Fatores de risco do câncer de mama e sua associação com os subtipos moleculares em uma população do nordeste brasileiro

Abstract

Breast cancer (BC) is considered as a set of diseases that, at the molecular and cellular level, differ as a neoplasm of world disease and mortality between the world and Brazilian female population. In Brazil, it is estimated for the triennium 2020-2022, according to the National Cancer Institute (INCA), about 61.61 cases per 100,000 women, while in Paraíba there are 52.93 new cases per 100,000 women. The molecular classification characterizes the molecular subtypes of BC by the presence or absence of hormone receptors for estrogen (ER) and progesterone (PR), human epidermal growth factor (HER-2) and proliferative marker Ki-67. The present control study aimed to identify MC risk factors in a population of 313 cases and 321 controls and the differential association of risk factors with Triple Negative MC (TN) and other molecular subtypes. This is a study with an analytical approach and epidemiological evaluation carried out at the Hospital da Fundação Assistencial da Paraíba (FAP) in February 2020, December and March 2021, with data from users diagnosed with breast cancer and undergoing local treatment. A specific one was used for the evaluation of graphic, socioeconomic variables; family and clinical history, life habits and the practice of physical activity. A statistical analysis, using Fisher's exact test and Pearson's chi-square (χ2) to evaluate as categorical variables, and Wilcoxon's Nonparametric Student's T test on continuous variables. To quantify the associations between risk factors for BC, multinomial logistic regression analysis was applied. Control data served as a reference group. Results were presented as odds ratios (ORs), 95% confidence intervals (CIs) and p-values of likelihood ratio tests. Altogether, 145 (51.2%) of the 283 patients had advanced stage (III and IV) of the disease. Ki67 expression was detected on average in 60.80% of the triple negative (TN) tumor cells and 25 (61.0%) of them were grade III tumors (p<0.001; p<0.001). Cases had a more frequent family history of CM compared to controls (p < 0.001). Of all 313 cases and 321 controls, 91 (30.1%) and 68 (21.2%) were obese (p = 0.011). The cases most frequently reported consumption of alcohol, smoking and use of contraceptives (p <0.001; p = 0.008; p <0.001). Compared with the other molecular subtypes, NT cases were more often <40 and ≥60 years (p = 0.010). Age at menarche <12 years was found in 14 (32.6%) of 43 NT cases (p = 0.001). Obesity was more associated with the TN subtype, while the number of patients who reported alcohol consumption increased for the Luminal A subtype (p = 0.021; p = 0.009). The study identified an increased risk of BC in a study group of women from Northeast Brazil, who had a family history, were obese, consumed alcohol and used contraceptives. Furthermore, obesity was associated with an increased risk of TNBC among these women.