Predicting the behavior of a uterine smooth muscle tumor can be made based on the histologic features of the lesion.
Criteria for evaluation:
(1) mitotic activity
(2) cellularity
(3) nuclear atypia
Mitotic Figures in 10 HPF |
Cellularity of Tumor |
Nuclear Atypia? |
Diagnosis |
0 - 4 |
normocellular |
No |
typical leiomyoma |
0 - 4 |
hypercellular |
No |
cellular leiomyoma |
0 - 4 |
variable |
Yes |
atypical leiomyoma |
5 - 15 |
normocellular |
No |
mitotically active leiomyoma |
>= 5 |
hypercellular |
Minimal |
leiomyoma of uncertain malignant potential |
>= 5 |
hypercellular |
Yes |
leiomyosarcoma |
patterned after Table 13.2, page 492 (Zaloudek, 1994)
Specialty: Hematology Oncology, Surgery, general, Obstetrics & Gynecology