Table I.

Differentiation between AMFB and AAM.

Characteristics	AMFB	AAM
Imaging findings	Well-circumscribed	Infiltrative tendency
	Strong heterogeneous enhancement	Enhanced in a whorled or swirling growth pattern
	Relatively small (≤5 cm)	Large (≥5 cm)
Pathological findings	Oval to spindle-shaped cells	Stellate to spindle-shaped cells
	Both hyper- and hypocellular areas are present	Sparse, homogeneous cell distribution
Clinical outcome	Recurrence is rare	Recurrence is frequent

AMFB, angiomyofibroblastoma; AAM, aggressive angiomyxoma.