Table 2.

Summary of pathologic features in reported cases of PEComa NOS

Pathologic feature*	Non-Benign cases (n = 12)	Benign cases (n = 25)
Cytologic atypia	8/10 (80%)	9/25 (36%)
Necrosis	7/11 (64%)	4/18 (22%)
Lymphovascular invasion	4/8 (50%)	1/11 (9.1%)
Size (average diameters)	7.5 cm (n = 11)	4.54 cm (n = 24)
Significant mitotic activity (6 mitoses per 10 high power fields or greater	3/10 (30%)	0/24 (0%)

* For each histological feature, the denominator represents the number of cases in which the information assessed was available in the published reports. See text for caveats, exceptions and more detailed analysis