Cytokeratin-positive cells in bone marrow in comparison with other prognostic factors in colon carcinoma

Abstract.

Background and aims: Despite the use of radical locoregional therapeutic methods and although conventional methods of diagnosis give no indication of metastases at the time of operation, distant metastases develop in approximately 50% of carcinoma patients within 5 years. While local relapses after the R0 resection of solid tumors are mainly a matter of concern for the surgeon, distant metastases can be traced back to the systemic dissemination of tumor cells at the time of operation. Patients/methods: A prospective study is presented in which 145 patients suffering from colon carcinoma were analyzed for the prognostic relevance of isolated disseminated tumor cells detected in the bone marrow (IDT BM). The patients were operated on between 1993 and 1997 and subsequently observed until 1999. Results: The monoclonal antibody A45-B/B3 was used with the immunocytochemical standard method for detecting IDT BM. For the purpose of cell cultivation, the cells were marked with the HEA-125 antibody and separated by means of magnetic cell sorting (MACS). Conclusion: In this investigation the presence of isolated disseminated tumor cells, as indicated by the A45-B/B3 antibody, proved to be an independent prognostic factor for survival time. The risk of an earlier death increased in node-negative and metastases-free patients with the detection of IDT BM by a factor of 12.60. The detection of IDT BM also represented an independent prognostic factor for the time until advancement of the tumor. The risk of an earlier relapse increased with the detection of disseminated tumor cells in the bone marrow containing the A45-B/B3 antibody by a factor of 18.02. A generally acknowledged standardization of the method is desirable. Due to the importance of the independent prognostic IDT BM factor, this method of ascertaining the pathological stage should be established at institutions of higher learning.