IHC Marker-CK5/6 Test
About IHC Marker-CK5/6 Test
| Field | Value |
|---|---|
| Also Known As | Cytokeratin 5/6, CK 5/6, CK5/6 IHC, Cytokeratin 5 and 6 Immunohistochemistry |
| Sample Type | Formalin-fixed, paraffin-embedded (FFPE) tissue block |
| Fasting Required | No |
| Report Time | 7 days |
| Recommended For | All genders and ages; used primarily in cancer diagnosis |
| Price | Starting at ₹1,920 |
What Is an IHC Marker-CK5/6 Test?
The IHC Marker-CK5/6 Test is a specialised laboratory test that detects the presence of cytokeratin 5 and 6 proteins in a tissue sample. These proteins are found in the structural framework of certain epithelial cells, which are the lining cells of organs and skin. Also known as Cytokeratin 5/6 or CK5/6 IHC, this test is ordered by doctors when they need to identify the type or origin of a tumour. The sample used is a formalin-fixed, paraffin-embedded (FFPE) tissue block obtained from a biopsy or surgical procedure.
What Does an IHC Marker-CK5/6 Test Measure?
The test detects specific proteins in tumour tissue using a technique called immunohistochemistry (IHC), which uses antibodies to reveal the presence of target molecules in cells.
The following are the key markers assessed:
| Marker | What It Tells Us |
|---|---|
| Cytokeratin 5/6 (CK5/6) | Intermediate filament proteins in the cytoskeleton of epithelial cells indicate squamous or basal cell origin |
| Basal cell expression | Confirms whether tumour cells share features with the basal layer of the skin or epithelium |
| Staining intensity | Scored from 0 (no staining) to 3 (intense staining) to quantify protein expression |
| Staining quantity | Scored from 0 (no cells stained) to 4 (81% to 100% of cells stained) |
A result is generally considered positive when cytoplasmic staining is seen in more than 10% of invasive tumour cells.
Why Is an IHC Marker-CK5/6 Test Done?
Doctors order this test to help classify tumours and distinguish between different cancer types that may look similar under a microscope.
Common Symptoms That May Require This Test
A doctor may request this test after a biopsy is performed to investigate the following:
- An unexplained lump or mass discovered on examination or imaging
- Persistent cough or difficulty breathing not explained by infection
- Chest pain that does not respond to standard treatment
- Unexplained weight loss alongside other concerning symptoms
- Abnormal findings on a scan or X-ray
- Suspected spread of cancer from another part of the body
Conditions This Test Can Help Detect
The CK5/6 IHC test is used to help identify or rule out several tumour types. These include:
- Squamous cell carcinoma (cancer arising from squamous cells in organs such as the lungs, skin, or oesophagus)
- Mesothelioma (cancer of the lining of the lungs or abdomen)
- Transitional cell carcinoma (a type of bladder cancer)
- Basal cell carcinoma
- Basal-like triple-negative breast carcinoma
- Thymoma (tumour of the thymus gland)
- Salivary gland tumours
How to Prepare and What to Expect
No special preparation is needed from the patient for this test. The tissue sample is collected during a biopsy or surgical procedure arranged by your healthcare team.
Do You Need to Fast?
No fasting is required for this test. There are no dietary restrictions before or after the procedure.
Practical Tips Before Your Test
Here are a few things to keep in mind before your sample is submitted for analysis:
- Bring a detailed clinical history, including your symptoms, previous test results, and any relevant medical records, as this is required for the test
- Inform your doctor about all medications you are currently taking
- Follow all pre-biopsy instructions provided by your treating doctor or surgeon
- The tissue sample is usually already collected before the IHC marker-CK5/6 test is ordered
Step-by-Step Procedure
The process from sample collection to result involves the following steps:
- A biopsy or surgical procedure is performed by a doctor to remove a small piece of tissue from the affected area.
- The tissue is preserved using formalin and embedded in a paraffin wax block, creating an FFPE tissue block that is sent to the laboratory.
- In the laboratory, thin sections of the tissue are cut and placed on glass slides.
- A primary antibody that specifically binds to CK5/6 proteins is applied to the tissue section.
- A secondary antibody linked to a colour-producing enzyme is added; if CK5/6 is present, the tissue changes colour in those areas.
- A pathologist examines the staining pattern and intensity under a microscope and prepares the final report.
Factors That Can Affect Accuracy
Several factors can influence how reliable the test results are. These include:
- Quality of the tissue sample and how well it was preserved
- Proper fixation and processing of the FFPE block before submission
- Quality of the antibodies used in the staining process
- Experience of the pathologist interpreting the results
- Use of appropriate positive and negative controls during the staining procedure
Understanding Your IHC Marker-CK5/6 Test Results
Results are reported as positive or negative, accompanied by a scoring assessment. They must always be reviewed by a qualified pathologist and your treating doctor in the context of your full clinical picture.
| Result | Interpretation |
|---|---|
| Positive | CK5/6 proteins are present in the tumour cells, suggesting a squamous cell, basal cell, or mesothelial origin |
| Negative | CK5/6 proteins are absent; may point towards a non-squamous tumour origin such as adenocarcinoma or certain other cancers |
Disclaimer: These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
A positive result may be seen in squamous cell carcinomas, mesothelioma (positive in approximately 83% of epithelioid cases), basal-like breast carcinomas, thymoma, and transitional cell carcinomas. A negative result is typical for tumours such as lung adenocarcinoma, colon adenocarcinoma, renal cell carcinoma, thyroid tumours, and small cell carcinoma.
Results During Special Conditions
Certain circumstances can affect how results are read:
- Patients with the p230 transcript and neutrophilic CML typically follow an indolent (slow-moving) course, likely because p230 mRNA and protein levels are naturally lower.
- A negative or undetectable result does not entirely rule out the presence of BCR-ABL1 transcripts below the detection limit of the assay, or rare transcript types not covered by the test.
- RNA degradation due to improper sample handling can produce a falsely low or undetectable result.
How to Maintain Healthy Levels
CK5/6 is a tissue-based diagnostic marker and is not influenced by lifestyle factors such as diet or exercise. The following general points may, however, support your overall cancer care:
- Attend all follow-up appointments recommended by your oncologist
- Undergo regular cancer screening as advised by your doctor, especially if you have a family history of cancer
- Discuss any concerns about your diagnosis or results openly with your treating specialist
Lupin Diagnostics IHC Marker-CK5/6 Test Price
The IHC marker-CK5/6 test cost at Lupin Diagnostics starts at ₹1,920. This test requires a visit to a Lupin Diagnostics centre or submission of a pre-collected tissue block; home collection is not available for this test.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 1920 |
| CHENNAI | 1920 |
| HYDERABAD | 1920 |
| KOLKATA | 1920 |
| NAVI MUMBAI | 1920 |
| PUNE | 1920 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
Follow these steps to book the IHC marker-CK5/6 test online or at a centre:
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred centre location.
- Visit the centre at your scheduled time to submit your tissue block or slides.
- Receive your report via email or WhatsApp within 7 days.
Frequently Asked Questions
This test detects the presence of cytokeratin 5 and 6 proteins in a tumour tissue sample. Pathologists use it to identify the type of tumour and distinguish between cancer types that may appear similar under a microscope, such as squamous cell carcinoma and adenocarcinoma.
The test itself is performed on a tissue sample in the laboratory and does not involve any discomfort. Any pain or discomfort would be related to the biopsy or surgical procedure used to collect the tissue, not the laboratory analysis.
The turnaround time at Lupin Diagnostics is 7 days. This accounts for the time needed to process the tissue block, perform the staining, and have the results interpreted by a pathologist.
The test is particularly useful in identifying squamous cell carcinomas, mesothelioma, basal-like breast carcinomas, transitional cell carcinomas, thymoma, and salivary gland tumours. It also helps rule out certain cancer types that do not express CK5/6.
No. CK5/6 is typically used as part of a panel of IHC markers rather than as a standalone test. A pathologist uses the results alongside other markers, clinical details, and imaging findings to reach a diagnosis.
A positive CK5/6 result in breast cancer often indicates a basal-like subtype of triple-negative breast carcinoma, which lacks the common hormone receptors. These tumours are generally high-grade with a high rate of cell division. Your oncologist will discuss what this means for your specific situation.
The pathologist interpreting the IHC Marker-CK5/6 test needs your clinical background, including symptoms, previous diagnoses, and imaging results, to provide an accurate and meaningful report. Without this context, the staining pattern cannot be interpreted correctly.
IHC Marker-CK5/6 Test
