OSCAR cytokeratin

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

Revised: 12 December 2015, last major update July 2013

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

PubMed Search: CK Oscar, Oscar Keratin
Cite this page: OSCAR cytokeratin. website. Accessed May 21st, 2018.
Definition / general
  • Also called CK Oscar or Oscar Keratin
  • Interpretation: cytoplasmic staining
Uses by pathologists
  • Broad spectrum keratin; distinguishes carcinomas from non-epithelial malignancies
Microscopic (histologic) images

Images hosted on
Missing Image

Alveolar rhabdomyosarcoma (fig B)

Positive staining - normal
  • Epithelium of bile ducts, bladder (urothelium), breast ducts, bronchi, colorectum, duodenum, endometrium, ileum, ovary, pancreas, prostate, stomach and thyroid
  • Also hepatocytes, pituitary acini and pneumocytes
Positive staining - disease
Negative staining
  • Brain, endothelium, lymphocyte, muscle and nerves
  • GIST, lymphoma, melanoma, sarcoma and schwannoma