Amastia refers to a rare clinical anomaly in which both internal breast tissue and the visible nipple are absent on one or both sides. It affects both men and women. Amastia can be either isolated (the only medical condition) or comorbid with other syndromes, such as ectodermal dysplasia, syndactaly (Polands syndrome) and lipoatrophic diabetes. This abnormality can be classified into various types, and each could result from different pathologies. Amastia differs from amazia and athelia. Amazia is the absence of one or both mammary glands but the nipples remain present, and athelia is the absence of one or both nipples, but the mammary gland remains.Amastia is presumably due to failure of embryologic (before birth) mammary ridge development or incomplete involution. People with amastia often suffer from ectodermal defects, which include various syndromes such as cleft palate, isolated pectoral muscle and abnormal formation of the arms.Treatment for female amastia particularly includes psychological guidance and breast reconstruction. Because there is no breast tissue, breastfeeding is not possible. If amastia only appears on one side, then it is possible to breastfeed on the other side. Often, people with amastia decide against treatment. Classification
Amastia can be either iatrogenic or congenital. The congenital amastia are further divided into syndromic type and non-syndromic type respectively. As the definition suggests, syndromic amastia is often associated with obvious symptoms. The common case is hypoplasia of ectodermal tissue, such as hair and skin defects. On the other hand, non-syndromic amastia, shows no defects in body parts other than breast.
Once the corneal surface has stabilized, surgery is the main approach to treatment. Types of surgeries:

In the case of a partial LSCD:, a sequential sector conjunctival epitheliectomy (SSCE) can be performed to remove any tissue (pannus) that has grown over the cornea. This procedure is sometimes used as a temporary measure until further surgical interventions are possible. Transplantation of amniotic membrane from a placenta may also help. Although amniotic membrane does not have stem cells of its own, it supports regeneration of limbal stem cells. However, further surgical intervention may be needed if these approaches are unsuccessful, or when disease is more severe. Conjunctival limbal autograft (CLAU) involves transplantation of limbal tissue from a patients healthy eye. As the procedure is achieved by transplanting autologous limbal stem cells from the patients healthy eye, there is no risk of immune rejection, and hence no need for systemic immunosuppression. However, this procedure represents a risk for the donor eye, as the patient already has one eye damaged. In the case of bilateral LSCD, where both eyes are affected, it may be possible to transplant limbal tissue from a living donor (usually a relative). This is known as a conjunctival limbal allograft (CLAL). CLAL can be performed with both partial or total LSCD, the donor tissue is usually from a sibling or parent. As with CLAU, only a part of the donor limbus can be transplanted, as a live donor is being used. Being an allogenic transplant, immunosuppression is required, due to the risk of rejection.