There are currently five clinical trials in process to screen asymptomatic patients with advanced breast cancer for CNS involvement: NCT03881605 (metastatic TNBC/HER2-positive), NCT03617341 (metastatic/unresectable HER2-positive), NCT00398437 (Stage IV HER2-positive), NCT05115474 (all Stage IV breast cancer), NCT06247449 (TNBC/HER2-positive Stage II or III), and NCT04030507 (TNBC, HR-positive, HER2-positive, inflammatory breast cancer). This evidence concerns the gene ERBB2 and breast cancer.