VEGFA and neoplasm: We formed brain metastases by transplanting syngeneic mouse tumor cells via the internal carotid artery, elucidated the antitumor efficacy of the combined use of anti-PD-L1 and anti-VEGF antibodies on established brain metastases in immune-competent mice, and performed an examination of the immune cells within the brain metastases and the associated lymph nodes, as well as an assessment of the tumor blood vessel density.