First-line platinum and pemetrexed-treated patients with BAP1 loss had significantly longer median survival than those with retained BAP1 in both the Danish (20.1 versus 7.3 mo, p < 0.001) and Australian cohorts (19.6 versus 11.1 mo, p < 0.01)….BAP1 is a predictive biomarker for survival after first-line combination platinum and pemetrexed chemotherapy and a potential prognostic marker in PM.