Is breast cancer in young Asian women more aggressive than in Caucasians? A cross-sectional analysis.

Ethnic differences in breast cancer are well described in studies comparing Hispanic and African-American populations to Caucasian populations. The aim of this study was to analyze the biological characteristics of breast cancer (BC) in the young Asian/Han Chinese population compared to Caucasians/Central Europeans. Histopathologies of 642 invasive BC in women at the age of 40 years and younger were analyzed in China and Austria. Pearson's chi-squared test was used to assess differences in the analyzed populations. Significantly larger BC >2 cm (p < 0.0001) and poorly differentiated BC (p = 0.02) as well as more triple-negative BC (p = 0.002) were identified among the Han Chinese group compared to the Central European group. This analysis will provide ethnic-specific insight into the biological characteristics of BC in young patients worldwide.