Impact of cytochrome P450 2D6 polymorphisms on decision-making and clinical outcomes in adjuvant hormonal therapy for breast cancer

Table 3 Univariate correlation analyses of clinicopathological parameters with cytochrome P450 2D6 phenotype classification

	IM phenotype, n = 52	EM/UM phenotype, n = 18	P value
Median age in yr	62.5 (51-86)	61 (50-84)	0.574
Disease stage			0.595
I	24	6
II	17	8
III	11	4
Ethnicity			0.148
Chinese	47	13
Malay	3	3
Indian	1	2
Others	1	0
Comorbidities			0.728
Yes	43	14
No	9	4
Tumor histology			0.518
IDC	40	14
ILC	7	1
Others	5	3
Tumor grade			0.247
1	16	3
2	25	10
3	11	5
Median tumor size in mm	16.5 (1.2 to 70.0)	20.0 (3.0 to 45.0)	0.334
Lymphovascular invasion			0.527
Present	16	7
Absent	36	11
ER intensity			0.528
Low	2	0
Moderate	11	2
High	38	15
Negative	1	1
Proportion of tumor cells staining ER-positive			0.267
1% to 10%	4	0
11% to 49%	6	1
50% to 89%	14	3
More than 90%	27	14
PR intensity			0.631
Low	5	1
Moderate	9	5
High	31	11
Negative	7	1
Proportion of tumor cells staining PR-positive			0.785
1% to 10%	11	3
11% to 49%	8	2
50% to 89%	18	7
More than 90%	11	6
HER2 status			0.495
Positive	11	2
Negative	41	16
Clinical subtypes			0.692
ER+/HER2-	41	14
ER+/HER2+	10	2
ER-/HER2+	1	0

ER: Estrogen receptor; PR: Progesterone receptor; HER2: Human epidermal growth factor receptor-2; IDC: Invasive ductal carcinoma; ILC: Invasive lobular carcinoma; IM: Intermediate metabolizers; EM/UM: Extensive metabolizers/ultra metabolizers.