Test Code KRT7 Keratin 7 (KRT7) Immunostain, Technical Component Only
Advisory Information
This test includes only technical performance of the stain (no pathologist interpretation is performed). If diagnostic consultation by a pathologist is required order PATHC / Pathology Consultation.
Shipping Instructions
Attach the green pathology address label and the pink Immunostain Technical Only label included in the kit to the outside of the transport container.
Specimen Required
Supplies: Immunostain Technical Only Envelope (T693)
Specimen Type: Tissue
Container/Tube: Immunostain Technical Only Envelope (T693)
Preferred: 2 Unstained positively charged glass slides (25- x 75- x 1-mm) per test ordered; sections 4-microns thick.
Acceptable: Formalin-fixed, paraffin-embedded (FFPE) tissue block
Additional Information:
1. Information on accessing digital images of immunohistochemistry (IHC) stains and the manual requisition form can be accessed through this website: www.mayomedicallaboratories.com/test-info/ihc/index.html
2. Clients ordering stains using a manual requisition form will not have access to digital images.
3. Clients wishing to access digital images must place the order for IHC stains electronically. Information regarding digital imaging can be accessed through this website: www.mayomedicallaboratories.com/test-info/ihc/faq.html
Useful For
Aids in determining primary site in carcinomas of unknown origin
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
IHTOI | IHC Initial, Tech Only | No | No |
IHTOA | IHC Additional, Tech Only | No | No |
Method Name
Immunohistochemistry
Reporting Name
Keratin 7 IHC, Tech OnlySpecimen Type
TECHONLYSpecimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
TECHONLY | Ambient (preferred) | |
Refrigerated |
Reject Due To
Hemolysis |
NA |
Lipemia |
NA |
Icterus |
NA |
Other |
Wet/frozen tissue |
Clinical Information
Keratin 7 (KRT7) stains the cytoplasm of epithelial cells in a granular and/or filamentous pattern, or may appear membrane associated (cytoskeletal). In normal tissues, KRT7 is found in a large number of cell types including many ductal and glandular epithelia (biliary and pancreatic ducts, lung alveoli, breast, ovary, endometrium, renal collecting ducts, urothelium, thyroid, placental trophoblasts, and mesothelium). When used together, KRT7 and KRT20 may be useful as an aid in determining primary site in carcinomas of unknown origin.
Interpretation
This test includes only technical performance of the stain (no pathologist interpretation is performed). Mayo Clinic cannot provide an interpretation of tech only stains outside the context of a pathology consultation. If an interpretation is needed, refer to test code PATHC / Pathology Consultation for a full diagnostic evaluation or second opinion of the case. All material associated with the case is required. Additional specific stains may be requested as part of the pathology consultation, and will be performed as necessary at the discretion of the Mayo pathologist.
The positive and negative controls are verified as showing appropriate immunoreactivity and documentation is retained at Mayo Clinic Rochester. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request. Contact 855-516-8404.
Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.
Cautions
No significant cautionary statements
Method Description
Immunohistochemistry on sections of paraffin-embedded tissue.(Unpublished Mayo method)
Day(s) and Time(s) Performed
Monday through Friday
Analytic Time
1 daySpecimen Retention Time
Until staining is complete.Performing Laboratory

Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
88342-TC, primary
88341-TC, if additional IHC
LOINC Code Information
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
70800 | Keratin 7 IHC, Tech Only | No LOINC Needed |