Table 1.

Definition of surrogate subtypes of luminal IBC according to 13th St. Gallen International Breast Cancer Conference (2013) Expert Panel and 5th edition of the WHO Classification of Tumors (2019) [16, 17]

	ER	PR	HER2	Ki-67
Luminal A like	Positive	Positive	Negative	Low
Luminal B like
HER2 negative	Positive	Negative or low and/or high Ki-67	Negative	High and/or PR negative or low
HER2 positive	Positive	Any	Overexpression and/or amplification	Any