We analyzed published tumor transcriptome data in conjunction with linked survival data to identify genes linked with breast cancer survival outcomes (1, 2). When comparing tumor transcriptomes based on 24-month survival, we discovered that the zinc-finger protein X-linked ZFX (3, 4) was among the most differentially expressed genes in both original and metastatic tumor tissues. ZFX expression was considerably enhanced in metastatic tumors of patients who survived more than 24 months, indicating that enhanced ZFX expression offers a survival advantage for patients with stage IV metastatic breast cancer.