Association of CYP3A4/5, ABCB1 and ABCC2 polymorphisms and clinical outcomes of Thai breast cancer patients treated with tamoxifen

Figures & data

Table 1 Baseline characteristics of patients with and without recurrence (N = 30)

Characteristics	Recurrence (n = 10)		Nonrecurrence (n = 20)		P-valuea
Age at diagnosis, years
Mean (range)	48.30 (30–72)		48.45 (28–74)
Disease-free survival, years
Mean (standard deviation)	1.73 (0.74)		6.61 (1.73)
	Number	%	Number	%
Menstrual status					0.760
Premenopause	8	80	15	75
Postmenopause	2	20	5	25
Tumor size, cm					0.187
≤2	0	0	5	25
2.1–5	7	70	12	60
>5	3	30	3	15
Lymph node status					0.549
0	4	40	6	30
1–3	4	40	6	30
≥4	2	20	8	40
Tumor grading					0.985
1	1	10	3	15
2	6	60	11	55
3	1	10	2	10
Unknown	2	20	4	20
Lymphovascular invasion					0.948
Positive	2	20	6	30
Negative	3	30	9	45
Unknown	5	50	5	25
Estrogen receptor					0.333
Positive	9	90	20	100
Negative	1	10	0	0
Progesterone receptor					0.055
Positive	7	70	7	35
Negative	3	30	5	25
Unknown	0	0	8	40
HER2					0.184
Positive	1	10	0	0
Negative	7	70	11	55
Unknown	2	20	9	45
Radiation					0.196
Yes	3	30	9	45
No	7	70	11	55

Note:

a Fisher’s exact test.

Abbreviations: N, total number; n, group number; HER2, human epidermal growth factor receptor 2.

Table 2 Genotype and allele frequency of CYP3A5, ABCB1, and ABCC2

Genetic polymorphisms	Patients, n	Genotype frequency	Allele frequency
CYP3A5*3 6986 g>A
*1/*1	19	0.63	G = 0.80
*1/*3	10	0.33
*3/*3	1	0.04	A = 0.20
ABCB1 3435 C>T
CC	13	0.43	C = 0.67
CT	12	0.40
TT	5	0.17	T = 0.33
ABCC2*1C -24 C>T
*1/*1	17	0.57	C = 0.78
*1/*1C	13	0.43	T = 0.22
ABCC2 68231 A>G
AA	14	0.47	A = 0.73
AG	16	0.53	G = 0.27

Figure 1 Kaplan–Meier estimates of disease-free survival of patients with 3435 ABCB1 genotype.

Notes: (A) Analysis model 1 (CT compared with CC). (B) Analysis model 2 (CT compared with CC+CT).

Table 3 HRs in breast cancer patients treated with tamoxifen

ABCB1 genotype	HR	95% CI	P-value
(Analysis model 1)
CC	1.0 (ref)
CT	5.11	1.05–24.74	0.043
(Analysis model 2)
CC+TT	1.0 (ref)
CT	4.83	1.24–18.80	0.023

Abbreviations: CI, confidence interval; HR, hazard ratio.