Breast profile:

A ducts

B lobules

C dilated section of duct to hold milk

D nipple

E fat

F pectoralis major muscle

G chest wall/rib cage

Enlargement:

A normal duct cells

B basement membrane

C lumen (center of duct)

Lymph node areas adjacent to breast area.

A pectoralis major muscle

B axillary lymph nodes: levels I

C axillary lymph nodes: levels II

D axillary lymph nodes: levels III

E supraclavicular lymph nodes

F internal mammary lymph nodes