Brain metastasis reirradiation in patients with advanced breast cancer

The outcome of recurrent brain metastasis is dismal. This study aims to assess the clinical outcomes and toxicity of reirradiation as a salvage treatment for progressive brain metastasis in patients with advanced breast cancer. Between July 2005 and September 2014, the medical records of 56 patients with brain metastasis from breast cancer were retrospectively reviewed. Of these patients, 39 received whole-brain radiotherapy (WBRT) followed by stereotactic radiosurgery (SRS) reirradiation (Group 1), and 17 received SRS followed by WBRT reirradiation (Group 2). Overall survival (OS) and brain progression-free survival rates/times were calculated using the Kaplan-Meier method. Prognostic factors were evaluated using the Cox proportional hazards model. Change in neurologic function was also assessed. The median OS was 10.8 months (range, 1.3-56.8 months). In Group 1, the median PFS time (PFS-1) was 6.5 months and the OS time was 11.4 months. Multivariate analysis revealed that longer OS was significantly associated with a high Karnofsky performance score (KPS) (P = 0.004), controlled extracranial metastasis (P = 0.001) and a good response to reirradiation (P = 0.034). In Group 2, the median PFS time (PFS-2) after reirradiation was 8.5 months and the OS time was 10.8 months. Multivariate analysis revealed that longer OS was significantly associated with a high KPS (P = 0.018). The majority of the patients had improved or stable neurological function. Reirradiation is an effective and a safe treatment for patients with brain metastases from breast cancer. It might delay the progression of intracranial disease and improve neurological function. A suitable patient selection for reirradiation was suggested.