Figure 2

The relationship between the Ki-67 indices and subtypes. The high expression (Ki-67 index≧14%) of the Ki-67 antigen was detected in 237 of the 363 breast cancers. The average Ki-67 index was 5.8% (±3.6 standard deviation) for the luminal A subtype, 24.3% (±9.8) for the luminal B (HER2-) subtype, 31.0% (±15.8) for the luminal B (HER2+) subtype, 43.0% (±19.6) for the HER2 subtype, and 46.4% (±23.1) for the basal-like subtype. The difference in the average Ki-67 index was statistically significant between the luminal A and other subtypes (P = 7.366×10^-12, P = 4.662×10^-12, P = 4.061×10^-10, and P = 7.779×10^-4 between luminal A subtype and luminal B (HER2- & HER2+), HER2, and basal-like subtypes, respectively).