22 THE TONER LECTURES. 



Now I will Bot affirm that such mistakes account for the 

 opinions of those who believe that a proliferation of the nuclei 

 of the muscular fibres contributes to the cancerous mass ; but I 

 point it out as a possible source of error, and must admit that 

 most generally the cell infiltration between the fibres accumu- 

 lates to such an extent, before the latter imdergo any note- 

 worthy alteration, that it is difficult to trace their ultimate fate. 



I invite your attention next to a series of illustrations of 

 growths situated in the female breast. 



The first group are taken from a tumor of the right breast, 

 weighing over five pounds, which was removed in November, 

 1870, from the breast of an apparently healthy young woman. 

 (Surgical section, No. 5734.) The tumor had grown rapidly, 

 was freely movable, and there was no retraction of the nipple. 

 Seen quite recently the patient was apparently in good health, 

 and there has been as yet no recurrence. 



When received fresh at the Museum the tumor, on section, 

 was pinkish gray, semi-translucent, and yielded an abundant 

 transparent albuminous juice in which but few cellular elements 

 could be detected. On microscopical- examination it proved to 

 be made up of nearly normal gland-ducts and gland-vesicles 

 pushed well apart by a luxuriantly developed connective tissue 

 stroma, through which numerous small cells were scattered. 

 (Four photographs, Nos. 33 to 36, shown.) 



Such growths have been called adenoma by some, sarcoma 

 by others, and have been ranked among non-malignant tumoi^s. 

 Sometimes they affect a small portion of the gland only, at 

 other times the greater part, or the whole. With the former 

 group of cases I have had little personal experience ; as to 

 the latter, I well remember a case quite similar to this, though 

 in an older patient, which I described in 1859, in the Ameri- 

 can Journal of the Medical Sciences,* and supposed, at the 

 time, to be non-malignant. Nevertheless it speedily retnrned 



* Vol 37j Kew Scaries, p. 67. 



