Evaluation of correlation between intrafractional residual setup errors and accumulation of delivered dose distributions in single isocenter volumetric modulated arc therapy for multiple brain metastases

•Accurate dose distribution is important for patient outcomes.•Intrafractional residual setup errors (RSEs) can affect dose distribution.•RSEs can lead to potential displacement of gross tumor volume (GTV) position.•Intrafractional RSEs in this study were low.•GTV D99.5% and D0.5% were not affected by distance of the GTV from the isocenter.