434 



BENIGN TUMOURS. 



I am noi aware that these tumours grow witliin the shell of 

 a bone, as in the human being, but on the outside, and gene- 

 rally fastened to the bony wall and invested by the periosteum, 

 which is greatly thickened and overgrown. When cut with 



the knife, they present a bright, 

 greyish, translucent, or pinky- white 

 appearance, and sometimes coarsely 

 granular, or opaque, with gritty points, 

 as if gradually ossifying. When ex- 

 amined microscopically, they are 

 found to consist of cartilage cells, 

 mixed with fibres of white fibrous 

 tissue. The fibres are very deli- 

 cate and tufted, and contain the 

 cartilage cells, either singly or in 

 groups. 

 Fig. 102.— Proliferation of The Only change that occurs in 



diseased cartilage. Large tllCSC tumOUrS is their OSsification iuto 

 groups of cartilage cells witliin ,, . , i i • 



a common envelope (wrongly a canccllous Structure enclosed m a 



called parent cells), produced thin COmpact shell of boUC. I have 

 from single cells by successive ., „ . . , 



subdivisions. At the edge one never Seen the tatty degeneration or 

 of these groups has been cut cvstic transformation spoken of by 



through, and in it is seen a '^ jt i • j i \ •• • 



cartilage cell invested by a human pathologists; but it IS quite 



number of capsular layers (ex- 

 ternal secreted masses). 300 

 diam. — (Vircho w. ) 



possible that such a change 

 occur. 



may 



■ in 



Fig. 103. Fig. 104. 



Figs. 103 and 104. — Enchondroma. Fig. 100. Structure of a firm enchondroma. 

 The right of the figure represents, above, mineral deposit in and around the cells ; 

 and, below, some isolated cartilage corpuscles. FiG. 101. The same, after the 

 addition of acetic acid, rendering the whole — and especially the nucleus — more 

 transparent. 250 diam. — (Bennett.) 



Treatment. — The only method is their removal by excision, 

 and that as early as possible. 



