Objective. To investigate and compare aspects of breast cancer in young women (<40 years old) with older women (>40 years old). Methods. Retrospective, cross-sectional, analytical, and exploratory study based on data from 2009 to 2012 obtained from the Breast Cancer Information System (SISMAMA) and the Unified Health System Information Data (DATASUS). The studied population consisted of women (n=31.195) with malignant breast cancer. The analysed variables were education level, race, nodule detection at the clinical examination or image studies, presence of palpable axillary lymph nodes, surgical approach, and tumor histological type and grade. Results. There was increasing detection of breast cancer cases in young women among the studied years. Young women had more palpable lymph nodes (OR 1.28, 95% CI: 1.18–1.39), ductal carcinoma as the most frequent histologic type (OR 1.36, 95% CI: 1.22 to 1.53), and grades II and III tumor (OR 16.01 , 95% CI: 13.30 to 19.28 ). The lesion detection by clinical examination was higher in women <40 years (OR 1.34, 95% CI: 1.24 to 1.45). Conclusion. Although there are early detection measures related to breast cancer, they are not the usual practice of the young female public, suggesting the need for a review of existing public policies in the country.