|
 |
|
|
|
|
|
|
|
|
MDM SITE
General Index
|
|
|
|
NOTE:The reader has not reached the end of the frame for this chapter until he encounters a horizonally, rather than vertically, oriented navigation bar.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
Fig. c2t3D3: In adventitial myxofibroblastoma, various cell forms are represented. Some of the cells have the cytologic, and immunohistochemical characteristics of dendritic histiocytes (i.e., the dendritic cell to the left). The other cells of the tumor are rounded (epithelioid), stellate, or spindle shaped. A variation of the epithelioid cell has a pale, mucinous and spidery cytoplasm; some of the muciparous cells are mutlinucleated. Some observers would characterize all of the cells as derivatives of the dendritic histiocytes.
|
|
|
 |
|
|
|
Fig. c2t3D4: Histiocytes of the dermis include the KP-1 positive cell, the phagocyte; the dendritic cell of the vascular mesenchyme and the reticular dermis, the factor XIIIa + dendritic cell; and the dendritic cell of the papillary dermis and epidermis, the S-100 positive cell, including the Langerhans cell. In the common approach to fibrous histiocytoma, the histiocyte would function as a fibroblast.
|
|
|
 |
|
|
|
Fig. c2t3D5: To the right of the broken line in this drawing, a sequence in which a small blast cell has the capacity to differentiate as either a dendritic cell or a fibroblast is depicted. To the left in a different sequence, the dendritic histiocyte and the fibroblast are interdependent; the actions of the factor XIIIa + histiocyte influences the functions of the fibroblasts, and impact on the mucinous or fibrous nature of the dermis, particularly the reticular dermis.
|
|
|
 |
|
|
|
Fig. c2t3D6: Of the dermal populations of dendritic cells, the factor XIIIa + cell influences the quality of the fibrous matrix of the dermis. The S-100 + cell has a less defined role in regard to having an influence on the quality of the reticular dermis.
|
|
|
 |
|
|
|
Fig. c2t3D7: The tumor cells of adventitial myxofibroblastoma are rounded, stellate, or spindle shaped. There is a tendency for the rounded (epithelioid) cells to cluster in a mucinous matrix that is fiber poor. The stellate shaped cells are associated with a reticulum.
|
|
|
 |
|
|
|
Fig. c2t3D8: At the periphery of the clusters of plump, round cells, dendritic cells, which are immunoreactive for factor XIIIa, are interspersed among stellate cells. It is as if the actions of the dendritic cells modify the functions of the stellate cells, and alter the character of the matrix; the matrix becomes mucinous, and less fibrous. In the fiber-free, mucinous matrix, the cells lose their associations with reticular fibers and become rounded in outline.
|
|
|
 |
|
|
|
Fig. c2t3D9: Cellular lesions show an admixture of stellate and round (epithelioid) cells. In myxoid zones, cells are loosely spaced. The drawing to the right includes a distinctive vessel centrally; it has a thickened, delicately fibrous wall in which round cells are entrapped. Red blood cells are represented in the lumen. The endothelium is yellow.
|
|
