Table 3.

The risk of breast cancer associated with CYP1B1*2 and GSTP1 Ile105Val stratified by EPT and ET use

GenotypeCase*Control*OR (95% CI)P
CYP1B1
    Never EPT users
        G/G317 (49.5)346 (51.0)1.0 (reference)
        G/T259 (40.5)291 (42.9)0.98 (0.78-1.23)
        T/T64 (6.9)42 (6.2)1.63 (1.07-2.48)0.14
    Ever EPT users
        G/G133 (56.8)105 (60.7)1.0 (reference)
        G/T81 (34.6)60 (34.7)1.07 (0.70-1.62)
        T/T20 (8.6)8 (4.6)1.90 (0.80-4.51)0.001
Pint = 0.96
    Never ET users
        G/G134 (49.3)155 (50.2)1.0 (reference)
        G/T113 (41.5)137 (44.3)0.98 (0.70-1.38)
        T/T25 (9.2)17 (5.5)1.69 (0.87-3.27)0.91
    Ever ET users§
        G/G179 (49.3)191 (51.6)1.0 (reference)
        G/T145 (39.9)154 (41.6)1.01 (0.74-1.38)
        T/T39 (10.7)25 (6.8)1.57 (0.91-2.72)0.23
Pint = 0.64
    Missing
14 (1.6)21 (2.4)
GSTP1
    Never EPT users
        A/A284 (43.8)284 (40.8)1.0 (reference)
        A/G293 (45.2)315 (45.2)0.94 (0.75-1.18)
        G/G71 (11.0)95 (13.6)0.73 (0.51-1.03)0.11
    Ever EPT users
        A/A97 (40.4)80 (45.4)1.0 (reference)
        A/G122 (50.8)72 (40.9)1.40 (0.92-2.11)
        G/G21 (8.8)24 (13.6)0.73 (0.38-1.41)0.97
Pint = 0.41
    Never ET users
        A/A125 (45.3)103 (32.8)1.0 (reference)
        A/G125 (45.3)166 (52.9)0.63 (0.44-0.90)
        G/G26 (9.4)45 (14.3)0.45 (0.26-0.78)0.001
    Ever ET users§
        A/A55 (59.8)37 (40.2)1.0 (reference)
        A/G77 (75.5)25 (24.5)1.30 (0.96-1.78)
        G/G12 (46.2)14 (53.8)0.97 (0.61-1.54)0.53
Pint = 0.004
    Missing
0 (0.0)3 (0.3)
  • * Some percentages do not sum to 100% due to rounding.

  • Adjusted for age and year of diagnosis (reference date for controls).

  • P value for test of trend.

  • § Limited to exclusive users of ET.