Occult metastases in patients with breast cancer

The presence of occult metastases in the lymph nodes, bone marrow, or both of these compartments may not only define patients who are at higher risk for recurrence and death but also may identify biologically distinct mechanisms of tumor spread (e.g., lymphatic vs. vascular dissemination). Use of techniques to detect occult metastases may also allow the identification of a biologically important population of cells, i.e., those cells constituting the earliest metastatic population of tumor cells. Thus, techniques that identify occult metastases may be valuable in furthering our understanding of the events regulating tumor dissemination.