Pleural mesothelioma (PM) is a locally aggressive tumor associated with asbestos exposure. Despite legislative efforts to regulate asbestos use, its incidence continues to rise in some parts of the world. Chemotherapy and immunotherapy have improved survival in PM patients, but overall survival remains poor. Molecular analysis of PM patients has shown that most alterations occur in tumor suppressor genes, with BAP1 being the most frequently affected. Patients with germline BAP1 mutations have been reported to have a better prognosis, but this is not observed in those with somatic mutations. Interest in developing drugs targeting patients with BAP1 loss has led to several phase II studies in recent years. Unfortunately, initial results have not been very promising. In this review, we conclude that, at this time, with the contradictory results from studies and the limited number of patients evaluated, BAP1, the most commonly altered gene in PM, is not yet suitable for use in clinical practice as a prognostic or predictive factor. Future studies are needed to establish the prognostic or predictive value of BAP1.