Amastia
Citation, DOI, disclosures and article data
At the time the article was created Avni K P Skandhan had no recorded disclosures.
View Avni K P Skandhan's current disclosuresAt the time the article was last revised Tariq Walizai had no financial relationships to ineligible companies to disclose.
View Tariq Walizai's current disclosures- Absence of breast tissue
- Absent breast tissue
Amastia is a rare congenital condition characterized by the absence of breast tissue, nipple and areola. This may occur unilaterally or bilaterally.
Pathology
During embryological development, breasts first appear as ectoderm ridges during the 6th week of gestation. This ridge grows thicker and leads to mesodermal compression. With further proliferation of the ectodermal cells there is a growth of the same into the mesodermal layer leading to a formation of clusters which further form lobules. In the fifth month of gestation some cords of ectodermal cells sprout from each of these lobules with the central parts undergoing apoptosis leading to formation of ducts. Similarly on the surface, apoptosis occurs leading to formation of pits which protrude through the nipples after connecting with the formed ducts. An inhibition at any one stage of this development leads to hypoplasia or aplasia of the breast
Unilateral amastia
Defined as amastia involving just one side. It is often seen to be associated with absence of pectoral muscle in setting of Poland syndrome.
Bilateral amastia
In these cases there is amastia on both sides. It is often associated with many other congenital anomalies.
Etiology
Congenital
Acquired
teratogen exposure
thoracotomy-associated injuries
radiotherapy burns
See also
amazia: absence of breast glandular tissue with preservation of nipple-areolar complex
References
- 1. Guray M, Sahin AA. Benign breast diseases: classification, diagnosis, and management. Oncologist. 2006;11 (5): 435-49. Oncologist (full text) - doi:10.1634/theoncologist.11-5-435 - Pubmed citation
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