Hormonal risk factors for breast cancer in Morocco: case-control study

Drissi Houda, Imad Fatima Ezzahra, Bendahhou Karima, Benider Abdelatif, Radallah Driss


Background: The purpose of the study is to investigate hormonal risk factors and their impact on the development of this cancer.

Methods: This is a case-control study conducted at the Mohammed VI Centre for Cancer Treatment in Casablanca.

Results: The average age of the patients is 50.43 years with a standard deviation of 11.21. Exposure to endogenous estrogens appears to have an impact on the occurrence of breast cancer in the population. The early age of menarche in patients is on average 13.31±1.69 years compared to 13.65±1.54 years in controls, with a significant difference (p = 0.01). Parity is on average 2.54 children in cases versus 2.94 in controls with a significant difference (p = 0.02). Regarding the distribution of the cumulative duration of breastfeeding, 19.3% of patients compared to 12.3% of controls breastfed their children for less than one year; 80.7% of cases compared to 87.7% of controls breastfed their children for more than one year (OR=0.58; 95% CI: 0.35 - 0.97; P trend=0.03). In addition, hypovitaminosis D was noted in 2.3% of patients compared to 0.3% of controls with OR=7.14; 95% CI: 0.87 - 58.39; P trend=0.06. In addition, the supply of exogenous estrogen would also be incriminated. The risk of breast cancer appears to be influenced mainly by oral contraceptive use, which was found in 60% of cases vs. 41.3% of controls with OR=2.07; 95% CI: 1.50 - 2.86; P trend=0.0001.

Conclusions: The results highlighted that breast cancer risk is highly dependent on early and prolonged exposure to estrogenic impregnation. This effect would be modulated by ovarian activity, puberty or menopause age, parity and breastfeeding.


Breast cancer, Case-control study, Hormonal factors, Hypovitaminosis D, History of hormone therapy, Morocco

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