Características epidemiológicas e clínicas de pacientes jovens com câncer de mama segundo o perfil mutacional

Abstract

Introduction: Breast cancer is the most common cancer in women and an important cause of death. Advanced age is directly proportional to the risk of developing the disease, but young women are more likely to develop breast cancer with worse clinicopathological charac teristics and more aggressive subtypes. It is essential to get to know the epidemiological pro file of young breast cancer (YBC) patients to better organize strategies to improve its control. Data from Brazilian YBC patients are scarce, especially regarding its association with a germline mutations with pathogenic potential. Objective: To compare epidemiological and clinical outcome data from non-mutated YBC patients to mutated ones. Material and meth ods: It is a cross-sectional retrospective study that included the analysis of medical records from two institutions in Minas Gerais/Brazil, focusing on YBC patients diagnosed between January 2012 to December 2020. The following variables were collected: sociodemographic profile of patients, tumor and patient-related characteristics, presence or absence of genetic mutation and variants of uncertain significance, follow-up time, and death. Binary logistic regression models were built to assess the association between traits and the occurrence of the mutation. This study was approved by the ethics committee of Hospital Felício Rocho before data collection began (4.553.583 / 2021). Results: 377 patients were included, 99.5% of them were women, mean age was 36 years, 63.7% were married at diagnosis, 62.5% with a com plete college education, and 89% had a private health insurance. Most of the sample (54.6%) underwent mastectomy, and 35.6% had sentinel lymph node involvement. Genetic testing was performed in 137 patients, and 29.9% of them presented a pathogenic or likely pathogenic mutation, predominantly in the BRCA1 gene (36.6%). Patients with a positive family history of cancer were more likely to be mutated (OR 1.92, IC 95% 0.90-4.16). Mutated patients un derwent more frequent mastectomies (OR 2.74, IC 95% 1.24-6.45) and contralateral prophy lactic surgery (OR 7.39, IC 95% 3.22-17.72). 36.3% of the tumors were luminal B and 43% stage II. Stage IV was scored in 6.7% of cases, locoregional recurrences in 11.9%, distant metastasis in 20.4%, and 10.9% deaths. 96,7% dos pacientes não mutantes e 100% dos mutantes estavam vivos em um acompanhamento médio de três anos (p 0,36). Conclusion: In this cohort of YBC has an un-favorable prognosis, with greater luminal subtype B, inter mediate histological grade, tumors larger than 2 cm with anatomical stage II, and 20,4% of patients, more than a fifth of the sample, progressing with distant metastases. We observed high rates of genetic mutation in this population and an increase in genetic testing over the years; patients with a genetic mutation with pathogenic potential were submitted more radical surgical procedures.