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mammary adenosis

Saturday 28 November 2015

Adenosis of the breast


Definition: Adenosis of the breast is any hyperplastic process primarily involving glands (i.e. an increased number of glandular components). It is common, benign, often accompanied by fibrosis. It is a part of mammary fibrocystic changes.

It can present as a mass (as nodular adenosis or adenosis tumor) or as calcifications on imaging.

With some types ( sclerosing adenosis ), the risk of subsequent breast cancer is 1.5-2x higher


- microglandular adenosis

- sclerosing adenosis

Microscopical subtypes

- nodular adenosis / adenosis tumor

Microscopical subtypes

- simple adenosis
- tubular adenosis
- adenomyoepithelial adenosis
- apocrine adenosis
- microglandular adenosis
- sclerosing adenosis
- blunt duct adenosis (now classified as " columnar cell change ")

Differential diagnosis

- mammary invasive carcinoma

  • Irregular adenosis must not be confused with invasive carcinoma.
  • high molecular weight cytokeratin can be helpful in all but the microglandular varieties in distinguishing benign from malignant.
  • The most helpful clues often come at low power where adenosis will retain a semblance of the lobular architecture.

See also

- mammary epithelial anomalies

- epithelial anomalies

  • glandular adenosis

- adenosis