Would you offer upfront osimertinib rather than whole brain irradiation for a patient with stage IV, EGFR exon 19 mutated lung adenocarcinoma who presents with leptomeningeal metastases?

As always a challenging situation is raised by a question in this forum. Clearly more clinical information is relevant. Not clear as to what "The patient 'presented' with leptomeningeal metastases" means.

In many patients, asymptomatic leptomeningeal metastases are detected on MRI scans of the brain...