Table 2.
Risk of incident events (cancers) by oophorectomy status at time of hysterectomy
| Event | Age at Hysterectomy | ||||
|---|---|---|---|---|---|
| < 45 Years | 45-54 Years | ≥ 55 Years | All | ||
| Breast Cancer | Ovarian Conservation * | ||||
| Cases, N | 507 | 205 | 63 | 775 | |
| Incidence rate per 100,000 PY | 315 | 385 | 444 | 339 | |
| Both Ovaries Removed | |||||
| Cases, N | 292 | 520 | 83 | 895 | |
| Incidence rate per 100,000 PY | 222 | 363 | 445 | 305 | |
| Age-adjusted HR (95% CI) |
0.67
( 0.58, 0.78) |
0.94 ( 0.80, 1.11) |
1.04 ( 0.75, 1.44) |
0.84
( 0.76, 0.93) |
|
| Multivariate† HR (95% CI) |
0.62
( 0.53, 0.74) |
0.89 ( 0.75, 1.06) |
1.05 ( 0.71, 1.55) |
0.75
( 0.68, 0.84) |
|
|
Ovarian
Cancer |
Ovarian Conservation * | ||||
| Cases, N | 67 | 21 | 11 | 99 | |
| Incidence rate per 100,000 PY | 40 | 38 | 75 | 42 | |
| Both Ovaries Removed | |||||
| Cases, N | 2 | 2 | 1 | 5 | |
| Incidence rate per 100,000 PY | 1 | 1 | 5 | 2 | |
| Age-adjusted HR (95% CI) |
0.03
( 0.01, 0.14) |
0.04
(0.01, 0.16) |
0.07
( 0.01, 0.60) |
0.04
( 0.01, 0.09) |
|
| Lung Cancer | Ovarian Conservation * | ||||
| Cases, N | 118 | 39 | 13 | 170 | |
| Incidence rate per 100,000 PY | 71 | 71 | 89 | 72 | |
| Both Ovaries Removed | |||||
| Cases, N | 141 | 121 | 22 | 284 | |
| Incidence rate per 100,000 PY | 105 | 82 | 115 | 94 | |
| Age-adjusted § HR (95% CI) |
1.34
( 1.05, 1.72) |
1.21 ( 0.84, 1.74) |
1.54 ( 0.79, 2.99) |
1.17 ( 0.97, 1.42) |
|
| Multivariate‡ HR (95% CI) | 1.21 ( 0.91, 1.61) |
1.30 ( 0.87, 1.94) |
n/a** |
1.26
( 1.02, 1.56) |
|
|
Colorectal
Cancer |
Ovarian Conservation * | ||||
| Cases, N | 92 | 41 | 21 | 154 | |
| Incidence rate per 100,000 PY | 56 | 74 | 145 | 66 | |
| Both Ovaries Removed | |||||
| Cases, N | 96 | 113 | 25 | 234 | |
| Incidence rate per 100,000 PY | 72 | 77 | 131 | 78 | |
| Age-adjusted HR (95% CI) | 1.20 ( 0.90, 1.61) |
1.04 ( 0.73, 1.49) |
0.99 ( 0.56, 1.77) |
1.08 ( 0.88, 1.32) |
|
| Multivariate‡ HR (95% CI) | 1.36 ( 0.98, 1.89) |
1.16 ( 0.79, 1.72) |
1.11 ( 0.49, 2.51) |
1.23 ( 0.98, 1.54) |
|
| Total Cancer | Ovarian Conservation * | ||||
| Cases, N | 1121 | 439 | 156 | 1716 | |
| Incidence rate per 100,000 PY | 712 | 841 | 1128 | 768 | |
| Both Ovaries Removed | |||||
| Cases, N | 837 | 1147 | 199 | 2183 | |
| Incidence rate per 100,000 PY | 651 | 822 | 1089 | 762 | |
| Age-adjusted HR (95% CI) |
0.86
( 0.79, 0.95) |
0.99 ( 0.89, 1.10) |
1.02 ( 0.82, 1.26) |
0.92
( 0.86, 0.98) |
|
| Multivariate‡ HR (95% CI) |
0.83
( 0.75, 0.92) |
0.95 ( 0.85, 1.07) |
1.01 ( 0.79, 1.29) |
0.90
( 0.84, 0.96) |
|
PY= person-year; CI=confidence interval; HR=hazard ratio;
Reference group
Sample size is too small. No multivariate analysis was conducted.
Adjusted for age at hysterectomy, hypercholesterolemia, tubal ligation, family history of breast cancer, BMI in 1976, smoking status, use of estrogen therapy, duration of oral contraceptive use, parity, average daily alcohol consumption, and total hours of weekly physical activity.
Adjusted for age at hysterectomy, diabetes, high blood pressure, hypercholesterolemia, BMI in 1976, smoking status, use of estrogen therapy, duration of oral contraceptive use, parity, average daily alcohol consumption, total hours of weekly physical activity, and ASA use.
For lung cancer, risk estimates for all women were not encompassed by those within strata of age at hysterectomy due to confounding by age and age at hysterectomy and the high correlation between these variables.