CYP17 gene polymorphism in relation to breast cancer risk: a case-control study

Breast Cancer Research

Table 2 Descriptive characteristics of postmenopausal breast cancer cases and controls by CYP17 c.1-34T>C genotype

	CYP17 genotype
	A1/A1			A1/A2			A2/A2
Characteristic	Cases/controls^a	Cases	Controls	Cases/controls^a	Cases	Controls	Cases/controls^a	Cases	Controls
Genotype frequencies	550/488	36.7	36.5	711/638	47.4	47.7	238/212	15.9	15.8
Age (years)^b	550/488	63.3 ± 6.5	63.0 ± 6.5	711/638	63.4 ± 6.5	62.9 ± 6.4	238/212	62.8 ± 6.6	63.2 ± 6.1
Age at menarche (years)^b	492/441	13.5 ± 1.4	13.5 ± 1.4	650/579	13.6 ± 1.4	13.5 ± 1.4	221/202	13.2 ± 1.5	13.5 ± 1.3
Age at menopause (years)^b	546/483	49.9 ± 3.8	50.1 ± 4.1	705/631	50.7 ± 3.2	50.0 ± 3.8	238/212	50.6 ± 3.2	50.2 ± 4.2
Age at first birth (years)^b	470/447	25.4 ± 5.0	24.7 ± 4.6	604/575	25.1 ± 5.0	24.7 ± 4.7	198/192	25.6 ± 4.5	25.2 ± 4.9
Parity^b	550/488	1.9 ± 1.2	2.3 ± 1.4	711/638	1.8 ± 1.2	2.1 ± 1.2	238/212	1.8 ± 1.2	2.2 ± 1.3
Body mass index (kg/m²)^b	549/483	25.8 ± 4.1	25.8 ± 4.4	705/631	25.9 ± 4.2	25.2 ± 3.8	236/210	25.7 ± 4.4	25.3 ± 4.0
Duration of menopausal hormone use (years)^c
0	390/370	70.9	75.8	469/473	66.0	74.1	165/154	69.3	72.6
<4	59/50	10.7	10.3	96/74	13.5	11.6	26/25	10.9	11.8
≥4^d	101/68	18.4	13.9	146/91	20.5	14.3	47/33	19.8	15.6
Self-reported diabetes mellitus^c,d	550/488	8.73	8.20	711/638	9.42	7.21	238/212	8.82	8.49

^aIncluding only cases and controls with complete information on menopausal hormones and diabetes mellitus. ^bMeans ± standard deviation. ^cPercentages. ^dLong term users of menopausal hormones and women with diabetes mellitus were over-sampled.

ISSN: 1465-542X