Following untreated mastitis, breast<unk>  could occur. 
Breast<unk>  is usually caused by staphylococcus aureus bacterial infection to an injured breast skin. Staphylococcus aureus could form<unk>  by secretion of several killing agents like enzymes and toxins which causes breast tissue necrosis. In a reaction to these bacterial substances, assembled white blood cells in this tissue produces anti-bacterial anti-bodies that help in killing the bacteria. However, these cells cause damage to the soft tissue contributing in the<unk>  formation. 
As the breast<unk>  is the complicated form of mastitis, the pathophysiology is mostly like the mastitis pathophysiology.
Breast abscess pathophysiology
Breast abscess causes
Paget's disease of the breast pathophysiology
Rhabdomyosarcoma laboratory findings
Breast cancer pathophysiology
Liposarcoma staging
Oral cancer pathophysiology
Lipoma pathophysiology