Among women given a diagnosis of breast cancer, both overall and breast cancer–related mortality were significantly lower in the CEE arm (HR, 0.62 and 0.37, respectively).
Detection bias is unlikely
Although many observational studies have reported a modestly elevated risk of breast cancer in women who use estrogen therapy, their findings could reflect detection bias. That is, women who use any HT tend to have more contact with clinicians and, as a result, may undergo more screening mammograms than nonusers. In the WHI randomized trial, however, screening frequencies were similar among CEE and placebo users during and following the intervention phase.
What this EVIDENCE means for practice
These findings should reassure women who use estrogen to manage menopausal symptoms or prevent osteoporosis after hysterectomy that this therapy does not increase the risk of breast cancer.
The findings also underscore the importance of distinguishing between estrogen-only and estrogen-progestin therapy as we help our patients make sound decisions about HT.
NEW DATA SUPPORT THE PRACTICE OF OVARIAN CONSERVATION DURING BENIGN HYSTERECTOMY
Parker WH, Feskanich D, Broder MS, et al. Long-term mortality associated with oophorectomy compared with ovarian conservation in the Nurses’ Health Study. Obstet Gynecol. 2013;121(4):709–716.
Perera HK, Ananth CV, Richards CA, et al. Variation in ovarian conservation in women undergoing hysterectomy for benign indications. Obstet Gynecol. 2013;121(4):717–726.
In recent years, studies have documented the health risks of routine bilateral salpingo-oophorectomy (BSO) at the time of hysterectomy for benign indications. The body of evidence of the potential risks of BSO continues to expand, with publication, in April 2013, of two large analyses.
In the first analysis, investigators from the Nurses’ Health Study (NHS), a large prospective cohort, extended follow-up to 28 years. Among more than 30,000 participating nurses who underwent hysterectomy for benign indications, 16.8% of those who underwent BSO died during follow-up, compared with 13.3% of those with ovarian conservation (hazard ratio [HR], 1.13; 95% CI, 1.06–1.21).
BSO was associated with a lower risk of fatal ovarian cancer and, if performed before age 47.5 years, a lower risk of breast cancer as well. However, at all ages, BSO was associated with higher other cause-specific deaths (coronary artery disease, stroke, lung cancer, colorectal malignancy) as well as all-cause mortality. Similar increases in overall and breast cancer deaths were associated with BSO regardless of family history (sibling or mother) of breast or ovarian cancer.
Among women younger than age 50 who had never used estrogen therapy at the time of BSO, the surgery was associated with significantly increased all-cause mortality (HR, 1.41; 95% CI, 1.04–1.92). However, BSO before age 50 was not associated with significantly higher all-cause mortality in current or previous users of estrogen (HR, 1.05; 95% CI, 0.94–1.17).
Ovarian conservation is more common in younger women
In the second large analysis published this year, Perera and colleagues used records that include approximately 15% of all US hospital discharges to explore recent practices with respect to ovarian conservation at the time of hysterectomy for benign indications. They found that, among more than 750,000 women who underwent hysterectomy between 2000 and 2010, the ovaries were conserved in 53.6% of cases.
Ovarian conservation was more common in younger women, as it was practiced in 74.3% of cases involving women younger than age 40 and in 31% of cases involving women aged 60 to 64 years.
Ovarian conservation was also more common in recent hysterectomies than in surgeries performed more remotely in time.
It is heartening to observe that US gynecologists are practicing ovarian conservation more often at the time of hysterectomy for benign indications. The new analysis from the NHS supports this practice unless the patient has a mutation (BRCA, Lynch) that substantially increases her risk of ovarian cancer.
What this EVIDENCE means for practice
Unless contraindications apply, ObGyns should encourage women who undergo BSO before age 50 to use HT, at least until they reach the normal age of spontaneous menopause.
Clinicians who are considering performing elective BSO at the time of hysterectomy despite this guidance should recognize that in the aftermath of the WHI, and in the absence of contraindications,it may not be wise to perform BSO in women younger than age 50, since many women currently are reluctant to use estrogen therapy.
SWEDISH COHORT CONFIRMS THE ILL EFFECTS OF EARLY MENOPAUSE
Svejme O, Ahlborg HG, Nilsson JA, Karlsson MK. Early menopause and risk of osteoporosis, fracture and mortality: a 34-year prospective observational study in 390 women. BJOG. 2012;119(7):810–816.
Although early menopause has been linked to osteoporosis and fragility fractures, most studies documenting this association have been cross-sectional and retrospective, raising concerns about recall bias (inaccurate recall of when menopause occurred).