Table 3.

Hazard ratios (HR) and 95% confidence intervals (CI) between low and high MEI among ER-positive breast cancers and risk of death in the Polish breast cancer study

	Person years	Alive	Dead	HR*	95%CI	P-value	HR**	95%CI	P-value
MEI
High	697.82	81	13	1.00			1.00
Low	375.49	35	17	2.59	1.22-5.49	0.01	2.85	1.25-6.47	0.01
Invasive grade
Well/moderately differentiated	927.94	102	25	1.00			1.00
Poorly differentiated	145.37	14	5	1.55	0.58-4.16	0.38	0.98	0.34-2.80	0.97
Tumor size, CM
0.1-2.0	582.56	63	17	1.00			1.00
2.1+	490.75	53	13	1.39	0.75-2.57	0.29	0.95	0.43-2.07	0.89
Nodal status
Negative	564.70	65	13	1.00			1.00
Positive	508.61	51	17	1.70	0.79-3.65	0.17	1.79	0.79-4.03	0.16
Hormone therapy- primary treatment
No	226.89	23	10	1.00			1.00
Yes	846.41	93	20	0.51	0.23-1.14	0.10	0.42	0.18-0.99	0.05
Radiation therapy -secondary treatment
No	771.11	86	18	1.00			1.00
Yes	302.20	30	12	2.66	1.34-5.30	0.005	2.93	1.34-6.41	0.01

^*Cox-proportional hazard ratios adjusting for age in 5-year intervals

^**Cox-proportional hazard ratios adjusting for age in 5-year intervals, tumor size, node status, grade, treatment regimen, and MEI