table 4.
Breast cancer risk by exposure to organic solvents and joint estrogen/progesterone status in breast cancer case-control study
| Status of the receptors | ER-/PR- | ER+/PR- | ER-/PR+ | ER+/ PR+ | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Exposure metrics | |||||||||||||
| n controls | n cases | ORa | 95%CI | n cases | ORa | 95%CI | n cases | ORa | 95%CI | n cases | ORa, | 95%CI | |
| Exposed to organic solvents | |||||||||||||
| Never | 2093 | 449 | 1.0 | 301 | 1.0 | 98 | 1.0 | 778 | 1.0 | ||||
| Ever | 409 | 120 | 1.40(1.1–1.8) | 71 | 1.27 (0.95–1.7 | 20 | 1.11 (0.7–1.8) | 137 | 0.97 (0.8–1.2 | ||||
| p - heterogeneity e | 0.56 | 0.40 | 0.008 | ||||||||||
| Duration of exposure (in yrs)b | |||||||||||||
| >0 – 5 | 124 | 37 | 1.45 (0.98–2.1 | 16 | 1.06 (0.6–1.8) | 7 | 1.22 (0.5–2.7) | 41 | 0.99 (0.7–1.4) | ||||
| >5 – 10 | 72 | 18 | 1.17 (0.7–2.0) | 17 | 1.71 (1.0–3.1) | 3 | 0.90 (0.3–2.9) | 29 | 1.14 (0.7–1.8) | ||||
| >10 | 213 | 65 | 1.46 (1.1–2.0) | 38 | 1.23 (0.8–1.8) | 10 | 1.14 (0.6–2.2) | 67 | 0.90 (0.7–1.2) | ||||
| p trend d | 0.82 | 0.76 | 0.63 | 0.65 | |||||||||
| p- heterogeneity of trends e | 0.91 | 0.58 | 0.58 | ||||||||||
| Crude intensity (quantity used in L/mo)b | |||||||||||||
| ≥1–10 | 313 | 95 | 1.43 (1.1–1.8) | 54 | 1.22 (0.9–1.7) | 17 | 1.20 (0.7–2.0) | 111 | 0.99 (0.8–1.3) | ||||
| >10 – 100 | 77 | 24 | 1.55 (0.96–2.5) | 15 | 1.58 (0.9–2.8) | 3 | 0.99 (0.3–3.2) | 25 | 1.04 (0.6–1.7) | ||||
| >100 | 19 | 1 | 0.31 (0.04–2.3) | 2 | 1.02 (0.2–4.5) | 0 | 1 | 0.21 (0.03–1.6) | |||||
| p trend d | 0.33 | 0.97 | 0.43 | 0.39 | |||||||||
| p- heterogeneity of trends e | 0.47 | 0.68 | 0.92 | ||||||||||
| Crude average frequency (hrs/wk)b | |||||||||||||
| ≥1 – <2 | 20 | 9 | 2.20 (0.98–4.9) | 5 | 1.70 (0.6–4.7) | 2 | 2.62(0.6–11.3) | 14 | 2.05 (1.0–4.2) | ||||
| ≥2 - ≤10 | 110 | 35 | 1.40 (0.9–2.1) | 15 | 0.79 (0.4–1.4) | 8 | 1.59 (0.7–3.4) | 49 | 1.06 (0.7–1.5) | ||||
| >10 – <20 | 185 | 46 | 1.23 (0.9–1.7) | 39 | 1.64 (1.1–2.4) | 6 | 0.74 (0.3–2.8) | 47 | 0.76 (0.5–1.1) | ||||
| ≥20 | 94 | 30 | 1.59 (1.0–2.5) | 12 | 1.23 (0.6–2.3) | 4 | 0.98 (0.3–2.8) | 27 | 1.00 (0.6–1.6) | ||||
| p trend d | 0.59 | 0.24 | 0.14 | 0.10 | |||||||||
| p- heterogeneity of trends e | 0.176 | 0.24 | 0.40 | ||||||||||
| Average latency (yrs)b | |||||||||||||
| 0 – 15 | 34 | 15 | 1.98 (1.0–3.7) | 4 | 1.39 (0.5–4.0) | 2 | 1.05 (0.2–4.5) | 16 | 1.40 (0.7–2.6) | ||||
| >15 | 375 | 105 | 1.35 (1.1–1.7) | 67 | 1.26 (0.9–1.7) | 18 | 1.13 (0.7–1.9) | 121 | 0.94 (0.7–1.2) | ||||
| p trend d | 0.26 | 0.94 | 0.39 | 0.19 | |||||||||
| p- heterogeneity of trends e | 0.49 | 0.73 | 0.91 | ||||||||||
| Cumulative exposure(hrs*L*yrs/wk*mo)b,c | |||||||||||||
| >0 – 39 | 206 | 61 | 1.42 (1.0–1.9) | 29 | 1.08 (0.7–1.6) | 9 | 0.95 (0.5–1.9) | 75 | 1.05 (0.8–1.4) | ||||
| >39 | 203 | 59 | 1.39 (1.0–1.9) | 42 | 1.44 (1.0–2.1) | 11 | 1.30 (0.7–2.5) | 62 | 0.88 (0.7–1.2) | ||||
| p trend d | 0.74 | 0.30 | 0.85 | 0.38 | |||||||||
| p- heterogeneity of trends e | 0.26 | 0.75 | 0.67 | ||||||||||
| Highest intensity*frequency(L*hrs/mo*wk)b,c | |||||||||||||
| level I | 298 | 92 | 1.46 (1.1–1.9) | 53 | 1.25 (0.9–1.7) | 12 | 0.90 (0.5–1.7) | 107 | 1.01 (0.8–1.3) | ||||
| level II | 111 | 28 | 1.25 (0.8–1.9) | 18 | 1.36 (0.8–2.3) | 8 | 1.77 (0.8–3.7) | 30 | 0.86 (0.6–1.3) | ||||
| p trend d | 0.51 | 0.95 | 0.23 | 0.67 | |||||||||
| p- heterogeneity of trends e | 0.61 | 0.15 | 0.84 | ||||||||||
| Crude average probabilityb | |||||||||||||
| ≥1 – <10% | 128 | 37 | 1.31 (0.9–1.9) | 22 | 1.23 (0.6–2.0) | 7 | 1.20 (0.5–2.7) | 47 | 1.06 (0.7–1.5) | ||||
| ≥10 – <50% | 134 | 39 | 1.40 (0.96–2.0) | 24 | 1.20 (0.8–1.9) | 5 | 0.86 (0.3–2.2) | 49 | 0.98 (0.7–1.4) | ||||
| ≥50 – <90% | 113 | 27 | 1.21 (0.8–1.9) | 23 | 1.60 (0.99–2.6) | 8 | 1.64 (0.8–3.5) | 31 | 0.83 (0.5–1.3) | ||||
| ≥90% | 34 | 17 | 2.44 (1.3–4.5) | 2 | 0.54 (0.1–2.3) | 0 | 10 | 0.99 (0.5–2.0) | |||||
| p trend d | 0.43 | 0.77 | 0.56 | 0.47 | |||||||||
| p- heterogeneity of trends e | 0.80 | 0.38 | 0.22 | ||||||||||
a
Adjusted for age, study site, education, BMI, age at menarche, menopausal status, age at menopause (in postmenopausal women), number of full term births, age at first full term birth, breastfeeding, and family history of breast cancer
b
Never exposed to organic solvents used as referent
c
For definitions see e-table I
d
p for trend in ever exposed to organic solvents
e
compared to ER-/PR- cases