Evaluation of known risk factors for breast cancer in Venezuelan patients with breast cancer, benign breast diseases, and without breast pathology

Abstract

1531 Background: Breast cancer (BC) represents the second cause of death from cancer in Venezuelan women, therefore, it is important to study the known risk factors for developing BC in Venezuelan patients. Also, little is known about the importance of these risk factors in patients with benign breast diseases (BBD). Due to this we carried out a prospective case-control study of known risk factors for developing BC in a group of female patients with BC and BBD with the purpose of defining clinical criteria which can be used to orient physicians and patients about the conducts to be followed not only by the patients, but also by their family group. Methods: We included 515 patients with BC, 507 with BBD, and 505 without breast pathology.The following risk factors were identified through a personal interview with each patient: family history of breast and ovary cancer, exposure to female hormones (exogenous and endogenous), and previous history of BBD. Results: The significant results when comparing the BC group with the BBD group were the following: strong family history of BC (p = 0.004), ingestion of oral contraceptives (p = 0.035), lactation (p = 0.00013), hormone replacement therapy (p = 0.000001), and previous history of BBD (p = 0.0000032). The significant results when comparing the BC group with the group without breast pathology were the following: family history of BC (p = 0.0000001), family history of ovary cancer (p = 0.0000001), nulliparity (p = 0.00009), age of first terminal pregnancy (p = 0.000001), number of abortion (p = 0.024), lactation (p = 0.03), and previous history of BBD (p = 0.0000001). A logistic regression model showed that the variables with the highest impact were lactation (p = 0.0001), family history of breast cancer (p = 0.0001), and family history of ovary cancer (p = 0.0001). Conclusions: Even though several hormonal factors were important, lactation and family history of breast and ovary cancer were the most important risk factors. No significant financial relationships to disclose.