Table 4.

Ovarian cancer risk factors and inflammatory exposures in relation to risk of TNF-α positive and TNF-α negative tumors.

	TNF-α negative cases		TNF-α positive cases
	n cases (%)	ORa (95% CI)	n cases (%)	ORa (95% CI)	p-heterogeneityb
Parity					0.02
0	6 (14)	1.00 (ref)	16 (44)	1.00 (ref)
1 or 2	20 (48)	1.09 (0.42, 2.83)	9 (25)	0.21 (0.09, 0.49)
3 or more	16 (38)	0.81 (0.29, 2.21)	11 (31)	0.31 (0.13, 0.73)
Oral contraceptive use (years)
0	22 (52)	1.00 (ref)	16 (44)	1.00 (ref)	n/a
<2	8 (19)	1.05 (0.54, 2.03)	7 (19)	1.05 (0.54, 2.03)
2-5	6 (14)	0.78 (0.39, 1.56)	8 (22)	0.78 (0.39, 1.56)
>5	6 (14)	0.33 (0.16, 0.68)	5 (14)	0.33 (0.16, 0.68)
Family history of breast or ovarian cancer	11 (26)	1.33 (0.75, 2.37)	7 (19)	1.33 (0.75, 2.37)	n/a
Endometriosis	3 (7)	0.76 (0.22, 2.57)	5 (14)	1.45 (0.53, 3.96)	0.40
Smoking					0.16
Never	20 (48)	1.00 (ref)	20 (56)	1.00 (ref)
Former	13 (31)	0.62 (0.30, 1.28)	13 (36)	0.75 (0.36, 1.58)
Current	9 (21)	2.79 (1.18, 6.62)	3 (8)	0.83 (0.23, 2.97)	0.06
BMI (kg/m2)					0.63
<25	21 (50)	1.00 (ref)	19 (53)	1.00 (ref)
≥25-30	12 (29)	0.80 (0.38, 1.68)	7 (19)	0.59 (0.24, 1.45)
>30	9 (21)	0.83 (0.37, 1.89)	10 (28)	1.17 (0.52, 2.63)
Genital powder use	13 (31)	0.94 (0.48, 1.87)	10 (28)	0.91 (0.43, 1.96)	0.95
Aspirin use	8 (19)	0.60 (0.26, 1.35)	9 (25)	1.14 (0.50, 2.62)	0.26
Ibuprofen use	11 (26)	0.92 (0.44, 1.92)	12 (33)	0.87 (0.41, 1.83)	0.92
Menstrual pain	17 (40)	1.60 (0.83, 3.08)	16 (44)	1.63 (0.81, 3.27)	0.97
Alcohol (g/day)					0.37
0-1.97	16(41)	1.00 (ref)	15(44)	1.00 (ref)
1.97-5.97	8(21)	1.06 (0.45, 2.53)	11(32)	1.60 (0.71, 3.58)
5.97-12.8	5(13)	0.69 (0.25, 1.92)	4(12)	0.51 (0.16, 1.57)
>12.8	10(26)	1.37 (0.61, 3.07)	4(12)	0.57 (0.18, 1.76)

Abbreviations: TNF-α=tumor necrosis factor alpha, IL-6=interleukin 6, BMI=body mass index

^aAdjusted for age, OC use, parity and family history or breast or ovarian cancer in the polytomous logistic regression model

^bp-value for heterogeneity was obtained using a likelihood ratio test