Ethnic disparities in breast cancer between Central Europe Caucasian women of Slavic origin and Middle East Turkish subjects

Abstract

The biological, cultural, behavioral and sociodemographic differences across populations modulate breast cancer profile among races or ethnics. Following this, we aimed to identify differences in breast cancer epidemiology, histopathology, and clinical presentation from representatives of central Europe (Slovakia) and Middle-East countries (Turkey) to point on ethnic disparities in cancer biology. The population based cross-sectional study analyzing 414 cases of primary breast carcinomas where 214 represented Caucasian and 200 Turkish subjects. The differences were found for age at the time of diagnosis (<0.0001), education, menopausal status (<0.001), tumor localization (<0.01), size (<0.0001), grade (<0.05) and axillary lymph node status (<0.001) between groups. Although carcinomas in Slovak subjects were of higher grade, negative axillary nodal status was more frequent finding compared to Turkish patients (50.0 vs. 41.0%). The Slovak group showed carcinomas to be more often ER positive (72.4 vs. 54.0%; <0.001), ER/PgR positive (54.6 vs. 49.0%; <0.001), of better Nottingham prognostic index (<0.001), and less frequent Her-2 positive (21.2 vs. 28.5%). Slovak population expressed significantly higher risk of non-sentinel lymph node metastases with increased tumor size, grade, vascular invasion and Her-2 positivity compared to Turkey population. The tumor size >2 cm and high tumor grade (G3) bears a risk of OR=7.62 and OR=3.10 in Slovak compared to OR=3.94 and OR=1.79 in Turkish cases, respectively. There are wide demographic and biological disparities in breast cancer between observed ethnics providing unique information for clinicians working at the level of screening or therapy in these populations.