Molecular subtyping of prostate cancer CTCs has yielded information relevant to patient prognoses, including the observation that presence of epidermal growth factor receptor (EGFR) expressing CTCs in castration-resistant prostate cancer patients treated with docetaxel correlates with shorter overall survival (5.5 vs. 20.0 months for patients with no EGFR+ CTCs, p < 0.001) [123]. Here, EGFR is linked to prostate cancer.