ER (-\+) PR   (-\+) HER2  (-\+) Ki67* (-\+) Tumor Size ≤2 cm\ >2 cm
Caucasian American 222\967 392\806 942\164 257\447 768\394
African American 87/152 119\120 186\30 46\145 129\98
p(χ2) p(χ2)<0.001 p(χ2)<0.001 p(χ2)<0.7 p(χ2)<0.001 p(χ2)<0.25
*test for ER, PR, HER2 and Ki67 were not run on all tumour samples
Table 3: Cross-tabulation analysis of tumour pathology and patient characteristics stratified by ethnicity.