Introduction: Chemotherapy is typically not given concurrently with whole brain radiation therapy (WBRT) for treatment of metastatic disease due to increased risk of myelosuppression and neurotoxicity. The goal of this study was to evaluate the prevalence, outcomes, and toxicities of concurrent delivery of systemic therapy with stereotactic radiosurgery (SRS) for treatment of brain metastases.
Methods: We conducted a retrospective review of 196 patients treated with at least one course of SRS without WBRT for brain metastases between 2009 and 2014. Outcome metrics included the administration of concurrent systemic therapy, grade of myelosuppression, development of neurological symptoms, and overall survival.
Results: 196 patients underwent a total of 290 SRS treatments, with a median of 2 lesions targeted per treatment. Histology included non-small cell lung cancer (40%), melanoma (18%), breast cancer (14%), and other (18%). 39% of SRS treatments were delivered concurrently with systemic therapy (i.e. systemic therapy started before or during SRS and continued through SRS), of which 51% were with conventional myelosuppressive chemotherapies, and 49% were with less-myelosuppressive targeted and hormonal agents. Common systemic agents included platinum chemotherapies (given with 35% of treatments), ipilimumab (17%), and taxanes (16%). Systemic therapy was given during the same week as SRS treatment in 79% of cases. Myelosuppression was minimal, with median grade 0 leukopenia, neutropenia, and thrombocytopenia, and grade 1 lymphopenia and anemia during the month following treatment. 52% of patients who received systemic therapy and SRS had neurological symptoms during the month following treatment, including fatigue (62%), headache (21%), weakness (15%), and gait instability (15%). Dexamethasone was used in 26% of cases in the month following treatment. Median overall survival for the cohort was 16.9 months following SRS.
Conclusions: Systemic therapy can be safely given concurrently with SRS for brain metastases, and this is an attractive option for patients who have both intracranial and extracranial disease. Our results suggest minimal myelosuppression and neurotoxicity with concurrent therapy.
Patient Care: Help guide treatment plans for patients with brain metastases and active systemic disease.
Learning Objectives: By the conclusion of this session, participants should be able to 1) describe the prevalence, outcomes, and toxicities of delivering systemic therapy concurrently with radiosurgery for brain metastases; 2) discuss, in small groups, management options for patients with active intracranial and extracranial metastatic disease.