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Test Code P27 p27 (KIP1/CDKN1B) 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

Secondary ID


Useful For

Identifying B-cell neoplasms

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


Reporting Name

p27 (KIP1/CDKN1B) IHC, Tech Only

Specimen Type


Specimen Stability Information

Specimen Type Temperature Time
TECHONLY Ambient (preferred)

Reject Due To








Wet/frozen tissue
Cytology smears
Nonformalin fixed tissue
Nonparaffin embedded tissue
Noncharged slides
ProbeOn slides

Clinical Information

p27 (KIP1/CDKN1B) is a cyclin-dependent kinase inhibitor (CDKI) involved in G1 arrest. p27 binds to the cyclinCDK complexes, cyclinECDK2, cyclinACDK2, and cyclinD1CDK4, to inhibit cell cycle progression. Loss or reduced expression of p27 is associated with poor outcome in carcinoma of breast, prostate, gastrointestinal tract, and lung. p27 can be useful in diagnosis of B cell neoplasms, with mantle cell lymphoma usually lacking expression of this protein. Normal mantle zone lymphocytes and T cells express p27.


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.

Clinical Reference

1. Saez AI, Saez AJ, Artiga MJ, et al: Building an outcome predictor model for diffuse large B-cell lymphoma. Am J Pathol 2004;164(2):613-622

2. Sqambato A, Cittadini A, Faraglia B, et al: Multiple functions of p27Kip1 and its alterations in tumor cells: a review. J Cell Physiol 2000;183(1):18-27

3. Sherr CJ, Roberts JM: CDK inhibitors: positive and negative regulators of GI-phase progression. Genes Dev 1999;13:1501-1512

Day(s) and Time(s) Performed

Monday through Friday

Analytic Time

1 day

Performing Laboratory

Mayo Medical Laboratories in Rochester

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
70837 p27 (KIP1/CDKN1B) IHC, Tech Only No LOINC Needed


If not ordering electronically, complete, print, and send an Immunohistochemical (IHC)/In Situ Hybridization (ISH) Stains Request Form (T763) (