Breast cancer prognosis in three different racial groups in relation to steroid hormone receptor status

Histopathology of breast cancer among African-American women

Although the overall incidence of breast cancer in African-American women is lower than in white women, African-American women younger than 50 years old have a higher incidence of breast cancer than white women. African-American women with breast cancer have a poorer survival rate than white women and are more likely to die of breast cancer in almost every age group. To explain this disparity, we studied a substantial body of literature that reported a biologic difference in the tumors found in African-American and white women. Specifically, more aggressive histopathologic patterns have been described among African-American patients with breast cancer when compared with white women. In addition, there are data that support an ethnicity-related variation in the expression of breast tumor hormonal markers. The objective of this study was to critically evaluate the existing published data on the histologic features of breast cancer to determine whether breast cancer in African-American women is a histologically more aggressive disease than in white women. We conclude that the aggressive tumor histology reported in African-American women has not been analyzed carefully with respect to the age of the patient at the time of diagnosis and the stage of disease at presentation. Furthermore, there is a need for central pathology review using accepted, published criteria for diagnosis of uncommon and controversial histologic subtypes of breast cancer.

Hormone receptors in breast cancer: racial differences in distribution and survival

The purpose of this study was to describe hormone receptor status and analyze the effect of receptors on survival from breast cancer. Comparisons were made between African-American and Caucasian racial categories. Breast cancer data from 1990 through 1997 collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program were analyzed. Subjects were 993 Caucasian men, 12,303 African-American women, and 141,045 Caucasian women. The number of African-American men was too small to analyze separately (n = 93). In addition to analysis of estrogen and progesterone receptor status by sex and race, tumor and patient characteristics included age, stage at time of diagnosis, and tumor histology. The proportion of Caucasian men with hormone receptor positive tumors remained relatively high and stable for all ages. In women, the proportion of hormone receptor positive tumors increased with age, with African-American women having the highest proportion of hormone receptor negative tumors. Caucasian men had highest proportions of hormone receptor positive tumors in all histology and stage groups, while African-American women had lowest proportions of hormone receptor positive tumors in all stage and histologic categories. Survival for African-American women was significantly worse for each hormone receptor category. In multivariate analyses, race was a significant independent predictor of survival, but sex was not. Although reasons for differences in hormone receptor status by sex and race are unknown, several hypotheses are discussed with respect to differences in tumor histopathology and risk factors.

Racial differences in breast carcinoma survival

BACKGROUND

Survival after breast carcinoma diagnosis is significantly worse among African American women for reasons unknown. The purpose of this study was to update reports on the National Surveillance, Epidemiology, and End Results Program and to examine the effect of race on breast carcinoma survival.

METHODS

Subjects were 135,424 women diagnosed with primary breast carcinoma between 1988-1995. Patient age, tumor stage at the time of diagnosis, hormone receptor status, tumor histology, menopausal status, and survival were compared by race category.

RESULTS

African American women diagnosed with breast carcinoma (n = 11,159) had a significantly increased risk of death from breast carcinoma and from all cancers compared with white women (n = 124,265), independent of the effects of other predictor variables. African American women were significantly younger at the time of diagnosis, with approximately 33% of the population age </= 50 years, compared with slightly <25% of the white women belonging to that younger age group. African American women were significantly more likely to present with advanced stages of breast carcinoma and, within each stage category, had significantly poorer survival compared with white women. African American women were significantly less likely to have tumors positive for estrogen or progesterone receptors, as well as histologically confirmed lobular and tubular carcinomas, whereas they were more likely to have inflammatory, medullary, and papillary histology compared with white women.

CONCLUSIONS

The results of the current study show that race is an independent predictor of survival from breast carcinoma. These findings are consistent with other large, population-based studies of racial differences in breast carcinoma survival and have been comported by studies of racial differences in the molecular biology of breast carcinoma, thus providing support for the epidemiologic credibility of the independence of the association.

Maternal pregnancy hormone levels in an area with a high incidence (Boston, USA) and in an area with a low incidence (Shanghai, China) of breast cancer

Characteristics probably associated with the fetal hormonal milieu have recently been shown to increase (birth size indicators, prematurity, neonatal jaundice) or decrease (pregnancy toxaemia) breast cancer risk in the female offspring. However, it is unknown whether differences in pregnancy hormone levels may contribute to the marked geographical variation in breast cancer incidence. We have compared, in a highly standardized manner, pregnancy hormone levels in a population with high incidence and one with low incidence of breast cancer. Three hundred and four pregnant Caucasian women in Boston and 334 pregnant Chinese women in Shanghai were enrolled from March 1994 to October 1995. Levels of oestradiol, oestriol, prolactin, progesterone, human growth hormone, albumin and sex hormone-binding globulin were measured in maternal blood at weeks 16 and 27 of gestation and compared between the two study sites using non-parametric Wilcoxon's rank-sum test. Demographical, anthropometrical and pregnancy characteristics were ascertained through interview, and relevant variables concerning delivery and the newborn were abstracted from medical records and paediatric charts. During the first visit, median serum levels of all studied hormones were statistically significant, and in most instances substantially, higher among Chinese women, who have a low incidence of breast cancer, compared with American women, who have a high incidence of breast cancer. An analogous pattern was evident during the second visit, although the relative differences tended to be smaller. Further research is needed to identify lifestyle or other exogenous determinants of pregnancy hormone levels, as well as possible mechanisms by which they may influence carcinogenic processes in the breast and possibly other organs.

Breast cancer in African American women: epidemiology and tumor biology

This review of published data on the epidemiology, pathology, and molecular biology of breast cancer in African American women seeks to identify how the etiology and presentation of the disease differ from those in white women. The crossover from higher to lower age-specific incidence rates in African American women at age 45 cannot be explained by current data on the distribution of risk factors. Data from six case-control studies suggest that the relative risks associated with both established and probable breast cancer risk factors are similar in African American and white women. Lower survival in African American compared to white women is primarily attributable to diagnosis at a later stage. However, evidence from a number of studies suggests that tumors in African American women may exhibit a more aggressive phenotype, which could also contribute to the survival disparity. Tumors in African American women are more likely to occur at a younger age, to be poorly differentiated and estrogen receptor negative, and to exhibit high grade nuclear atypia, more aggressive histology (more medullary and less lobular), and higher S-phase. Overexpression of p53 and erbB-2 occurs with similar frequency in African American and white women, although limited data suggest the former may exhibit different p53 mutation spectra. One study found high risk associated with a specific CYP1A1 polymorphism in African American but not white women. Additional studies of molecular differences in African American and white women are needed, with multifactorial assessment of the independent effects of molecular and conventional risk attributes.

Oestrogen and progesterone receptors in primary breast cancer: a population study

The results of a single centre study on cytoplasmic oestrogen (ER) and progesterone (PR) receptors and their combinations in primary breast cancer of 1957 patients from various parts of Croatia are presented. The frequency of ER+ tumours and tumour mean ER concentration were higher in patients over 50 years of age, while PR frequency and concentration were similar in patients over and under 50. The ER concentration was positively correlated with the age of patients, but the age-related increase in ER concentration appeared between 50 and 70 years of age. The pattern of receptor coexistence was age related. The frequency of ER+PR+ and ER+PR- increased and that of ER-PR+ and ER-PR- tumours decreased with the age of patients. The concentrations of ER and PR were higher in ER+PR+ than in ER+PR- or ER-PR+ tumours, respectively. When the patients were divided into groups under and over 50 years of age these differences appeared only in the latter group, while in the former the concentrations of ER were similar in ER+PR+ and in ER+PR- tumours, and the concentration of PR was higher in ER+PR+ than in ER-PR+ tumours. These data suggest a biological difference between breast cancers with various receptor combinations, as well as a difference in pathogenesis of the receptor negative and positive breast cancer.