Introduction Early detection and diagnosis of breast cancer (BC) in important for subsequent treatment and prognosis. The aim of this study was to identify and sociodemographic differences in Brazilian BC patients.

Methods Data from 1651 female BC patients included in the Brazilian Cancer Institute's Hospital-Based Cancer Registry in 2007 were analysed using χ² test and Logistic Regression).

Results The average age was 57.3 (SD=13.9, range 19–98). Nearly 42.0% (n=689) from patients had localised BC, 46.5% (n=768) had locally advanced BC (LABC) and 11.8% (n=194) had metastatic BC. In a multivariated analysis, the LABC group had a number of significant findings. The odds of LABC for younger women (<40 years) were almost 60% higher (OR 1.57, 95% CI 1.03 to 2.40) than older women (≥70 years). The odds of LABC among illiterate women were 2.29 (95% CI 1.50 to 3.50) and 1.44 (95% CI 1.16 to 1.79) for women with <9 years of schooling compared to women with ≥9 years of schooling. No racial differences were observed.

Conclusion The lower education findings suggest that poor access to diagnosis may be involved in LABC, as well as cultural factors and lack of health literacy. Also, the young age of patients with LABC suggests that clinical and biological tumour characteristics and familial history of cancer in this group should be examined in further studies.