Table 1.

Criteria for subclassification of breast phyllodes tumors

Morphologic features	BP	BLP	MP
Circumscription	Well circumscribed	Intermediate	Infiltrative
Stromal pattern	Uniform	Heterogeneous	Overgrowth
Stromal cellularity	Moderate	Moderate	Marked
Stromal pleomorphism	Mild-moderate	Moderate	Marked
Stromal mitoses	Few (<5/10 HPF)	Intermediate (5-10/10 HPF)	Numerous (>10/10 HPF)

Note: Adapted from Rosen’s Breast Pathology [1]; WHO Classification of Tumours of the Breast [2]. Abbreviation: HPF, high-power field.