Associação entre fatores de risco e subtipos moleculares do câncer de mama invasivo

Abstract

Background: Breast cancer is the type of cancer that most causes deaths among women in developing countries. In Brazil, an incidence of the disease increases and the number of new cases of breast cancer can be attributed to the increase in life expectation of women and changes related to reproductive factors and lifestyle. Objectives: The aim of this study was to analyze the literature on breast cancer risk factors and knowledge about the disease and to identify associations between risk factors and triple-negative breast cancer. Methods: Two scientific articles were developed for publication. The first article deals with an integrative review on the knowledge of breast cancer and its risk factors in Latin American studies. The second article deals with a cross-sectional study on lifestyle risk factors and triple-negative breast cancer, performed with 236 women diagnosed with invasive breast cancer in the state of Paraiba. Results: In the integrative review, of 47 studies selected, 27 were about risk of breast cancer and 20 were about knowledge or awareness. The main risk factors identified by the authors were obesity and overweight, old age, family history of breast cancer, nulliparity and menopause. The articles on knowledge focused in early diagnosis of breast cancer and breast self-examination was the most investigated method of detection. The cross - sectional study showed that smoking and obesity had associations with the triple- negative subtype of breast cancer. Women who smoked sometime in their lives had 3.70 (OR = 0.270, 95% CI: 0.10-0.68, p = 0.006) times less likely to have a triple-negative subtype. Patients with obesity had 3,514 (95% CI: 1.23 - 10.03; p = 0.019) more likely to have the triple-negative subtype when compared to the Luminal A subtype. Conclusions: The literature on breast cancer risk factors presents a better methodological outline and theoretical basis than the literature on the knowledge of the disease. Smoking is associated with lower chances of having triple-negative breast cancer, while obesity is associated with a higher chance of developing this type of breast cancer.