title: Prostate basal cell lesions can be negative for basal cell keratins: a diagnostic pitfall.
abstract: BACKGROUND
  Prostate basal cell lesions can have architectural and cytologic atypia that mimic prostate adenocarcinoma. Immunohistochemical stains for basal cell markers are most helpful in the differential diagnosis. All of the published studies show basal cell lesions are positive for basal cell keratins, whereas adenocarcinoma is negative for both. We reported two cases of prostate basal cell lesions with negative basal cell keratin expression by immunohistochemistry.
  
  
  METHODS
  We reported the histologic and immunohistochemical profiles of two cases of basal cell lesions of the prostate.
  
  
  RESULTS
  Histologically, both cases were highly suspicious for prostate adenocarcinoma with infiltrative growth pattern and significant nuclear atypia. The atypical glands in both cases were negative for basal cell keratins. However, both lesions were positive for another basal cell marker, p63, confirming that they were basal cells in origin, rather than prostate adenocarcinoma.
  
  
  CONCLUSIONS
  Prostate basal cell lesions can occasionally be negative for basal cell keratins by immunohistochemistry and therefore may be misdiagnosed as prostate adenocarcinoma. We recommend using both p63 and basal cell keratins simultaneously in the workup of atypical prostate lesions to avoid such a misdiagnosis.
authors.affiliation: Department of Anatomic Pathology, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA. zhoum@ccf.org
authors.forename: Ming
authors.initials: M
authors.lastname: Zhou
authors.forename: Cristina
authors.initials: C
authors.lastname: Magi-Galluzzi
authors.forename: Jonathan I
authors.initials: JI
authors.lastname: Epstein
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis*; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D011467:Prostate; D011470:Prostatic Hyperplasia / Q000175:diagnosis* / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000175:diagnosis*
chemical_list: D014408:Biomarkers, Tumor; C081876:CKAP4 protein, human; D008565:Membrane Proteins; D007633:Keratins