Ventriculoperitoneal Shunt for CNS Metastasis in Breast Cancer: Clinical Outcomes Based on Intrinsic Subtype

Abstract Background Leptomeningeal metastasis (LM) is associated with a grave prognosis in breast cancer (BC) and can be controlled with a ventriculoperitoneal shunt (VPS). Information regarding LM and VPS based on intrinsic subtype is limited; thus, we investigated the clinical outcomes of BC treated with VPS. Patients and Methods The present retrospective study comprised 70 patients diagnosed with LM who received a VPS. The patients were divided into four groups based on BC subtype: hormone receptor (HR)+HER2-, HR+/HER2+, HR-/HER2+, and triple negative BC (TNBC). Results The most common indications for VPS were uncontrolled intracranial pressure (57.1%) and uncontrolled headache (55.7%), which improved in 54/70 patients (77.1%) after VPS. Median overall survival after brain or leptomeningeal metastasis (OSCNS) and overall survival after VPS (OSVPS) were 7.6 and 2.3 months, respectively. Anti-HER2 treatment was a significant prognostic factor for better OSCNS based on multivariate analysis (hazard ratio (HR) 0.15, 95% CI 0.04–0.57, p=0.005), while TNBC was correlated with shorter OS after CNS metastasis (HR 2.82, 95% CI 1.46–5.48, p=0.002). Conclusions There were significant differences in clinical outcome based on intrinsic subtype of BC patients with LM who received a VPS. Anti-HER2 treatment in HER2+ patients was associated with better survival in MBC patients with VPS insertion compared to those without. Survival of metastatic BC (MBC) with VPS remained poor, especially in the TNBC subgroup.