Unequivocal identification of disseminated tumor cells in the bone marrow by combining immunological and genetic approaches–functional and prognostic information.

The detection and quantification of disseminated tumor cells (DTC) present in the bone marrow (BM), peripheral blood (PB) and apheresis products (AP) are becoming increasingly significant in the treatment of cancer patients. Three different applications are implemented in the clinical practice of pediatric and adult solid tumor patients: (1) the identification of tumor cells in the BM and PB at diagnosis; (2) the response of occult tumor cells to high-dose chemotherapy; and (3) the presence of tumor cells in the autograft. In solid tumors the clinical significance of DTCs at diagnosis or during the course of the disease, usually termed minimal residual disease (MRD) testing, is still under debate. These indistinct results are mainly due to methodical reasons. Therefore, a fully automated system (RCDetect/metafer) combining the detection of 'tumor-specific' immunological features together with 'tumor-typical' DNA aberrations has been developed allowing the unambiguous visualization of tumor cells in a hematopoietic surrounding.