Table 2.

Clinical–pathologic characteristics of cases deemed “discordant” compared with “concordant” cases.

	Discordant (expected ≤ 25, actual > 25), n = 75	Concordant (expected ≤ 25, actual ≤ 25), n = 1443	p value
Age, mean	61 years	59 years	0.1352
Tumor size, mean	1.7 cm	1.8 cm	0.3404
Nottingham Grade
Grade I	18 (24%)	474 (33%)	0.1289
Grade II	56 (75%)	966 (67%)
Grade III	1 (1%)	3 (<1%)
PR status
Negative	20 (27%)	68 (5%)	<0.0001
Positive	55 (73%)	1375 (95%)
PR H-score mean	96	178	<0.0001
ER H-score mean	260	262	0.5945
Ki-67 index mean	16	14	0.0585
Nodal status
Negative	63 (84%)	1249 (87%)	0.8535
Positive	9 (12%)	171 (12%)
ITC	1 (1%)	5 (<1%)
Unknown	2 (3%)	18 (1%)

ER estrogen receptor, PR progesterone receptor, ITC isolated tumor cell.