In a patient with resected NSCLC whose only site of relapse is CNS (treated with WBRT or SBRT), would you also start systemic therapy with erlotinib/afatinib if the patient was found to be EGFR positive?

Would not do WBRT. if there are more than a dozen would treat with osimertinib as it crosses the BBB. If there were just a few and PET negative would trreat with SBRT and follow with ctDNA, brain MR and chest CT