534 



TUMORS. 



(a) In the variety termed scirrhus, or hard cancer, the con- 

 nective tissue is comparatively abundant and well developed, 

 either of loose, fibrous structure or compact, almost homogene- 

 ous. The epithelia are small, and arranged in narrow alveoli 

 or in tracts, irregularly distributed throughout the connective 

 tissue. (See Fig. 221.) 



The connective tissue is fully developed, but scantily sup- 

 plied with blood-vessels. The small, polyhedral epithelia are 

 separated from each other by light, narrow rims of cement- 

 substance, but interconnected by conical filaments, in the same 

 way as normal epithelia. The epithelia are clustered together in 

 small, irregular masses, and between the clusters and the adja- 

 cent connective tissue, in preserved specimens, a narrow space is 



FIG. 221. SCIRRHUS, OR HARD CANCER OF THE 

 FEMALE BREAST. 



N, alveolus, filled with epithelia; CF, connective-tissue frame, with (CC) clusters of 

 plastids, the connective-tissue corpuscles ; PP, rows of epithelia, probably sprung from con- 

 nective tissue. Magnified 600 diameters. 



often observed, containing granular matter or mucous globules, 

 which are considered to be the offspring of endothelia, lining the 

 inner surface of the connective-tissue cavity. 



This variety is the least malignant and the slowest in its 

 growth. It appears most frequently as a primary tumor in the 

 female breast, at the side of the nipple, often retracting the 

 nipple and producing folds in the skin. The comparative 



