[The prognostic value of BAP1 protein loss in patients with malignant mesothelioma].

<b>Objective:</b> To explore the prognostic value of BRCA1-associated protein 1 (BAP1) expression loss in patients with malignant mesothelioma (MM) . <b>Methods:</b> A total of 82 MM patients from January 1998 to December 2017 in Zhejiang Province were selected to detect the expression of BAP1 protein by immunohistochemical analysis. Kaplan-Meier method was used to draw the survival curve, and multivariate Cox proportional risk model was used to analyze the factors affecting the survival rate. <b>Results:</b> Among 82 MM patients, 61 (74.4%) were female, aged (57±11) years. BAP1 protein expression was deficient in 39 patients (47.6%). The survival rate was correlated with the loss of BAP1 protein expression and age (χ(2)=5.27, 5.66, <i>P</i>=0.022, 0.017). Subgroup analysis showed that loss of BAP1 protein expression was associated with better prognosis in MM patients <57 years of age, female, pleural MM, epithelial MM, and treated with drugs or surgery (<i>P</i><0.05). Multivariate model results showed that positive expression of BAP1 protein (<i>HR</i>=3.75, 95%<i>CI</i>: 2.23-6.30, <i>P</i><0.001) and age ≥57 years (<i>HR</i>=1.66, 95% <i>CI</i>: 1.01-2.72, <i>P</i>=0.049) were risk factors for survival in patients with MM. <b>Conclusion:</b> Loss of BAP1 protein expression may be an independent prognostic factor in patients with MM, which is associated with longer survival.