Fine Structural Features of Neurosarcomas
In an electron microscopic study of an extensive series of malignant tumors of the soft tissues, sarcomas derived from elements of the peripheral nervous system were observed to possess unique morphologic features. Since these features were not seen in any of the other types of soft tissue sarcoma, they are useful as diagnostic criteria. They also provide insight into the histogenesis of neurosarcomas.By light microscopy, some neurosarcomas are seen to be composed of compactly grouped, spindle-shaped cells, and intercellular connective tissue is scanty. In other neurosarcomas, dendritic or stellate cells are loosely arranged in a relatively clear, occasionally myxoid-like stroma. The two types of tissue frequently coexist in the same neoplasm, and both are common in benign tumors of the peripheral nerves.Figure 1 shows part of a tumor cell from a neurosarcoma of the loosely-textured variety. The cytoplasm extends into a slender branching process containing longitudinally-oriented microtubules and fine filaments.