1. A method for determining whether a patient has, or is likely to develop, invasive and metastatic breast cancer, the method comprising: using an antibody, or antigen binding fragment thereof, to detect IBC-1, or a fragment of IBC-1 that contains at least ten consecutive amino acids of IBC-1, in a test sample from a breast cancer patient, wherein detection of IBC-1, or the fragment of IBC-1, in the test sample in an amount higher than in a control sample indicates that the patient has, or is likely to develop, invasive and metastatic breast cancer.