4 The Ohio Journal of Science [Vol. XVIII, No. 1, 



although at times, as in this specimen, all the neoplastic cells 

 are fibroblasts and there is no evidence of either bone or cartilage 

 formation. This tumor, however, arose from or near the 

 periosteum. From this close association with bone, it has been 

 suggested that these giant cells were identical with osterclasts. 

 This type, Mallory says, (loc. cit.) "Is due to endothelial 

 leukocytes invading tumors, especially those involving bone, 

 and fusing to form foreign body giant cells. They are not tumor 

 cells (although the tumors containing them are the ones which 

 receive the name giant cell sarcomas) and usually signify only 

 erosion and disintegration of bone." In addition to this 

 source, the origin of osteoclasts has been assigned to reticular 

 cells and to osteoblasts. 



It would be of interest then to determine if possible whether 

 the giant cells in this fibroblastoma were really brought about 

 by a fusion of cells as they appear to have been and also whether 

 the cells which entered into their formation were tumor cells 

 or were cells that had infiltrated the tumor from some outside 

 source. 



Sections from this specimen were impregnated with silver 

 after the method of Maresch-Bielskowsky. By using this 

 method. Dr. James H. Warren has studied the nature of the 

 giant cell seen in early tubercles ('17). This technique as 

 employed b}^ Ferguson ('12) would appear to be well established 

 as a specific stain for reticular fibrils. These fibrils are 

 abundant in this tumor. This is not surprising when it is 

 considered that this is a tumor of rather slow growth arising 

 in the connective tissue of the jaw. Some of these fibrils appear 

 to leave the cytoplasm, and are seen free, while others bear 

 only a faint rim of cytoplasm. The giant cells are especially 

 interesting when stained with this silver impregnation. In 

 many of the smaller giant cells, which contain only a few 

 irregularly placed nuclei, the arrangement of fibrils together 

 with the outline of the protoplasm suggests that the giant 

 cells have been formed by the fusion of the reticular cells. 

 Even in some of the larger giant cells, reticular fibrils can be 

 seen in the cell body. These facts together with the complete 

 absence of any evidence of mitosis would make it appear that 

 these cells have been formed by a fusion of the reticular cells 

 rather than by the fusion of invading cells or by multiple 

 mitosis of the tumor cells. 



This specimen represents a neoplasm of slow growth in 

 close association with bone. Since there are normally reticular 



