Persistent tumor cells in bone marrow of non-metastatic breast cancer patients after primary surgery are associated with inferior outcome

Table 4 Multivariate Cox regression analyses of systemic recurrence-free survival, and breast-cancer specific survival according to DTC detection in BM samples drawn at different time points from non-metastatic breast cancer patients

BM samples	DTC-positive patients	Systemic recurrence-free survival		Breast-cancer specific survival
BM samples	DTC-positive patients	Hazard ratio	P-values	Hazard ratio	P-values
BM1	16%	6.420	<0.001	7.081	<0.001
BM2	12%	5.793	<0.001	6.455	0.001
BM3	6%	6.841	0.004	4.888	0.022
BM2 and/or BM3	15%	5.397	<0.001	5.303	<0.001
BM1 and BM2/3	5%	7.188	<0.001	8.018	<0.001

BM1 drawn prior to surgery; BM2 drawn three weeks after surgery; BM3 drawn six months after surgery.
The different BM samples were included in the models in separate regression experiments. Only results from backward stepwise selection of variables are presented.

ISSN: 1471-2407