Breast cancer mortality in black and in white women: a historical perspective by menopausal status

Coronary heart disease mortality for six ethnic groups in California, 1990–2000

PURPOSE

To investigate ethnic variations in coronary heart disease death in California, the authors examined total and CHD-specific mortality among non-Hispanic white (white), Hispanic, non-Hispanic black (black), Chinese, Japanese, and Asian Indian Americans. Deaths were identified in the California Mortality Database and population information was derived from the 1990 and 2000 censuses.

METHODS

Age-standardized death rates per 100,000 population were calculated for ages 25 to 84 years from 1990 to 2000. Proportional mortality ratios (PMRs) for each sex and age group were calculated by dividing the proportion of deaths due to CHD in each ethnic group by the proportion of deaths due to CHD in the total population.

RESULTS

Blacks had the highest all-cause age-standardized death rates among men (1614) and women (1014). Blacks had the highest CHD death rates among men (272) and women (190). PMRs for CHD were highest in Asian Indian men (161) and women (144), reflective of the higher percentage of CHD deaths compared with all cause deaths in this group. All sex-ethnic groups showed a decline in all cause and CHD mortality compared with the period between 1985 and 1990, except Asian Indian women, who experienced a 16% increase in all cause mortality and 5% increase in CHD mortality.

CONCLUSIONS

There is considerable heterogeneity in CHD mortality among ethnic subgroups, and additional research is needed to guide treatment and prevention efforts. Blacks and Asian Indians in California are identified as particularly high risk populations.

Existing data on breast cancer in African-American women: what we know and what we need to know

BACKGROUND

Much of what is known about breast cancer in African-American (AA) women is based on existing cancer surveillance data. Thus, it is important to consider the accuracy of these resources in describing the impact of breast cancer in AA populations.

METHODS

National cancer surveillance data bases are described, their most recent findings are presented, their limitations are outlined, and recommendations are made for improving their utility.

RESULTS

Breast cancer characteristics have been studied well in urban (but not in rural) and Southern AA populations. The recent Surveillance, Epidemiology, and End Results (SEER) Program expansion and the continued improvement of state cancer registry operations will provide opportunities to study larger and more diverse AA subpopulations. Recommendations for improving the utility of surveillance data bases include adding new items to better describe correlates of advanced stage at diagnosis and reduced survival of AA women with breast cancer by linking surveillance data bases with other large data bases to provide area-level socioeconomic status, health insurance status, and retrieving new information about patient comorbidities and biomarkers from medical records; improving the completeness and accuracy of treatment and survival information already collected for all patients; working to improve the dissemination of appropriate cancer data to nonresearch consumer communities, including clinicians, patients, advocates, politicians, and health officials; and the development of new training programs for cancer registrars and researchers.

CONCLUSIONS

The continued improvement of cancer surveillance systems should be considered important activities in this research agenda, because these data will play a far-reaching role in the prevention and control of breast cancer in AA women.

Strain differences in tamoxifen sensitivity of Sprague-Dawley and Fischer 344 rats

Why some women are at increased risk for the development of endometrial carcinoma while taking the antiestrogen tamoxifen (Tam) for breast cancer treatment or prevention is unknown. Various strains of rodents display differences in sensitivity to compounds with estrogenic activity, but whether differences in Tam sensitivity exist in rodent strains has not been investigated. In the present study, we investigated whether rat strain differences in reproductive tract sensitivity to Tam and estrogen exist between Fischer 344 (F344) and Sprague Dawley (SD) rats. Immature (21-23 day; 6/group), ovariectomized F344 and SD rats were treated with vehicle (control), 17beta-estradiol (E2) [1 x 10 (-6) to 1.0 micro g/kg body weight (BW)] or 4-OH tamoxifen (4-OHT) (1 x 10 (-4) to 10 mg/kg BW) for 2 days and then sacrificed on day 3. Reproductive tracts were collected, weighed, and examined for changes in histomorphology and expression of ER and nuclear receptor co-regulators (SRC1, p300, CARM1, GRIP1, SPA, REA and Uba3). Treatment with E (1 x 10(-5) micro g/kg BW) increased ( <0.05) uterine epithelial cell height in F344 but not SD rats, demonstrating increased sensitivity of the F344 strain to E. Conversely, treatment with 1 x 10(-3) mg/kg BW 4-OHT increased ( <0.05) uterine weight and epithelial cell height in SD but not F344 rats, demonstrating that the SD strain is more sensitive to the antiestrogen. Northern and Western blot and immunohistochemical analysis revealed that ER expression levels in the SD and F344 uterus were not different. Expression of receptor co-regulators was higher in the uterus compared to the vagina regardless of strain and higher CARM1 expression was seen in SD uterus compared to F344 rats. Understanding differences in Tam sensitivity may help us to better understand why some women develop endometrial cancer while taking Tam and be beneficial in treatment decisions for breast cancer patients.

Racial trends in age-specific breast cancer mortality rates in US women

OBJECTIVES

This study examined recent trends in age- and race-specific patterns of breast cancer mortality.

METHODS

We analyzed breast cancer mortality data for 1979 through 1996.

RESULTS

From 1993 to 1996, White women of all age groups experienced average annual decreases in breast cancer mortality. Throughout the study, young Black women had higher rates of breast cancer mortality than young White women. Older Black women had lower mortality rates than older White women in the earlier years of the study but experienced higher rates in the later years (1993-1996).

CONCLUSIONS

Trends in risk factors and early detection do not provide an adequate explanation for this recent substantial increase in breast cancer mortality among older Black women.

Trends in breast cancer mortality in Asturias, Spain

While breast cancer mortality rates are subsiding or beginning to decline in many western countries, in Spain they are increasing. We have studied breast cancer mortality rates in Asturias (Spain) by using the age-period-cohort model for the period of 1975-1994. There was an increase in the adjusted rates. The increase of relative risk of death in the period 1990-1994, in relation to that in 1975-1979, was 43%. There is a tendency for successive cohorts to have higher age-specific rates than previous cohorts. Trends in breast cancer mortality rates have been driven predominantly by birth cohort rate trends over the last decades in Asturias, suggesting that the changes in breast cancer mortality have been largely influenced by changes in aetiological factors.