ABCG2 and brain disorder: A total of 19 patients had brain metastases when starting treatment with ABCP chemo-immunotherapy after TKI exhaustion, 8 (42%) had PDL1 < 1%, 7 (36.8%) had well-controlled CNS symptoms on dexamethasone and/or antiepileptic medication, and 15 (79%) had untreated brain disease.