GLANDULAR CARCINOMATA. 193 



§ 159. The microscope tlioroiiglily corroborates the evidence 

 of the unaided eje. In fig. 61, the microscopic appearances 

 presented by fine sections taken from each of the four zones of 

 the tumour are shown. Fig. 61, «, is from the periphery of a 

 minute nodule, situated in the zone of development ; the appear- 

 ances which it presents used to be interpreted as follows. It 

 was supposed that each row of small round-cells were at once 

 the brood of a single connective-tissue corpuscle which formerly 

 occupied the same point, and the forerunners of a group of 

 cancer-cells, such as might be observed in their immediate 

 neighbourhood. This developmental nexus has now been broken 

 through. The rows of round-cells are viewed as colourless 

 corpuscles which have migrated from the blood-vessels; and 

 great efforts are being made to prove that the nests of cancer- 

 cells originate exclusively from the pre-existing epithelia of the 

 gland-substance. To my mind these efforts appear futile, so 

 far as they are meant to show that all the cancer-cells are 

 actually "descendants" of the epithelial cells. On the other 

 hand I am quite willing to admit that in the hard form of 

 glandular cancer, as in the other varieties, the glandular epithelia 

 undergo fissiparous multiplication, contributing thereby, though 

 only to a moderate extent, towards the enlargement of the acini 

 or tubuli ; also, that the first nests of cancer-cells usually 

 originate in immediate proximity to the glandular epithelia, thus 

 giving no little colour to the assumption of an " epithelial infec- 

 tion " of the round-cells wdiicli are heaped up in the connective 

 tissue. In my opinion, the development of hard glandular cancer 

 occurs by a slow interstitial inflammation, whose cellular pro- 

 ducts are converted into epithelial elements instead of pus or con- 

 nective tissue. The active participation of the glandular epithelia 

 must be regarded as the primary cause of this inflammation, and 

 as the exciting cause of the peculiar line taken by the products 

 of inflammation in their development. Hence the glandular 

 epithelium is and must remain the essential cause of the morbid 

 action, even though its co-operation happen to be quantitatively 

 insignificant. The precise way in which an epithelial direction 

 is given to the development of the infiltrated products of inflam- 

 mation must for the present be left undecided ; although, as has 

 been already hinted, there are many reasons for assuming that 

 young epithelial cells penetrate one by one into the interstices 



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