PS 0-2 and Hb concentration >12.1 or ≤12.1 g dL(-1) without chest pain had favourable prognoses.