The prognostic significance of disseminated tumor cells in bone marrow in patients with operable breast cancer: An updated analysis.

Abstract

e13013 Background: The main cause of death in breast cancer patients is the consequence of the spread and outgrowth of tumor cells at distant sites. The presence of disseminated tumor cells (DTCs) in the bone marrow at diagnosis is considered a predictor for metastasis. Methods: This is an updated analysis of a study in 102 patients with operable breast cancer on the significance of bone marrow micrometastases. The mean follow-up time is 127 months (range 10 - 142, median 129 months). Bone marrow aspirates were analysed for the presence of DTCs by a real time-polymerase chain reaction (RT-PCR) for cytokeratin 19 (CK) and mammaglobin (MAM).The aim of this study is to confirm the association between DTCs and disease-specific survival (DSS) as well as metastasis-free survival (MFS). Results: CK positivity was borderline significant for DSS (p = 0.054). MAM positivity was significantly prognostic for DSS with a hazard ratio (HR) of 3,110 (1,416-6,832) (p = 0,005). Patients positive for both CK and MAM did have a significant worse outcome with a HR for DSS of 7,329 (2,361 – 22,752) (p = 0,001). No significant influence on MFS was identified for CK (p = 0,658) or MAM positivity (p = 0,095). The combination of CK and MAM positivity did however confer a significantly increased risk for MFS (p = 0,043) at a HR of 4,126 (1,409-12,082). Conclusions: This study confirms the role of DTCs as a negative, prognostic factor in patients with operable breast cancer. The combination of CK and MAM is useful to identify this increased risk.