Age of Diagnosis Throughout the Years at Núcleo de Oncologia da Bahia

Abstract

INTRODUCTION: It has been suggested that there has been an increase in breast cancer incidence in young women in the last decade. The aim of this study is to verify if there was any change, in the past few decades, referring to the age of diagnosis of breast cancer patients at Nucleo de Oncologia da Bahia, located in Salvador, Bahia, Brazil. MATERIALS AND METHODS: This is a descriptive study that included 2612 patients diagnosed with breast cancer between the years 1974 and 2010 in a single private institution, specialized in the diagnosis and treatment of breast cancer. Data was collected retrospectively from medical records. The variables of interest were: a) socio-demographics: year of diagnosis, age at diagnosis and ethnicity; b) clinical: body mass index (BMI) (continuous variable), family history of breast cancer; c) tumor histology (ductal or others), size of the tumor (> or < 2 cm), presence or absence of positive lymph nodes at the time of diagnosis and presence or absence of metastasis at the time of diagnosis. All tests were two-tailed and results with p values 0. 05 were considered statistically significant. Data was analyzed using Statistical Package for Social Sciences software (version 17. 0, SPSS, Chicago IL, USA). Data was analyzed by an independent professional and a confidentiality agreement was established before access to the data. RESULTS: Regarding age at diagnosis, over the years, the average age was gradually increased. Each year, age increased 0. 279 (coefficient not standardized). This data was also positive for BMI at diagnosis and there was a negative relation regarding other variables: younger patients presented greater tumor size (standard error de 0. 605 with p < 0. 001), more positive lymph nodes (standard error 0.59 with p < 0. 001) and more often non-white ethnicity (standard error 0.55 with p < 0. 001). CONCLUSION: in spite of a tendency to believe in a recent increase of breast cancer incidence in younger women, this hypothesis was not confirmed in our population. Unlike, present belief there was an increase in median age of diagnosis. However, a relation can be established between younger patients and more aggressive tumors confirmed in literature data.