Interestingly, the WHO grading system [4] showed a significant prognostic role in mesotheliomas with BAP1 loss (median survival 18.7 vs. 10.4 mo, p < 0.0001) but not in cases with retained BAP1 expression (8.9 vs. 6.2 mo, p = 0.061). Here, BAP1 is linked to mesothelioma.