Existe-t-il encore des facteurs de risque de survenue d’un cancer du sein ?

Factors associated with gestational breast cancer: case-control study

The prevalence of gestational breast cancer (GBC) is 1:3,000-10,000 pregnancies. This study aims to identify the risk factors associated with GBC. This case-control study was conducted in the period between January 2004 and December 2014 at a reference maternity hospital for high-risk pregnancies in Rio de Janeiro. Two controls were selected for each case, totaling 21 GBC cases and 42 controls. Data were collected through a review of medical and hospitalization and delivery records. Reproductive, obstetrical, sociodemographic and health-related characteristics were investigated. Results: The mean age of pregnant women in both groups was 35.5 years. Menarche's mean age was also similar (12.3 years) in both groups. Mother's age at first pregnancy was > 30 years in 28.6% of the patients with GBC and in 2.4% of the control group (p = 0.03). Crude and adjusted odds ratio and their respective CI 95% were calculated through conditional logistic regression paired by mother's age. The results show that the risk for GBC increases 27% for each additional year of mother's age at first pregnancy (p < 0.02) and that mothers with lower schooling had higher risk of GBC (OR = 8.49). Conclusion: Our data confirm the association of primiparity over 30 years of age and low level of schooling with GBC.

Risk factors associated with a breast cancer in a population of Moroccan women whose age is less than 40 years: a case control study

INTRODUCTION

Breast cancer is the most common cancer in morocco women were it occupies the first place in term of incidence and mortality. The aim of the present paper is to evaluate the risk factors associated with a breast cancer in a population of Moroccan women.

METHODS

A case-control study was conducted with population women whose age is less than 40 years during 2008-2010 at the National Institute of Oncology of Rabat. These women were interviewed for Epidemiological information and risk factor for breast cancer.

RESULTS

Included in this study were 124 cases and 148 age matched controls. No statistically significant case-control difference was found for the early age of menarche (OR = 2.474; CI 95%: 1.354- 4.521), and family antecedents of first degree of breast cancer (OR = 11.556; 95% CI: 2.548-52.411). However physical activity (OR = 0.507; 95% CI: 0.339 -0.757) early maternity age (OR = 0.212; 95% CI: 0.087 - 0.514), multiparity (OR = 0.742; 95% CI: 0.359 -1.539) and breastfeeding than 6 months (OR = 0.739; 95% CI: 0.357 -1.523) appear as significant protective factors.

CONCLUSION

This study show the criminalization of only part of the known risk factors of breast cancer in this age group and confirms the probable protective role of physical activity and factors related to life reproductive women in our study (early childbearing, multiparity and lactation).

[Night work, shift work: Breast cancer risk factor?]

OBJECTIVE

The aim of this review was to determine the link between night/shift work and breast cancer.

METHODS

The analysed articles were taken from the PUBMED database between 1996 and 2015. The keywords used were "breast cancer risk", "night work" and "shift work". In total, 25 articles were selected.

RESULTS

Night/shift workers are more at risk to develop a breast cancer (relative risk (RR) between 1.09; 95% CI: 1.02-1.20 and 1.48; 95% CI: 1.36-1.61 in the meta-analyses). However, this risk is not found by some cohort and case-control studies. The circadian rhythm disruption, responsible of disorderliness of melatonin secretion, could be one of the mechanisms involved in the increase of that risk. Hormonal status of night/shift workers, their geographic origin, their lifestyle and their vitamin D deficiency appear as other mechanisms potentially responsible for increased risk of cancer in this professional population. Moreover, a dose-effect connection may exist, with an increase of the risk with the number of years of night/shift work.

CONCLUSION

Night/shift work is associated with a moderate increased risk of breast cancer, especially among women who worked over 20 years. Recommendations concerning the breast monitoring in this population could be diffused. The benefit of melatonin supplementation remains to be assessed.

[Vitamin D and breast cancer: is there a link?]

OBJECTIVE

The aim of this review is to know the relationship between breast cancer and vitamin D, synthesised by skin or brought by food or supplementation.

MATERIAL AND METHODS

The selected articles were extracted from the Pubmed database between 1998 and 2012. The keywords used were: "25-hydroxyvitamin D", "breast cancer recurrence", "breast cancer risk", "serum levels of vitamin D", "vitamin D intake". A total of 37 articles were selected.

RESULTS

The sun exposure, via the skin vitamin D synthesis, is associated with a decreased risk of breast cancer. This decrease seems also likely for food contributions and an over 400IU per day vitamin D supplementation. An inverse relationship between plasma 25-hydroxyvitamin D (25-OH-D) level and breast cancer risk has been suggested. An increased 25-OH-D level seems associated with a decreased risk of breast cancer recurrence.

CONCLUSION

Recommendations concerning a vitamin D supplementation could be established, but should be supported by additional studies.