• Immunohistochemistry (IHC)
Anti-cytokeratin clone OSCAR (CK OSCAR) demonstrates a broad spectrum of cytokeratin reactivity. In normal tissues, OSCAR is reactive with most epithelial types, including bile ducts and hepatocytes in liver, bladder epithelium, breast ducts, bronchial epithelium, endometrium, intestinal epithelium of stomach, duodenum, ileum, colon, rectum, pancreas, ovarian epithelium, pancreatic acini, pituitary acini, pneumocytes, prostate, thyroid, skin (positive on the basal layer and negative on the superficial layers of squamous epithelium), and apocrine and sweat glands. In tumors, OSCAR is reactive with most carcinomas, including breast, transitional cell (TCC), renal cell (RCC), lung adenocarcinoma, lung small cell, lung squamous cell, endometrial, prostate, ovarian, hepatocellular (HCC), colorectal CA, stomach and thyroid. It is negative in certain normal tissues, including brain, lymphocytes and all cells of hematolymphoid origin, muscle, brain, nerves, endothelium and in certain tumors including most melanomas, sarcomas, lymphomas, primitive neuroectodermal tumors (PNET)/Ewings and gastrointestinal stromal tumors (GIST). Positivity has been seen on some dendritic cells in lymph nodes, some endothelia, and some muscle cells.
Turnaround time
1 Day

Level of Service

  • Technical Only
New York Approved: Yes

Specimen Requirements

A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen type or one (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4-5 microns) for each test/antibody ordered. Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.

Storage and Transportation

Use cold pack for transport, making sure cold pack is not in direct contact with specimen. NYS clients please provide date and time of Collection.

CPT Code(s)*

88342 x 1 or 88341 x 1

*The CPT codes provided with our test descriptions are based on AMA guidelines and are for informational purposes only. Correct CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed.

Last Updated: January 22, 2025

Get in touch

Our Client Services team is on hand to help. Please call us at 866.776.5907, Option 3.