CEACAM5 and breast cancer: Blood tumor biomarkers such as Carcino-Embryonic Antigen (CEA) and Cancer Antigen 15-3 (CA15-3) are not recommended by American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO) and Italian Association of Medical Oncology (AIOM) guidelines in the follow-up of early BC patients [1,12,13], in asymptomatic patients.