Current issues of ACP Journal Club are published in Annals of Internal Medicine


Etiology

HRT was not associated with increased breast cancer in women with a positive family history of breast cancer

ACP J Club. 1998 May-June;128:74. doi:10.7326/ACPJC-1998-128-3-074


Source Citation

Sellers TA, Mink PJ, Cerhan JR, et al. The role of hormone replacement therapy in the risk for breast cancer and total mortality in women with a family history of breast cancer. Ann Intern Med. 1997 Dec 1;127: 973-80.


Abstract

Objective

To determine whether hormone replacement therapy (HRT) is associated with an increased risk for breast cancer or all-cause mortality in postmenopausal women with a family history of breast cancer.

Design

A community-based cohort study (Iowa Women's Health Study).

Setting

Iowa, United States.

Participants

35 919 women 55 to 69 years of age in 1985 who had a valid Iowa driver's license. Exclusion criteria were premenopausal status, mastectomy, history of cancer other than skin cancer, or unknown family history of breast cancer.

Assessment of risk factors

Self-reported family history of breast cancer (mother, sister, or daughter) and HRT divided into categories: never used, ≤ 5 years, and > 5 years. Other risk factors were education, marital status, history of smoking and alcohol use, physical activity, reproductive history, medical history, menopausal status (natural, surgical, or other), height, weight currently and at 18 years of age, and waist and hip circumferences.

Main outcome measures

Breast cancer was ascertained using databases from Iowa, {adjacent states, the Mayo Clinic}*, and the National Institutes of Health. Deaths were taken from similar mortality databases.

Main results

12.2% of the cohort had a positive family history of breast cancer, and 38% reported HRT use. 1085 cases of breast cancer occurred during follow-up. After risk factor adjustment, the incidence of breast cancer did not show a difference between the groups who had, and did not have, a family history of breast cancer for any duration of HRT use. Decreased all-cause mortality was associated with former use of HRT for ≤ 5 years for women with no family history of breast cancer (relative risk [RR] 0.86, 95% CI 0.67 to 0.97) and women with a family history (RR 0.71, CI 0.51 to 0.98). Current use of HRT ≤ 5 years was also associated with decreased all-cause mortality for women with a family history of breast cancer (RR 0.24, CI 0.06 to 0.97). Women who had no family history of breast cancer and who had ever used HRT, compared with those who had never used HRT, had a decreased risk for mortality from coronary heart disease (RR 0.71, CI 0.57 to 0.89) but not for mortality from stroke, coronary vascular disease, breast cancer, any type of cancer, or other causes; women with a family history of breast cancer who had ever used HRT had no increase or decrease in risk for mortality from any of these causes.

Conclusions

In postmenopausal women with a family history of breast cancer, hormone replacement therapy was not associated with an increase in breast cancer. HRT was associated with a decreased risk for all-cause mortality.

Source of funding: U.S. National Cancer Institute.

For article reprint: Dr. T.A. Sellers, Division of Epidemiology, University of Minnesota, 1300 South Second Street, Suite 300, Minneapolis, MN 55454, USA. FAX 612-624-0315.

*Information supplied by authors.


Commentary

For peri- and postmenopausal women contemplating HRT, the choice is often complex and multifaceted. The benefits, including relief from menopausal symptoms and decreased risk for osteoporosis and cardiovascular and other diseases, need to be weighed against the possibility of increased risk for breast cancer, particularly in women with a positive family history. Any decision about HRT is a highly emotional ordeal.

Sellers and colleagues, along with others (1), provide reassuring evidence that, in the subset of postmenopausal women with a family history of breast cancer, HRT did not increase the risk for breast cancer. The authors found virtually overlapping rates of breast cancer in women with a positive family history, regardless of HRT use. The association also held despite short- or long-term HRT (≤ 5 or > 5 y) and whether HRT was used currently or in the past. The study concurs with several other reports, including the larger Nurses' Health Study (2).

This report is consistent with other studies suggesting that women using HRT seem to have decreased all-cause mortality, even in the subset of women with a positive family history of breast cancer (3). The study also lends credence to the hypothesis that potential increases in breast cancer detection among women who use HRT may be attributable to intensified screening.

This study offers useful information to the dialogue between women and their physicians about HRT.

Bruce E. Johnson, MD
University of Kansas Medical CenterKansas City, Kansas, USA

Bruce E. Johnson, MD
University of Kansas Medical Center
Kansas City, Kansas, USA


References

1. Colditz GA, Egan KM, Stampfer MJ. Hormone placement therapy and risk of breast cancer: results from epidemiologic studies. Am J Obstet Gynecol. 1993; 168:1473-80.

2. Stanford JL, Weiss NS, Voigt LF, et al. Combined estrogen and progestin hormone replacement therapy in relation to risk of breast cancer in middle-aged women. JAMA. 1995;274:137-42.

3. Henderson BE, Paganini-Hill A, Ross RK. Decreased mortality in users of estrogen replacement therapy. Arch Intern Med. 1991;151:75-8.