For a patient with HER2+ breast cancer with progressive but asymptomatic disease in the brain, would you hold off on WBRT to do a trial of tucatinib, or proceed with WBRT then tucatinib?

The trial allowed both treated and untreated brain mets, and showed response rate and improved survival. If the patient is not a candidate for SRS, it’s reasonable to watch brain lesions with serial MRIs.