Differential Gene Expression in Primary Breast Tumors Associated with Lymph Node Metastasis

Table 1

Clinical and pathological features of 76 invasive breast tumor specimens used in microarray analysis.

	Node negative; (𝑛=41)	Node positive; (𝑛=35)	P node− versus node+
Age
<50 years	37%	34%	NS
≥50 years	63%	66%
Histology
IDCA	95%	86%
ILCA	5%	9%	NS
Mixed	0%	5%
Grade
Well-differentiated	27%	9%
Moderately-differentiated	29%	43%	NS
Poorly-differentiated	44%	48%
Hormone receptor status^a
ER+/PR+	54%	51%
ER+/PR−	22%	12%	NS
ER−/PR−	24%	37%
HER2 Status
Positive	20%	26%	NS
Negative	80%	74%
Tumor Size
T1	63%	42%
T2	34%	54%	NS
T3	3%	4%

^aNo cases of ER−/PR+ were identified in this group of tumors.