Table 2.

Urinary excretion of phytoestrogens (nmoles/mg creatinine) among postmenopausal breast cancer cases and matched controls by race-ethnic group, Multiethnic Cohort Study

PhytoestrogenAll subjectsJapanese-AmericanWhite
Cases (n = 251)Controls (n = 462)P*Cases (n = 112)Controls (n = 216)P*Cases (n = 51)Controls (n = 96)P*
Daidzein
    Mean (±SD)2.50 (±6.02)3.86 (±8.25)3.36 (±7.69)5.60 (±9.34)2.24 (±5.07)2.86 (±7.77)
    Median (IQR)0.54 (0.18-2.05)0.66 (0.18-3.04)0.401.21 (0.32-2.52)1.46 (0.43-6.75)0.350.54 (0.13-2.12)0.31 (0.10-1.36)0.20
Genistein
    Mean (±SD)0.85 (±3.03)1.35 (±3.51)1.42 (±4.34)2.27 (±4.47)0.52 (±1.28)0.84 (±2.99)
    Median (IQR)0.10 (0.02-0.55)0.10 (0.02-0.73)0.840.22 (0.06-1.05)0.34 (0.07-1.95)0.350.06 (0.01-0.35)0.04 (0.01-0.32)0.20
Equol
    Mean (±SD)0.18 (±0.90)0.37 (±1.73)0.27 (±0.89)0.49 (±2.04)0.04 (±0.20)0.57 (±2.10)
    Median (IQR)0.004 (0.001-0.014)0.004 (0.001-0.012)0.720.003 (0.001-0.017)0.003 (0.001-0.009)0.490.006 (0.001-0.019)0.007 (0.002-0.023)0.42
Daidzein + genistein
    Mean (±SD)3.35 (±8.72)5.21 (±11.00)4.78 (±11.69)7.87 (±13.00)2.76 (±6.23)3.71 (±9.98)
    Median (IQR)0.71 (0.21-2.61)0.78 (0.22-3.97)0.721.44 (0.39-3.31)1.92 (0.56-8.89)0.640.93 (0.17-2.52)0.33 (0.11-1.65)0.20
Daidzein + genistein + equol
    Mean (±SD)3.53 (±8.88)5.58 (±11.41)5.05 (±11.83)8.35 (±13.31)2.81 (±6.25)4.27 (±11.00)
    Median (IQR)0.76 (0.21-2.71)0.81 (0.24-4.52)0.841.81 (0.39-3.58)2.17 (0.56-10.74)0.640.93 (0.17-2.64)0.34 (0.13-2.38)0.20
Enterolactone
    Mean (±SD)2.48 (±3.51)3.63 (±8.40)2.24 (±3.32)3.17 (±6.01)4.07 (±4.85)6.92 (±15.11)
    Median (IQR)1.32 (0.50-2.73)1.42 (0.33-3.71)0.501.00 (0.33-2.55)1.13 (0.15-3.62)0.252.36 (1.15-5.56)2.85 (1.00-5.56)0.42
PhytoestrogenAfrican-AmericanLatinoNative Hawaiian
Cases (n = 29)Controls (n = 45)P*Cases (n = 33)Controls (n = 54)P*Cases (n = 26)Controls (n = 51)P*
Daidzein
    Mean (±SD)0.60 (±1.53)1.12 (±2.53)1.05 (±3.19)1.56 (±4.27)3.22 (±4.67)3.19 (±9.20)
    Median (IQR)0.10 (0.05-0.36)0.37 (0.06-1.26)0.240.26 (0.10-0.62)0.38 (0.13-1.06)0.561.20 (0.27-3.64)0.34 (0.11-1.82)0.13
Genistein
    Mean (±SD)0.07 (±0.16)0.13 (±0.22)0.21 (±0.71)0.50 (±1.68)0.73 (±1.10)0.43 (±0.88)
    Median (IQR)0.01 (0.00-0.04)0.03 (0.01-0.16)0.030.04 (0.01-0.10)0.05 (0.01-0.15)0.560.19 (0.04-1.12)0.07 (0.03-0.29)0.13
Equol
    Mean (±SD)0.01 (±0.01)0.17 (±1.00)0.01 (±0.04)0.02 (±0.05)0.49 (±2.07)0.08 (±0.44)
    Median (IQR)0.003 (0.001-0.014)0.005 (0.002-0.013)0.240.004 (0.002-0.008)0.005 (0.002-0.011)0.150.005 (0.002-0.011)0.004 (0.001-0.011)0.58
Daidzein + genistein
    Mean (±SD)0.68 (±1.66)1.25 (±2.70)1.26 (±3.88)2.06 (±5.53)3.96 (±5.39)3.62 (±9.90)
    Median (IQR)0.10 (0.06-0.38)0.44 (0.08-1.58)0.100.37 (0.13-0.73)0.47 (0.16-1.20)0.561.50 (0.31-5.75)0.41 (0.17-2.54)0.05
Daidzein + genistein + equol
    Mean (±SD)0.69 (±1.66)1.42 (±3.02)1.28 (±3.88)2.07 (±5.53)4.45 (±6.28)3.69 (±9.92)
    Median (IQR)0.11 (0.07-0.39)0.45 (0.12-1.64)0.100.37 (0.14-0.73)0.48 (0.16-1.20)0.561.50 (0.32-5.78)0.45 (0.18-2.54)0.05
Enterolactone
    Mean (±SD)1.82 (±2.07)1.47 (±1.34)2.13 (±3.16)2.81 (±3.98)1.57 (±1.64)2.18 (±3.78)
    Median (IQR)1.35 (0.64-2.22)1.27 (0.36-1.90)0.811.21 (0.54-2.06)1.84 (0.91-3.32)0.150.91 (0.50-2.17)0.77 (0.15-2.42)0.94

NOTE: Cases and controls matched on geographic area, ethnicity, birth year, date and time of specimen collection, fasting status, and HRT use.

Abbreviations: IQR, interquartile range.

  • *P value for the difference between cases and controls based on the median test.