How do you approach systemic treatment for isolated CNS recurrence of ER+/HER2+ disease, with local treatment completed, with prior treatment with chemotherapy + anti-HER2 agents?

This is always a difficult scenario with no clear guidance, and I think depends on a good discussion with the patient.

My preferred approach to this scenario is similar to an isolated CNS progression, in which we would not change systemic therapy if treated with local management. In this case, the p...

A similar approach as Dr. @Dr. First Last, but I also consider a period of treatment with oral agent with CNS benefit (i.e., lapatinib, neratinib, tucatinib/cape), and tailor the agent based on risk of systemic recurrence and comorbidities/toxicities.