The prognostic role of disseminated tumor cells detected in peripheral blood and bone marrow of colorectal cancer.

Abstract

Disseminated tumor cells (DTCs) have been associated with clinical outcome in various malignancies. The aim of this study is to examine the status of DTC in peripheral blood (PB) and bone marrow (BM) of colorectal cancer (CRC) and to evaluate its clinical significance. A total of 75 CRC patients treated with radical resection were enrolled in this study. Nested RT-PCR was used to detect the 2 representative markers of DTC, carcinoembryonic antigen (CEA) and survivin. The frequencies of DTC detected in PB and BM were 52.0% (39/75) and 29.3% (22/75) respectively, and showed no correlations with each other (p>0.05), their combination increased the sensitivity to 65.3% (49/75). Furthermore, DTC positive either in PB or BM was correlated with lymph metastasis, advanced stage and adverse 2-year progression free survival (PFS). In a multivariate analysis using the Cox proportional hazard model, DTC positive in PB and/ or BM was an independent unfavorable prognostic factor for CRC apart from lymph metastasis and adjuvant chemotherapy. CEA and/or survivin-positive DTCs may be a promising biomarker for prognosis assessment in CRC.