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Alias/Synonym: Carcinoma Subset

CPT Code: 88342

Specimen Type, Preferred:
Formalin fixed paraffin embedded tissue
Specimen Type, Alternate:
Sample Quantity, Preferred:
1 block
2 slides
Sample Quantity, Minimum:
Transport Container:
Paraffin block
Unstained slides
Transport Temperature:
Room temperature
Collection Instructions:
Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.
Slides should be positively charged and cut at 3-4 microns for each stain/antibody ordered.
Specimen Stability:
Rejection Criteria:
No liquid specimens.
Uncharged slides
Clinical Significance:
Cytokeratin 20 has been demonstrated to be almost entirely confined to the gastric and intestinal epithelium, urothelium and Merkel cells of the skin. Cytokeratin 20 is less acidic than other type I cytokeratins and is of interest due to its restricted tissue expression. In normal tissue, cytokeratin 20 is expressed in intestinal epithelium, gastric foveolar epithelium, a number of endocrine cells in the upper portions of the pyloric glands, urothelium and Merkel cells in epidermis. In tumors it is reported, there is a marked difference in the expression of cytokeratin 20 within different carcinomas. Neoplasms expressing cytokeratin 20 are derived from normal epithelia which themselves expressed cytokeratin 20. Colorectal carcinomas consistently express cytokeratin 20, while gastric adenocarcinomas express cytokeratin 20 to a lesser degree Adenocarcinomas of the gall bladder and bile duct, ductal cell adenocarcinomas of the pancreas, mucinous ovarian tumors, Merkel cell tumors and transitional cell carcinomas have also been reported to express cytokeratin 20. 
Turnaround Time:
1 day(s)
Reference Ranges: