title: Cytologic findings of atypical adenosis of the breast. A case report.
abstract: BACKGROUND
  Atypical apocrine adenosis, a well-described histopathologic entity, can sometimes be misdiagnosed as carcinoma. Apocrine cells can also appear atypical in cytopathology and be mistaken for carcinoma. Occasional case reports describe false positive cases due to the presence of apocrine cells in a few cases of radial scars and atypical apocrine metaplasia and in a degenerated cyst.
  
  
  METHODS
  A 37-year-old female underwent ultrasound-guided fine needle aspiration of an ill-defined breast nodule. The aspirate showed clusters and single cells containing abundant granular to focally vacuolated cytoplasm; enlarged, pleomorphic nuclei with irregular nuclear membranes; granular chromatin; and prominent nucleoli. These cells were distinct from and larger than the surrounding ductal and myoepithelial cells. Excision showed a nodular area of atypical apocrine adenosis adjacent to previous biopsy changes, correlating with the cytologic findings.
  
  
  CONCLUSIONS
  Atypical apocrine adenosis can mimic carcinoma in histopathology and cytopathology. One should be cautious when reviewing apocrine cells in cytology, given their atypical features, especially their single, dispersed nature. However, the presence of accompanying benign cellular elements supports a benign diagnosis. Surgical biopsy should be recommended based on the cytologic findings.
authors.affiliation: Departments of Pathology and Surgery, Box 1194, Mount Sinai Medical Center, One Gustave L. Levy Place, New York, New York 10029, USA.
authors.forename: David
authors.initials: D
authors.lastname: Kaufman
authors.forename: Miguel
authors.initials: M
authors.lastname: Sanchez
authors.forename: B
authors.initials: B
authors.lastname: Mizrachy
authors.forename: Shabnam
authors.initials: S
authors.lastname: Jaffer
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D005348:Fibrocystic Breast Disease / Q000175:diagnosis / Q000473:pathology*; D006801:Humans