Breast feeding, parity and breast cancer subtypes in a Spanish cohort

Background

Differences in the incidence and outcome of breast cancer among Hispanic women compared with white women are well documented and are likely explained by ethnic differences in genetic composition, lifestyle, or environmental exposures.

Methodolgy/Principal Findings

A population-based study was conducted in Galicia, Spain. A total of 510 women diagnosed with operable invasive breast cancer between 1997 and 2010 participated in the study. Data on demographics, breast cancer risk factors, and clinico-pathological characteristics were collected. The different breast cancer tumor subtypes were compared on their clinico-pathological characteristics and risk factor profiles, particularly reproductive variables and breastfeeding. Among the 501 breast cancer patients (with known ER and PR receptors), 85% were ER+/PR+ and 15% were ER-&PR-. Among the 405 breast cancer with known ER, PR and HER2 status, 71% were ER+/PR+/HER2- (luminal A), 14% were ER+/PR+/HER2+ (luminal B), 10% were ER−/PR−/HER2- (triple negative breast cancer, TNBC), and 5% were ER−/PR−/HER2+ (non-luminal). A lifetime breastfeeding period equal to or longer than 7 months was less frequent in case patients with TNBC (OR = 0.25, 95% CI = 0.08–0.68) compared to luminal A breast cancers. Both a low (2 or fewer pregnancies) and a high (3–4 pregnancies) number of pregnancies combined with a long breastfeeding period were associated with reduced odds of TNBC compared with luminal A breast cancer, although the association seemed to be slightly more pronounced among women with a low number of pregnancies (OR = 0.09, 95% CI = 0.005–0.54).

Conclusions/Significance

In case-case analyses with the luminal A cases as the reference group, we observed a lower proportion of TNBC among women who breastfed 7 or more months. The combination of longer breastfeeding duration and lower parity seemed to further reduce the odds of having a TNBC compared to a luminal A breast cancer.     

Diagnosing breast carcinoma in young women.

OBJECTIVE--To assess the individual and combined diagnostic accuracy of clinical examination, mammography, and fine needle aspiration biopsy in young women with breast cancer. DESIGN--Analysis based on case notes of patients presenting with breast cancer during 1971-89. SETTING--A combined breast clinic. PATIENTS--Consecutive series of 81 women aged less than 36 with histologically proved breast cancer presenting with a discrete mass over 19 years. MAIN OUTCOME MEASURES--Results of clinical examination, xeromammography or conventional mammography, fine needle aspiration biopsy, and examination of tissue removed by surgery. RESULTS--The clinical diagnosis was correct in 47 women and radiography in 35. Fine needle aspiration biopsy was correct in 47 of the 63 women in whom it was successfully performed. Fine needle aspiration was significantly more accurate than mammography (78% v 45%, p less than 0.01). Ten (16%) patients had negative results on clinical examination, mammography, and fine needle aspiration. CONCLUSION--Mammography alone seems inadequately sensitive to detect breast cancer in young patients. When all investigations give negative results excision biopsy is the only way of obtaining a definitive diagnosis.     

Chronotype and postmenopausal breast cancer risk among women in the California Teachers Study

ABSTRACT

Chronotype is the behavioral manifestation of an individual’s underlying circadian rhythm, generally characterized by one’s propensity to sleep at a particular time during the 24 hour cycle. Evening chronotypes (“night owls”) generally suffer from worse physical and mental health compared to morning chronotypes (“morning larks”) – for reasons that have yet to be explained. One hypothesis is that evening chronotypes may be more susceptible to circadian disruption, a condition where the coordinated timing of biologic processes breaks down. The role of chronotype as an independent or modifying risk factor for cancer has not been widely explored. The objective of the current study was to evaluate the risk of breast cancer associated with chronotype in a case-control study nested within the California Teachers Study (CTS) cohort. The study population consisted of 39686 post-menopausal CTS participants who provided information on chronotype by completing a questionnaire in 2012–2013. 2719 cases of primary invasive breast cancer diagnosed from 1995/1996 through completion of the chronotype questionnaire were identified by linkage of the CTS to the California Cancer Registry. 36967 CTS participants who had remained cancer-free during this same time period served as controls. Chronotype was ascertained by responses to an abbreviated version of the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ) and was characterized into five categories: definite morning, more morning than evening, neither morning or evening, more evening than morning, definite evening. Multivariable unconditional logistic regression analyses were performed to estimate the odds ratios (ORs) and 95% confidence intervals (95% CIs) for each of the chronotypes, adjusted for established breast cancer risk factors. Compared to definite morning types, definite evening types had an increased risk of breast cancer with elevated ORs that were statistically significant in both the crude (OR = 1.24, 95% CI: 1.10–1.40) and fully-adjusted models (OR = 1.20, 95% CI: 1.06–1.35). The risk estimates in the fully-adjusted model for all other chronotypes did not significantly differ from one. These results suggest that evening chronotype may be an independent risk factor for breast cancer among a population of women who are not known to have engaged in any substantial night shift work. Further research in other populations of non-shift workers is warranted.     

Breast weight and hormone receptor status in women with breast cancer

Introduction

Aromatase activity in peripheral tissues including the breast is the main source of estrogen in postmenopausal women. There is evidence that local estrogen synthesis by breast aromatase contributes to mammary carcinogenesis. Therefore, we have postulated that high breast weight is associated with ER+ tumours.     

Prospective breast cancer risk factors prediction in Saudi women

Women's health is affected by breast cancer worldwide and Saudi Arabia (SA) is no exception. Malignancy has enormous consequences for social, psychological and public health. The aim of this study was to examine the risk factors for Saudi women from breast cancer using logistic regression models. In 135 patient cases for different stages of breast cancer was used to study case management, 270 healthy women from King Abd Alla Medical City, Mecca, SA were taken to predict the probability of women developing breast cancer, logistic regression was analyzed taking factors such as age, marital status, family history, parity, age at first full-term pregnancy, menopausal status, body mass index (BMI) and breast feeding. The logistic regression model showed that there are important risk factors (age, marital status, family history, parity, age at first full-term pregnancy, menopausal status, body mass index, and breast feeding) in development of breast cancer. Fewer cases were observed in unmarried women, age ≤30, BMI ≤20. In contrast, more cases were found with women age 41–50 married, BMI > 30, a smaller number of children, not breast feeding, age of first pregnancy ≥30, menopausal status age at 46–50. Based on our data there is role of risk factors in developing breast cancer, less BMI, the increase number of children, breast feeding, which are playing as protective factor for breast cancer.     

Endogenous oestrogens and breast cancer risk in premenopausal and postmenopausal women

Breast cancer risk is strongly related to several reproductive and hormonal factors, but the nature of the effects of endogenous oestrogens has been difficult to establish. Data are now available from several large prospective studies with biobanks of stored serum, enabling better characterization of the associations of endogenous oestrogens, and other endogenous hormones, with breast cancer risk. In postmenopausal women, relatively high serum concentrations of oestradiol are associated with a more than twofold increase in the risk for breast cancer, and this probably explains the increase in risk in obese postmenopausal women. In premenopausal women the data available on oestrogens are more limited and difficult to interpret due to the large variations in endogenous oestrogens during the menstrual cycle, but are compatible with a positive association between oestradiol and breast cancer risk. There is also evidence that breast cancer risk is positively associated with androgens, prolactin and insulin-like growth factor-I. Further data are required, with better assays and repeat measures, to provide more accurate estimates of risk and to clarify the role of oestrogens in premenopausal women and the roles of other endogenous hormones.     

Immunity to rubella in women of childbearing age in the United Kingdom.

In the first three years of a surveillance scheme for susceptibility to rubella in women aged 15-44 the results of over 1.3 million serological tests were collected by 80 laboratories throughout the United Kingdom. Seventy eight per cent of the results, or an average of 340,000 a year, were from pregnant women, so that just under half of all pregnant women in the United Kingdom were reported on. Eighteen per cent of results were from women tested before vaccination and the remainder were from diagnostic and other tests. Pregnant women showed an overall downward trend in susceptibility to rubella (from 4.2% at the beginning of 1984 to 3.0% at the end of 1986), and a similar decline was seen in the two other categories. Regional data showed a significant negative correlation between the proportion of pregnant women aged 15-19 who were susceptible to the virus and rate of uptake of vaccine in 14 year old schoolgirls. Women aged 25-29 were least susceptible. This form of laboratory surveillance is feasible and representative; it should be continued to monitor the effect of introducing the measles, mumps, and rubella vaccine.