This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breast, Subject name: Pathology
[{'content': 'With regard to the malignant behavior of leiomyosarcoma, the most impoant criterion is \nSelect and explain. \nA. Blood vessel penetration by tumor cells, B. Tumor cells in lymphatic channels, C. Lymphocyte infiltration, D. The number of mitoses per high power field', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 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', 'role': 'assistant'}]