Breast cancer in black American women

Abstract

A case-control study of breast cancer among Black American women was conducted in seven hospitals in New York City from 1969 to 1975. Results are reported for 127 cases and 317 controls. Compared to women with a first birth before age 19, those with a first birth after 25 had a relative incidence rate for breast cancer of 3.8 and 2.2 for the pre- and postmenopausal age-groups, respectively. Compared to nulliparous women, parous women had a relative incidence rate of 0.6 for premenopausal and 0.7 for postmenopausal women. The incidence rate of breast cancer for women with a menopause after age 49 was estimated to be 3.1 times that of women with a menopause before age 45. Thus, the known risk factors for breast cancer among Whites are also related to the etiology of the disease among Blacks. The incidence rate of breast cancer has increased among younger Blacks since 1947 and is now similar to that among younger Whites. However, among older women, the incidence rate is still appreciably higher for Whites. The most likely explanation of this pattern is that Black women born since about 1925 are being exposed at the same frequency as White women to the causes of breast cancer.

A Prospective Study of Body Size and Breast Cancer in Black Women

“…13). Hospital-based case-control studies yielded conflicting results (10)(11)(12) + . Another possibility for the lack of association of obesity and weight gain with overall risk of postmenopausal breast cancer is that the strong and lasting effect of body size at age 18 years makes it difficult to detect an effect of weight gain and high BMI at later ages.…”

“…Several case-control studies have reported on the relation of obesity to breast cancer risk in African American women separately by menopausal status, with inconsistent results (10)(11)(12)(13)(14). There was little evidence of an association of current body mass index (BMI) with risk of breast cancer in premenopausal women (10)(11)(12)(13)(14).…”

“…There was little evidence of an association of current body mass index (BMI) with risk of breast cancer in premenopausal women (10)(11)(12)(13)(14). Among postmenopausal women, high BMI was associated with an increased risk (11,14), a reduced risk (12,13), or there was no association (10). In addition, the Cancer Prevention Study II (15) provided data on BMI and death from breast cancer during 20 years of followup, with a total of 257 breast cancer deaths among Black women; there was not a statistically significant association of BMI with risk of breast cancer mortality.…”

Associations between energy balance and body mass index and risk of breast carcinoma in women from diverse racial and ethnic backgrounds in the U.S.

“…Another hospital-based case-control study (in which cases were female African-American patients in seven New York hospitals and controls were female African-American noncancer patients) found no association between Quetelet's index (an index of weight corrected for height) and breast carcinoma risk; the means for this index were nearly identical for cases and controls. 15 A larger hospital-based case-control study of 528 African-American breast carcinoma patients and 589 African-American controls found an increased risk for breast carcinoma in postmenopausal women only, after multivariate adjustment (Table 1). 16 The Cancer and Steroid Hormone (CASH) case-control study included 490 African-American breast carcinoma cases and 485 controls ages 20 -54 years.…”

Reproductive factors and risk of breast carcinoma in a study of white and African‐American women

“…Until recently, the few existing studies of African-American women have been limited in sample size and design; the largest study included only 600 patients with breast carcinoma, and only 1 study used a population-based approach. [3][4][5] Although these studies suggest that parity and age at first full-term pregnancy have a similar effect on breast carcinoma risk for African-American and white women [3][4][5] and that the effects of lactation may differ between the two racial groups, 5 direct assessment of effect modification by race and age has been limited. However, a recent report 6 suggests that parity may increase breast carcinoma risk among young African-American women.…”