Potential breast cancer risk factors among Saudi women aged 19-50 years in Jeddah: a case-control study.

BACKGROUND AND OBJECTIVES: The Saudi cancer registry reported in 2009 that the frequency of breast cancer is the highest among all types of cancer among Saudi women aged 30-59 years. The Makkah region had the second highest frequency of reported breast cancer cases, with patients having a median age of 46 years. The objectives of this study were to explore the distribution of selected known and hypothetically claimed breast cancer risk factors among Saudi women aged 19-50 years and describe the association of breast cancer with selected risk factors. DESIGN AND SETTING: An unmatched case-control study was conducted on breast cancer cases at three different hospitals in Jeddah. PATIENTS AND METHODS: Online OpenEpi was used and the method of Kelsey and colleagues was selected from OpenEpi output; the calculated number of cases and controls was 134 each. Women aged 19-50 years were included and the analysis was conducted on 151 cases and 166 controls as they met the age inclusion criteria. RESULTS: The mean age of patients was 40 years. A subgroup analysis for age at menarche less than 12 years showed an odds ratio (OR) of 1.4 6 [95% confidence interval (CI) 0.88-2.44]. A high proportion of cases reported the use of exogenous estrogen and progesterone (OR=4.7, 95% CI 1.7-13.0), previous mammography screening (89% of cases vs. 11% of controls), and affected family members (4.6 vs. 1.8, OR=2.64 [95% CI 0.67-10.4]. The OR for exercise frequency in the study group was 1.45 (95% CI 0.90-2.35). The OR for breastfeeding among mothers who breast-fed for more than 12 months was 0.56 (95% CI 0.35-0.88). CONCLUSION AND RECOMMENDATIONS: This study provides information on associative factors such as early age at menarche (<12 years), monthly income of at least 20 000 SR (5333 USD), use of exogenous estrogen and progesterone, previous biopsies/surgeries, previous clinical breast examination and mammography screening, and affected family members. Protective factors among premenopausal women, such as breastfeeding and exercising, have been described. Conducting comprehensive sessions on breastfeeding and physical education targeting young generations is highly recommended in order to reduce the risk for breast cancer among Saudi women aged 19-50 years.