apocrine

File:Histopathology of apocrine metaplasia of breast, annotated.png showing apocrine metaplasia of the breast with typical features,Image by Mikael Häggström, MD. Reference for findings: {{cite web|url=https://www.pathologyoutlines.com/topic/breastapocrinemetaplasia.html|title=Apocrine metaplasia|author=Carlos C. Diez Freire, M.D., Shahla Masood, M.D.|website=Pathology Outlines}} Last author update: 28 May 2020. including apical snouts with eosinophilic granules. H&E stain.]]

Apocrine metaplasia is a reversible transformation (metaplasia) of cells to an apocrine phenotype. It is common in the breast in the context of fibrocystic change. It is seen in women mostly over the age of 50 years. Metaplasia happens when there is an irritation to the breast (breast cyst). Apocrine-like cells form in a lining of developing microcysts, due to the pressure buildup within the lumen. The pressure build up is caused by secretions.Dr Ayush Goel and Radswiki et al. Apocrine metaplasia of the breast.http://radiopaedia.org/articles/apocrine-metaplasia-of-the-breast This type of metaplasia represents an exception to the common rule of metaplasia increasing the risk for developing cancer in that apocrine metaplasia doesn't increase the possibility of developing breast cancer.{{Cite journal |last1=Wells |first1=C A |last2=El-Ayat |first2=G A |date=December 2007 |title=Non-operative breast pathology: apocrine lesions |journal=Journal of Clinical Pathology |volume=60 |issue=12 |pages=1313–1320 |doi=10.1136/jcp.2006.040626 |issn=0021-9746 |pmc=2095572 |pmid=18042688}} Metaplastic apocrine cells belong to the category of oncocytes, which are a group characterized by abundant acidophilic, granular cytoplasm (from the Greek root onco-, which means mass, bulk).

{{Main|Pure apocrine carcinoma of the breast#Apocrine ductal carcinoma in situ}}

Apocrine ductal carcinoma in situ (ACDIS) is a very rare breast carcinoma which is regarded as a variant of the ductal carcinoma in situ breast tumors. ACDIS tumors have microscopic histopathology features that are similar to pure apocrine carcinoma of the breast tumors but differ from them in that they are completely localized, i.e. have not invaded nearby tissues or metastasized to distant tissues.{{cite journal | vauthors = Quinn CM, D'Arcy C, Wells C | title = Apocrine lesions of the breast | journal = Virchows Archiv | volume = 480 | issue = 1 | pages = 177–189 | date = January 2022 | pmid = 34537861 | pmc = 8983539 | doi = 10.1007/s00428-021-03185-4 | url = }}

{{Main|Pure apocrine carcinoma of the breast}}

Apocrine carcinoma is a very rare form of female breast cancer. The rate of incidence varies from 0.5 to 4%.Khandeparkar, Siddhi Gaurish Sinai, Sanjay D. Deshmukh, and Pallavi D. Bhayekar. "A rare case of apocrine carcinoma of the breast: Cytopathological and immunohistopathological study." Journal of Cytology/Indian Academy of Cytologists 31.2 (2014): 96. Cytologically, the cells of apocrine carcinoma are relatively large, granular, and it has a prominent eosinophilic cytoplasm.{{cite web|url=http://path.upmc.edu/cases/case209/dx.html |title=Final Diagnosis -- Case 209 |access-date=2014-11-03 |url-status=dead |archive-url=https://web.archive.org/web/20000312050409/http://path.upmc.edu/cases/case209/dx.html |archive-date=2000-03-12 }} (accessed November 3, 2014) When apocrine carcinoma is tested as a “triple negative", it means that the cells of the patient cannot express the estrogen receptor, progesterone receptor, or HER2 receptor.{{Cite web|url=https://www.hopkinsmedicine.org/kimmel_cancer_center/centers/breast_cancer_program/treatment_and_services/rare_breast_tumors/apocrine_breast_cancer|title=A[pcrome Breast Cancer - Johns Hopkins Kimmel Cancer Center|first=Michelle|last=Potter|website=www.hopkinsmedicine.org}}

{{Reflist}}

• [http://www.lab.anhb.uwa.edu.au/mb140/CorePages/Epithelia/Epithel.htm#Secretory Diagram at uwa.edu.au]

{{Glands}}

Category:Exocrine system