Keratinocyte Markers, Serum (Qualitative Immunoassay for CK5/6 and p63)
This test measures specific proteins (keratinocyte markers) found in certain types of cells, often used to help assess conditions affecting skin or related tissues.
["This test helps evaluate potential skin cancer risks or other related conditions by detecting abnormal cell markers in your blood."]
Key facts at a glance
- LOINC
- 74486-2
- Short code
- CK5+p63+CK AE1 Ag Tiss ImStn
- Synonyms
- CK5+p63+CK AE1 Ag Tiss ImStn
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 22
- Ref high
- 198
- Critical range
- — – 10000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- immune-stain
- CPT
- 82553
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test detects two proteins—CK5/6 and p63—which are typically produced by keratinocytes (cells in the outer layer of skin). Elevated levels may suggest abnormal cell growth, including precancerous changes or early skin cancer.
Why It’s Ordered
Your healthcare provider may order this test if you have symptoms like persistent skin changes, a history of skin cancer, or if you’re at higher risk for certain skin-related conditions.
Common Uses
This screening test is often used alongside other diagnostic methods to monitor skin health, especially in patients with a history of basal cell carcinoma, squamous cell carcinoma, or other precancerous skin lesions.
What to Expect
A small blood sample is drawn from a vein, usually in your arm. The sample is then tested in a lab to check for the presence of CK5/6 and p63 proteins.
Reference range
Adult males: 22-198 U/L; Females: 22-198 U/LN/A
No special preparation required. Inform provider of any chest pain or symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive results may indicate abnormal keratinocyte activity, which can be linked to precancerous changes or early-stage skin cancers. However, further testing (like biopsies) is often needed to confirm a diagnosis. Negative results do not rule out all skin-related issues and may still require additional evaluation.
Short name
CK5/6 & p63 Serum Screening
Frequently asked questions
What does a positive result mean?
Can this test replace a skin biopsy?
How often should I get this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy