Abstract: Background and purpose: Breast cancer is a group of heterogeneous diseases which has racial disparities. Our study was to elucidate the clinicopathologic features of breast carcinoma in Shanghai Han and Xinjiang Uygur women and to analyze the racial differences. Methods: In this study, 125 cases of breast invasive ductal carcinoma of Shanghai Han women and 85 cases of Xinjiang Uygur women were collected. The clinical stage was analyzed. Histological grading was observed. Immunohistochemical staining of ER, PR, HER-2, CK5/6, CK14, EGFR, Ki-67 was performed. Molecular subtypes were studied. Results: The average age of onset of breast cancer in Xinjiang Uygur women was younger than in Shanghai Han women (P<0.05), and Xinjiang Uygur women were more likely to be diagnosed at less than 35 years old (P<0.01). The proportion of stageⅠwas higher in Shanghai Han women (20.0% vs 8.2%), while the proportion of stage Ⅲ was higher in Xinjiang Uygur women (50.6% vs 27.2%) (P<0.01). The proportion of grade 2 was higher in Shanghai Han women (67.2% vs 43.5%), while the proportion of grade 3 was higher in Xinjiang Uygur women (47.1% vs 31.2%) (P<0.01). The proportion of luminal A subtype was higher in Shanghai Han women (36.8% vs 18.3%), while the proportion of basal-like subtype was higher in Xinjiang Uygur women (29.6% vs 12.0%) (P<0.01). The molecular subtype was associated with race and histological grade (P<0.05). Conclusion: There are racial differences in clinicopathologic features of breast carcinoma between Shanghai Han and Xinjiang Uygur women.

Key words: Shanghai Han, Xinjiang Uygur, Breast cancer, Race, Clinicopathologic features, Molecular subtype