—This appears especially about the time of the menopause, when glandular structure has disappeared and only ducts remain. It is common, without reference to cancer in these instances, to find cystic dilatation of numerous ducts, which vary in size from a mustard seed to that of a cherry. These are referred to by Sutton and others as involution cysts. They are filled with mucoid material and have a bluish tint. They occur usually upon the under surface of the gland. Such cystic breasts are common, and when appearing in diffused form may be easily mistaken for cancer. Pain is not frequent. This condition is certainly a precancerous stage, since the dilated ducts are often the starting points of cancer, and occasionally of papillomatous or villous outgrowths from their walls.
Duct cancer implies the form which arises in these dilated ducts, most commonly in the terminal branches, appearing ordinarily as a single tumor, but sometimes as a mass of separate nodules. Intracystic and intracanalicular growths of this character are often found. When assuming the truly cancerous phases they may be spoken of as duct cancers, otherwise as duct papillomas. They have generally been referred to as intracanalicular fibromas. Duct cancers are less tense than the preceding variety, and when situated near the surface often discolor the skin. It is from these cases that there is seen a more or less abundant discharge of fluid resembling bloody milk. These tumors grow slowly, lymphatic involvement is late, and in general they present the least malignant forms of breast cancer.
PLATE XXVII
FIG. 1
Scirrhus Carcinoma of Breast. (Middle power.)
FIG. 2
Soft Infiltration Carcinoma of Breast, showing Stroma. (Mallory’s connective-tissue stain.)
Carcinoma of sebaceous glands is by all means most common in those specialized glands named after Tyson, occurring about the prepuce. They give rise to the usual forms of cancer in this locality.