CAECINOMA OF THE MAMMA. 453 



and external oblique muscles of the abdomen, as far inwards as 

 the margin of the sternum, and outwards well over the serratus 

 magnus to practically the mid-axillary line. This extensive area 

 must be remembered when it is requisite, as in excision for 

 carcinoma, to remove the whole of the glandular tissue. 



Malignant disease of the mamma infiltrates the peri-glandular 

 connective tissue, and disseminates by the lymphatic vessels so 

 abundant in it. Hence it is that three of the most characteristic 

 signs of mammary carcinoma are not infrequently in evidence, 

 although too much stress cannot be laid on the fact that cancer 

 of the breast ought to be diagnosed long before the signs are 

 present, should the patient come at this early stage. Nothing 

 is more reprehensible than to wait for their appearance before 

 warning the sufferer of her serious complaint and advising 

 adequate treatment. The three signs are, (1) The skin becomes 

 adherent, and creases or puckers when moved or pinched over 

 the site of the disease. This is due to the contraction of the 

 fibrous bands, surrounding and invaded by the growth, and 

 passing from the gland to the over-lying skin. (2) The nipple 

 becomes retracted. Again this is due to contraction of the con- 

 nective tissue around the affected acini, which tissue is continuous 

 superficially with that about the ducts passing through the nipple. 

 (3) Lymphatic glands become palpably enlarged. The gland is 

 everywhere freely supplied with lymphatics which form peri- 

 acinous and peri-ductal networks. Afterwards these are gathered 

 up in the interlobar trunks, and there is a free anastomosis 

 between these latter and the vessels found in the subcutaneous 

 tissue covering the gland, and in the pectoral fascia upon which 

 it lies. The efferent lymphatic vessels from the gland pass to at 

 least three sets of lymphatic nodes. The majority go directly into 

 the anterior axillary nodes, placed beneath the outer margin of 

 the pectoralis major. Through these the lymph may carry the 

 carcinomatous material to the central or deep nodes arranged 

 along the axillary artery and vein, and so to the nodes below 

 and above the clavicle. Other lymphatics, chiefly from the upper 

 and inner quadrant of the mamma, pass directly through the 



