Stains
Cytokeratin 34 beta E12

Author: Kara Hamilton, M.S., Nat Pernick, M.D. (see Authors page)

Revised: 11 December 2015, last major update July 2013

Copyright: (c) 2003-2015, PathologyOutlines.com, Inc.

PubMed Search: 34betaE12
Cite this page: Cytokeratin 34 beta E12. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/stainsck34be12.html. Accessed December 4th, 2016.
Definition / General
  • High molecular weight keratin relatively specific for prostate basal cells
  • Reacts to CK1, CK5, CK10 and CK14 and possibly other keratins
  • Also called CK903, high molecular weight keratin
Uses by Pathologists
Micro Images

Images hosted on Pathout server:

Thyroid anaplastic carcinoma

Prostate: Normal



Images hosted on other servers:

Prostate: Basal cell hyperplasia

Prostate: Post-atrophic hyperplasia

Atypical adenomatous hyperplasia


Staining without and with antigen retrieval

High grade PIN: with adenocarcinoma


Prostatic adenocarcinoma is negative with occasional positive benign glands


Adenoid basal cell tumor

Low-grade bladder neoplasms



Images hosted on Nature.com:

Kidney: collecting duct carcinoma with signet ring features

Prostate: Atrophy with pseudoinfiltrative growth pattern

Prostate: Sclerosing adenosis

Atypical adenomatous hyperplasia


High grade PIN: #1-tufting pattern with 34BE12 staining; #2-micropapillary pattern; #3-flat pattern; #4-with foamy cytoplasm


Urothelial type adenocarcinoma with
mucin production is focally 34BE12+


Positive Staining - Normal
Positive Staining - Not Malignant
Positive Staining - Malignant
Negative Staining