Subsequently, CEA-Scan has also been applied for detecting other CEA-positive cancers such as breast cancer, medullary thyroid cancer and lung cancer (Goldenberg, 1997; Goldenberg et al. 1997; Goldenberg and Nabi, 1999; Goldenberg and Wegener, 1997; Malamitsi et al. 2002; Sanidas et al. 2003). Here, CEACAM5 is linked to breast cancer.