Detection of disseminated tumor cells in the bone marrow and blood of breast cancer patients

Abstract

Early tumor cell dissemination can be detected in patients with breast cancer using immunocytochemical and molecular assays based on the use of monoclonal antibodies or PCR. Studies involving more than 4,000 breast cancer patients have demonstrated now that the presence of disseminated tumor cells (DTC) in bone marrow (BM) identified with immuncytochemical assays at primary diagnosis is a strong prognostic factor. The published studies for the detection of disseminated tumor cells in bone marrow fulfill the highest level of evidence as prognostic markers in primary breast cancer. In addition, various assays for the detection of circulating tumor cells in the peripheral blood have been recently developed and some studies suggest a potential clinical relevance of this parameter as prognostic and predictive factor. Advanced methods for molecular characterization of single tumor cells have been developed lately and this approach allows new insights into the metastatic cascade and characterization of targets for therapeutic approaches. These findings provide the basis for the implementation of DTC in BM or blood as markers for stratification and assessment of therapies in prospective clinical trials. The valuable information derived from these trials should help to improve future treatment of breast cancer patients.