title: Patterns of differentiation and proliferation in intraductal carcinoma of the prostate: significance for cancer progression.
abstract: BACKGROUND
  Cribriform prostatic intraepithelial neoplasia (C-PIN) identifies a unique histological pattern: dysplastic cells line ductal/acinar walls but also span across gland lumens. C-PIN is distinct from other forms of dysplasia; it is seldom seen except within invasive cancer, it is more frequent in larger/higher-grade cancers; and it appears to contribute independently to aggressive behavior. Hence, C-PIN may represent a separate, more aggressive entity: intraductal carcinoma of the prostate (IDC-P). Here, support for that distinction stems from a histologic/biologic subclassification of IDC-P, whose elements are linked to features of invasive cancer.
  
  
  METHODS
  Histologic criteria were tested against 26 radical prostatectomies, using immunostains for prostate-specific antigen, MUC-2, androgen receptor (differentiation), and Ki-67 (proliferation). Invasive cancer grade, stage, and follow-up were compared.
  
  
  RESULTS
  Architecture of the central (luminal) cell compartment defined three subclasses of IDC-P: A (trabecular), B (cribriform), and C (solid/comedo), which represented progressive dedifferentiation with a reciprocal increase in proliferation. The IDC-P subpattern correlated with cancer stage, grade, and clinical course.
  
  
  CONCLUSIONS
  IDC-P is a separate entity, distinct from PIN; cancers associated with IDC-P are more aggressive than those associated with only PIN. It comprises a spectrum of histological patterns which appear to be determined in concert with invasive cancer, whose prognosis it worsens.
authors.affiliation: Urological Research Centre, University of Western Australia, Perth, Western Australia, Australia. ronnie@urc.uwa.edu.au
authors.forename: R J
authors.initials: RJ
authors.lastname: Cohen
authors.forename: J E
authors.initials: JE
authors.lastname: McNeal
authors.forename: T
authors.initials: T
authors.lastname: Baillie
mesh_terms: D002277:Carcinoma / Q000473:pathology*; D002454:Cell Differentiation; D002455:Cell Division; D003593:Cytoplasm / Q000473:pathology; D018450:Disease Progression; D006801:Humans; D007158:Immunologic Techniques; D008297:Male; D011471:Prostatic Neoplasms / Q000473:pathology*; D013194:Staining and Labeling