Breast cancer is the leading cancer for woman in terms of incidence and mortality in the world. The objective of our study is the determination of the risk factors, in particular the hormonal factors on the appearance of this pathology. Our study included 305 newly diagnosed breast cancer patients at the Mohammed IV Center for the treatment of Casablanca. Data collection is done using a standardized survey, administered face-toface and completed from patient records. The statistical analysis of the epidemiological data was done using the R software. Our study population had a mean age of 50 years with a standard deviation of 11.35. More than half of the patients are married and most are housewives, living in urban areas. In our study population parity is on average of 3 and extremes ranging from 0 to 11 children. The average age at first pregnancy of our patients was 23.66 years and extremes ranging from 11 to 40 years. 96.41% of patients breastfed their children with an average cumulative duration of breastfeeding of 50.47 months. 56.1% of the patients were menopausal, the average age at menarche was 13.31 years and the average age of onset of menopause was 49.86 years. The medical history of the study population shows that only 60% of patients used oral contraceptives with an average duration of 8.43 ± 6.54 years. Invasive ductal carcinoma was the most common histologic type in our patients (77.7%) with SBR II grade in 68.3% of patients. Hormonal receptors are over expressed in 83.26% of cases, 29.9% of patients have HER2 positive and the triple negative represents only 13.22% of patients. All of our results converge on the association of several factors with breast cancer risk, such as, the low level of education and the increased use of oral contraceptives. However, further studies are needed to conclude that there is a close association between hormonal factors in Moroccan women and the risk of breast cancer.
