Table 3.

Diagnostic Criteria for Benign and Malignant Splenic Lesions

		Benign Lesions	Malignant Lesions
B-mode US criteria	Echogenicity	50–70% hyperechoic	80–90% hypoechoic
	Echotexture	Homogeneous	Predominantly homogeneous
	Margin	Mainly well-defined	Almost well-defined, sometimes with irregular delineation
CEUS criteria	Hypoechoic pattern	No enhancement. (no enhancement in the arterial and parenchymal phase)	Mainly hypoenhancement (although the degree of enhancement in arterial phase was different, the enhancement in parenchymal phase was significantly lower than that in normal spleen)
		(b) Arterial hyperenhancement (partial or entire lesions showing iso-/hyperenhancement in the arterial phase, with slow and incomplete washout in the parenchymal phase)
		(c) Hypoenhancement (mainly found in hyperechoic lesions)
		(d) Delayed hyperenhancement (hypoenhancement in the arterial phase, with partial or entire iso-/hyperenhancement in the parenchymal phase)
	Degree of wash out	Slow (> 60 s after injection) and incomplete washout (residual microbubbles uptake > 180 s after injection)	Rapid (< 60 s after injection) and complete washout (no residual microbubble > 180 s after injection)
	Other characteristics	Sometimes wedge-shaped or round defect may be seen	Sometimes irregular intralesional vessels and/or non-perfused cystic areas may be seen