Table 1

Histologic criteria employed in this study for the diagnosis of uterine smooth muscle tumors

Diagnosis

Tumor cell necrosis

Atypia

MF/10 HPF*

Leiomyosarcoma

Present

Diffuse moderate to severe

Any level

Present

None to mild

≥ 10

Absent

Diffuse moderate to severe

≥ 10

STUMP

Present

None to mild

< 10

Absent

Diffuse moderate to severe

5-9 or atypical mitotic figures

Absent

Focal moderate to severe

≥ 5

Atypical leiomyoma

Absent

Focal or diffuse moderate to severe

< 5

Leiomyoma

Absent

None to mild

< 5

*Mitotic figures per 10 High power field

Hewedi et al. Diagnostic Pathology 2012 7:1   doi:10.1186/1746-1596-7-1