With regard to the malignant behavior of leiomyosarcoma, the most impoant criterion is
Option 4 is correct=the number of mitosis per high power field Leiomyosarcomas typically take the form of soft, hemorrhagic, necrotic masses. The diagnostic features of ove leiomyosarcoma include tumor necrosis, cytologic atypia, and mitotic activity. Robbins basic pathology 9th edition page no 694,heading=leiomyosarcomas..box=Morphology ref img
Blood vessel penetration by tumor cells
Tumor cells in lymphatic channels
Lymphocyte infiltration
The number of mitoses per high power field
Breast