Table 5.
Associations Between Estrogen Therapy (ET)-Only Use Among All Women and Estrogen Plus Progestin (EPT) Use among Women with Intact Uteri and Breast Cancer Risk by Tumor Characteristics, NIH-AARP Diet and Health Study Cohort
| ET-only Use Among All Women (number of cases, n=3657) |
Stage* |
Histology* |
Estrogen Receptor Status* |
Grade* |
||||||
|---|---|---|---|---|---|---|---|---|---|---|
| In Situ (n=607) | Invasive (n=3035) | Ductal (n=1968) | Lobular (n=334) | Mixed (n=238) | ER− (n=228) | ER+ (n=1175) | Grade 1 (n=590) | Grade 2 (n=1142) | Grade 3 (n=738) | |
| RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | |
| ET-only use | ||||||||||
| No | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) |
| Yes | 1.22 (0.95–1.57) | 1.13 (1.01–1.26) | 1.04 (0.91–1.20) | 1.20 (0.86–1.67) | 1.89 (1.24–2.89) | 1.02 (0.68–1.51) | 1.14 (0.94–1.38) | 1.42 (1.08–1.86) | 1.16 (0.97–1.39) | 0.98 (0.79–1.23) |
| Currency of use | ||||||||||
| Former | 1.11 (0.77–1.59) | 0.96 (0.82–1.13) | 0.92 (0.75–1.12) | 0.93 (0.56–1.53) | 1.19 (0.61–2.31) | 0.92 (0.51–1.66) | 1.09 (0.83–1.43) | 1.21 (0.82–1.80) | 0.85 (0.64–1.12) | 0.95 (0.69–1.31) |
| Current | 1.29 (0.98–1.70) | 1.22 (1.08–1.39) | 1.10 (0.94–1.28) | 1.39 (0.96–2.00) | 2.36 (1.49–3.75) | 1.08 (0.70–1.68) | 1.16 (0.94–1.44) | 1.50 (1.10–2.03) | 1.33 (1.09–1.62) | 1.02 (0.79–1.31) |
| Duration of use (y) | ||||||||||
| <5 | 1.22 (0.88–1.69) | 1.15 (0.99–1.32) | 1.13 (0.95–1.35) | 1.01 (0.64–1.59) | 1.90 (1.12–3.21) | 0.96 (0.56–1.64) | 1.26 (0.98–1.60) | 1.58 (1.12–2.21) | 1.24 (0.99–1.55) | 0.93 (0.69–1.25) |
| 5–9 | 1.07 (0.67–1.69) | 1.08 (0.88–1.32) | 0.99 (0.76–1.28) | 1.15 (0.62–2.11) | 1.92 (0.94–3.93) | 1.09 (0.55–2.14) | 1.18 (0.84–1.65) | 1.34 (0.81–2.22) | 0.86 (0.59–1.24) | 1.19 (0.82–1.75) |
| ≥10 | 1.32 (0.98–1.79) | 1.12 (0.98–1.29) | 0.96 (0.81–1.15) | 1.46 (0.98–2.19) | 1.87 (1.11–3.16) | 0.96 (0.58–1.58) | 1.05 (0.83–1.33) | 1.32 (0.94–1.86) | 1.16 (0.92–1.45) | 1.00 (0.75–1.33) |
| EPT Use Among Women with Intact Uteri (number of cases, n=2244) | Stage* |
Histology* |
Estrogen Receptor Status* |
Grade* |
||||||
| In Situ (n=349) | Invasive (n=1886) | Ductal (n=1218) | Lobular (n=213) | Mixed (n=155) | ER− (n=132) | ER+ (n=757) | Grade 1 (n=400) | Grade 2 (n=710) | Grade 3 (n=439) | |
| RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | RR† (95% CI) | |
| EPT use | ||||||||||
| No | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) | 1.00 (ref.) |
| Yes | 1.94 (1.51–2.48) | 1.81 (1.63–2.01) | 1.74 (1.53–1.99) | 1.60 (1.16–2.20) | 3.32 (2.25–4.90) | 1.11 (0.74–1.66) | 2.32 (1.96–2.76) | 3.51 (2.75–4.49) | 1.71 (1.44–2.04) | 1.48 (1.18–1.85) |
| Currency of use | ||||||||||
| Former | 1.39 (0.87–2.22) | 0.95 (0.75–1.20) | 0.93 (0.70–1.25) | 0.90 (0.45–1.79) | 1.07 (0.42–2.72) | 1.17 (0.58–2.38) | 1.07 (0.73–1.56) | 1.72 (1.06–2.79) | 0.66 (0.42–1.03) | 1.02 (0.65–1.59) |
| Current | 2.05 (1.59–2.65) | 2.02 (1.81–2.26) | 1.94 (1.69–2.22) | 1.77 (1.27–2.47) | 3.97 (2.67–5.91) | 1.05 (0.68–1.61) | 2.62 (2.20–3.13) | 3.93 (3.05–5.07) | 1.98 (1.66–2.37) | 1.61 (1.27–2.03) |
| Duration of use (y) | ||||||||||
| <5 y | 1.56 (1.13–2.16) | 1.34 (1.16–1.56) | 1.24 (1.03–1.49) | 1.45 (0.95–2.21) | 2.40 (1.45–3.96) | 1.02 (0.59–1.75) | 1.72 (1.37–2.16) | 2.52 (1.84–3.47) | 1.13 (0.88–1.45) | 1.29 (0.96–1.73) |
| 5–9 y | 2.31 (1.68–3.17) | 1.86 (1.60–2.16) | 1.77 (1.47–2.14) | 1.93 (1.26–2.96) | 3.20 (1.92–5.34) | 1.11 (0.62–1.97) | 2.25 (1.79–2.84) | 3.62 (2.64–4.97) | 1.75 (1.37–2.23) | 1.55 (1.13–2.13) |
| >10 y | 2.07 (1.46–2.93) | 2.48 (2.16–2.86) | 2.54 (2.13–3.02) | 1.37 (0.83–2.27) | 5.02 (3.13–8.06) | 1.19 (0.65–2.18) | 3.28 (2.65–4.06) | 4.86 (3.60–6.57) | 2.60 (2.08–3.25) | 1.70 (1.22–2.36) |
Cases with missing information on stage not shown (15 for ET, 9 for EPT). Histology, estrogen receptor status and grade restuls are limited to invasive cases only. Not shown are cases with other or missing histologies (495 for ET, 300 for EPT), borderline or missing estrogen receptor status (1632 for ET, 997 for EPT), and missing grade (565 for ET, 337 for EPT). The threshold for a postive hormone receptor status was >10 fmol of receptor per milligram of total protein.
RRs adjusted for age (continuous) and for race, age at first birth, menopausal status, number of breast biopsies, family history of breast cancer, and number of mammograms (per categorizations shown in Table 1). Models also include terms for other HT formulations.