Table 2.

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

Phytoestrogen	All subjects			Japanese-American			White
Phytoestrogen	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)	0.40	1.21 (0.32-2.52)	1.46 (0.43-6.75)	0.35	0.54 (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)	0.84	0.22 (0.06-1.05)	0.34 (0.07-1.95)	0.35	0.06 (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)	0.72	0.003 (0.001-0.017)	0.003 (0.001-0.009)	0.49	0.006 (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)	0.72	1.44 (0.39-3.31)	1.92 (0.56-8.89)	0.64	0.93 (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)	0.84	1.81 (0.39-3.58)	2.17 (0.56-10.74)	0.64	0.93 (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)	0.50	1.00 (0.33-2.55)	1.13 (0.15-3.62)	0.25	2.36 (1.15-5.56)	2.85 (1.00-5.56)	0.42
Phytoestrogen	African-American			Latino			Native Hawaiian
Phytoestrogen	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)	0.24	0.26 (0.10-0.62)	0.38 (0.13-1.06)	0.56	1.20 (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)	0.03	0.04 (0.01-0.10)	0.05 (0.01-0.15)	0.56	0.19 (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)	0.24	0.004 (0.002-0.008)	0.005 (0.002-0.011)	0.15	0.005 (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)	0.10	0.37 (0.13-0.73)	0.47 (0.16-1.20)	0.56	1.50 (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)	0.10	0.37 (0.14-0.73)	0.48 (0.16-1.20)	0.56	1.50 (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)	0.81	1.21 (0.54-2.06)	1.84 (0.91-3.32)	0.15	0.91 (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.