Table 3. Association of number of risk factors with breast cancer subtype using preoperative and postoperative Ki-67 levels in 171 patients with hormone receptor-positive and HER2-negative tumors.

Subtype	Number of risk factors			Total	P-value
	0 (N = 45)	1 (N = 82)	≥2 (N = 44)
Concordant	41 (91.1%)	57 (69.5%)	27 (61.4%)	125 (73.1%)	0.004
Discordant	4 (8.9%)	25 (30.5%)	17 (38.6%)	46 (26.9%)

HER2, human epidermal growth factor receptor 2