This finding is noteworthy, as certain primary breast cancers (HER2-positive, ER/PR-positive, and TNBC) and lung cancers (ALK, ROS1, and EGFR mutations) with actionable mutations show strong intracranial response rates to targeted therapies.61,62 Consequently, ensuring access to targeted therapies for these primary cancers may extend to managing their associated CNS metastases, emphasizing the role of interdisciplinary collaboration in improving outcomes.63 This evidence concerns the gene ERBB2 and cancer.