|Classification and external resources|
Amastia refers to a condition where breast tissue, nipple, and areola is absent, either congenitally or iatrogenically. Amastia in girls can be treated with augmentation mammoplasty.
Amastia differs from amazia (which involves only the absence of breast tissue; the nipple and areola remain present), although the two conditions are often (erroneously) thought to be identical. The terms "amastia" and "amazia" are thus often used interchangeably, even though the two conditions are medically different.