Another interesting aspect is the different trials proposed to assess the relevance of CTC detection and characterization as a “liquid biopsy” to test new treatment strategy using anti-HER2 drugs: the DETECT III trial uses a classical randomized phase III trial design and will answer in a large population whether or not lapatinib should be added in a HER2− breast cancer patients population that has been predefined before the start of the study: metastatic patients with any HER2+ CTC by immunocytofluorescence. Here, ERBB2 is linked to breast cancer.