The term has several meanings on histological and symptomatic levels and on both levels usage overlaps with mastalgia, fibrocystic disease and specific sub- or superclasses of nonpuerperal mastitis. While this is not ideal for a definition it results from actual usage in international literature. Because research literature regarding<unk><unk>  is anything but abundant it is probably easiest to determine the exact meaning(s) intended by the respective authors on a case by case basis and this section can offer only a few hints. Typical usage in North America is a synonym of nonpuerperal mastitis, including the special cases of granulomatous mastitis, comedo mastitis, subareolar abscess with or without squamous metaplasia of lactiferous<unk> s and fistulation. Simple<unk>  widening should be carefully distinguished from more complex histological changes.
Duct ectasia of breast
Papillomatosis of breasts
Breast cyst
Adenomyoepithelioma of the breast
Breast eczema
Mucinous carcinoma of the breast
Keratin implantation cyst
Solitary cutaneous leiomyoma