Therefore, when amastia patients receive medical ultrasound examination, asymmetry or disproportioned mammary tissue may be found. Causes
Unilateral amastia is usually caused by Polands syndrome, which is characterized by one side absence of breast. The absence or dysfunction of pectoralis muscle and ribs are common case. It can also be part of other syndromes as described in the previous contents. Other causes may include intra-uterine exposure to teratogenic drugs such as dehydroipiandrosterone and methiamozole/carbimazole treatment during first trimester.For bilateral amastia, the cause has not been well understood so far. It may be related to gene mutation since often patients with bilateral amastia are diagnosed as autosomal dominant and recessive inheritance. Decreasing blood flow in the subclavian artery may also be a cause of amastia.Amastia can also be caused by injuries. These injuries may happen when patients receive surgery, such as thoracotomy, chest tube placement, or when they are treated by radiotherapy. Improper biopsy or severe burns of breast tissue may also result in amastia. Genetics
Congenital amastia can be associated with both autosomal dominant and recessive inheritance. However, in clinical research, autosomal recessive heritage amastia is uncommon.Mutation of genes may disrupt the normal process and results in abnormity of breast. The protein tyrosine receptor type F gene (PTPRF) is particularly important in nipple-areola region development. PTPRF encodes protein phosphatase which can localize at adherent junction. This phosphatase may also regulate epithelial cell to enable cell- cell interaction. PTPRF is also responsible for growth factor signalling and Wnt pathway.
Pagetoid reticulosis (also known as "acral mycoses fungoides", "localized epidermotropic reticulosis", "mycosis fungoides palmaris et plantaris", "unilesional mycosis fungoides", and "Woringer–Kolopp disease") is a cutaneous condition, an uncommon lymphoproliferative disorder, sometimes considered a form of mycosis fungoides. : 734

Symptoms and Signs
Lesions emerge as well-demarcated psoriasiform or hyperkeratotic patches and plaques, with a central clearing and an elevated border. Pagetoid reticulosis is a very slow progressive variant of mycosis fungoides and is usually localized unlike the latter. Treatment
The most common method of treatment includes radiotherapy and/or surgical excision. See also
Pagetoid
Cutaneous T-cell lymphoma
List of cutaneous conditions

References


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