Test Code P16 p16 (INK4a/CDKN2A) 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 slide (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 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 the identification of human papilloma virus infection
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
p16 (INK4a/CDKN2A) 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
p16 (INK4a/CDKN2A) is a cell cycle regulatory protein that is overexpressed in cervical dysplasia related to human papilloma virus (HPV) infection. Nuclear and cytoplasmic staining is seen in dysplastic squamous cervical epithelial cells infected with HPV, but not in normal cells. A subset of pancreatic islet cells and dendritic cells show expression of p16, and can serve as positive control.
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.
Clinical Reference
1. Castle PE: A LASTing impression: incorporating p16 immunohistochemistry into routine diagnosis of cervical neoplasia. Pathol Case Rev 2013;18:154-157
2. Doxtader EE, Katzenstein AL: The relationship between p16 expression and high-risk human papillomavirus infection in squamous cell carcinomas from sites other than uterine cervix: a study of 137 cases. Human Pathol 2012;43:327-332
3. El-Naggar AK, Westra WH: p16 expression as a surrogate marker for HPV-related oropharyngeal carcinoma: a guide for interpretative relevance and consistency. Head Neck 2012;34:459-461
4. Klaes R, Benner A, Friedrich T, et al: p16INK4a immunohistochemistry improves interobserver agreement in the diagnosis of cervical intraepithelial neoplasia. Am J Surg Pathol 2002;26(11):1389-1399
5. Singhi A, Westra WH: Comparison of human papillomavirus in situ hybridization and p16 immunohistochemistry in the detection of human papillomavirus-associated head and neck cancer based on a prospective clinical experience. Cancer 2010;116:2166-2173
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 has been modified from the manufacturer's instructions. Its performance characteristics were 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 |
---|---|---|
70836 | p16 (INK4a/CDKN2A) IHC, Tech Only | No LOINC Needed |