Table 1. Correlation among clinicopathologic status and the expression of ALDH1, PCNA and apoptosis.

characteristics	Subgroup	ALDH1			PCNA			AI
		≤20%	>20%	P	≤20%	>20%	P	No.	Mean±SD	P
Age	≤40 years	51	11	0.916	36	26	0.227	62	1.47±0.61	0.721
	>40 years	103	27		86	44		130	1.44±0.58
ER	Positive	113	26	0.541	92	47	0.242	53	1.41±0.60	0.578
	Negative	41	12		30	23		139	1.46±0.59
PR	Positive	96	22	0.668	77	41	0.359	118	1.48±0.57	0.540
	Negative	58	16		45	29		74	1.43±0.60
HER2	Positive	21	7	0.304	14	14	0.102	28	1.45±0.59	0.727
	Negative	133	31		108	56		164	1.41±0.59
Clinical Stage	II	114	6	<0.001	96	24	<0.001	120	1.50±0.52	0.116
	III	40	32		26	46		72	1.37±0.67
Grade	I	15	1	<0.001	13	3	0.145	16	1.39±0.52	0.834
	II	86	32		64	45		109	1.44±0.59
	III	14	53		45	22		67	1.48±0.61
Tumor size	T1	31	0	<0.001	31	0	<0.001	31	1.65±0.40	<0.001
	T2	102	15		82	35		117	1.51±0.55
	T3	21	23		9	35		44	1.14±0.70
Node Metastasis	1–3	131	23	<0.001	106	48	0.013	154	1.52±0.51	0.030
	≥4	22	14		16	22		38	1.35±0.67

ALDH1 = aldehyde dehydrogenase 1; AI = apoptotic index, percentage of apoptotic cancer cells.