Final pathology of the second excisional biopsy revealed IP, forid hyperplasia, and fibrocystic alternations (fibrosis, periductal inflammation, apocrine metaplasia
, macro-microcysts) (Figures 1-3).
(10) Apocrine proliferations include benign lesions, such as apocrine metaplasia
, apocrine adenosis, and apocrine-rich papillomas, in addition to atypical and malignant lesions, including atypical apocrine adenosis, atypical apocrine hyperplasia, apocrine DCIS, and invasive carcinoma with apocrine features.
Some of the epithelial ducts demonstrated apocrine metaplasia
and papillary formations expanding toward the lumen, which were dilated in cystic formation as typical characteristics upon macroscopic examination.
On histological examination, apocrine metaplasia
was identified but no residual tumor was detected.
Complex fibroadenoma refers to fibroadenomas with foci of cysts, sclerosing adenosis, epithelial calcifications, and papillary apocrine metaplasia
, and has a higher future risk of malignancy.
Epithelial proliferation was frequently accompanied by intraductal papillomatosis, components of fibrocystic disease (apocrine metaplasia
and hyperplasia, fibrosis, ductal ectasia), fibroadenoma, adenosis, sclerosing adenosis and chronic mastitis.
Lesions were classified as fibrocystic change with or without epithelial hyperplasia if the lesion had apocrine metaplasia
, nodular adenosis, sclerosing adenosis, papillomatosis, and usual ductal hyperplasia.
Apocrine carcinomas also known as apocrine metaplasia
or sweat gland carcinoma are very rare variant of invasive breast malignancies with an incidence less than 1%.
Papillary apocrine metaplasia
is a common papillary lesion that is associated with breast cysts.
The epithelium is often of columnar morphology and/or displays usual ductal hyperplasia (UDH) and/or apocrine metaplasia
. Less frequently, there may be squamous, chondroid, or osseous metaplasia, findings more often identified in the setting of abundant sclerosis.
 Several changes occur within epithelial element of fibroadenoma, including apocrine metaplasia
and varying degrees of epithelial hyperplasia, Apocrine metaplasia
is a fairly frequent component of fibroadenoma; however, fibroadenoma with squamous metaplasia is a rare entity.
Normal Apocrine Cells, Apocrine Metaplasia
, and Apocrine Adenosis