IHC Marker - Factor XIIIa Test
About IHC Marker - Factor XIIIa Test
| Field | Value |
|---|---|
| Also Known As | Factor XIII Subunit A, F13a, Fibrin Stabilising Factor, FXIIIa IHC, Factor 13a Immunostain |
| Sample Type | Tissue sample (formalin-fixed, paraffin-embedded block) |
| Fasting Required | No. This test is performed on tissue, not blood |
| Report Time | 3 days |
| Recommended For | All genders and ages when clinically indicated |
| Price | Starting at ₹1,920 |
What is an IHC Marker - Factor XIIIa Test?
The IHC marker - Factor XIIIa test is an immunohistochemistry (IHC) test, meaning it uses a special staining technique on tissue samples to detect a specific protein. Factor XIIIa, also called fibrin stabilising factor, is a protein found in certain skin immune cells known as dermal dendrocytes. Pathologists use this test to identify and classify different types of skin tumours. It is also known as the Factor 13a Immunostain or FXIIIa IHC.
What Does an IHC Marker - Factor XIIIa Test Measure?
This test detects the presence or absence of Factor XIIIa protein within tissue cells. The table below explains what the test looks for and why it matters.
| Component | What It Tells Us |
|---|---|
| Factor XIIIa protein expression | Identifies dermal dendrocytes, fibroblasts, and histiocytic cells within the tissue |
| Cytoplasmic staining pattern | Confirms whether tumour cells contain Factor XIIIa, helping to classify the lesion type |
| Reactivity with anti-Factor XIIIa antibody | Distinguishes benign fibrohistiocytic lesions from malignant spindle cell tumours |
Factor XIIIa acts as a transglutaminase, an enzyme that cross-links proteins to stabilise blood clots. In diagnostic pathology, its expression pattern in tissue helps separate one type of tumour from another.
Why is an IHC Marker - Factor XIIIa Test Done?
This test is ordered when a tissue biopsy result is unclear or when a pathologist needs additional information to classify a skin lesion accurately.
Common Symptoms That May Require This Test
A clinician may request this test after a biopsy is taken from a patient presenting with any of the following:
- A slowly enlarging, firm, skin-coloured or brownish nodule on the skin
- A suspicious skin lump or mass requiring further characterisation
- A fibrohistiocytic skin lesion identified on initial biopsy
- An unclear or inconclusive histopathology result needing additional markers
- A skin lesion that needs to be confirmed as benign or potentially malignant
Conditions This Test Can Help Detect
The IHC marker - Factor XIIIa test helps pathologists differentiate between several conditions, including:
- Dermatofibroma (a common benign skin tumour, typically Factor XIIIa positive)
- Dermatofibrosarcoma protuberans (DFSP), a malignant skin tumour that is typically Factor XIIIa negative
- Sebaceous neoplasms, including sebaceous carcinoma (a rare cancer arising from oil glands)
- Capillary haemangioma (a benign blood vessel tumour)
- Other fibrohistiocytic or spindle cell lesions of the skin and soft tissue
- Certain central nervous system tumours and vascular tumours
How to Prepare and What to Expect
Because this is a tissue-based test, preparation differs from that for a standard blood test. Here is what you need to know before and during the process.
Do You Need to Fast?
No fasting is required. This IHC marker - Factor XIIIa test is performed on a tissue sample, not a blood sample, so dietary restrictions do not apply.
Practical Tips Before Your Test
Keep the following points in mind before submitting your tissue sample:
- Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test
- The tissue biopsy must be performed by a dermatologist or surgeon before this IHC test can be carried out
- Inform your doctor and pathologist of any suspected diagnosis, as this aids in accurate interpretation
- Ensure the tissue is fixed in 10% neutral buffered formalin; using other fixatives may affect the result
- Ask your clinician to confirm that the FFPE tissue block or unstained slides are packaged and labelled correctly before submission
Step-by-Step Procedure
The IHC marker - Factor XIIIa test procedure involves the following steps:
- A clinician (dermatologist or surgeon) performs a skin biopsy to obtain a tissue sample using a punch, excision, or core biopsy technique.
- The tissue is preserved (fixed) in formalin to prevent degradation, then embedded in paraffin wax to create a solid block.
- Thin slices of this formalin-fixed, paraffin-embedded (FFPE) tissue block are cut at approximately 4-5 microns and mounted on glass slides.
- The slides are stained in the laboratory with an anti-Factor XIIIa antibody, which binds to the protein when present in the tissue.
- A qualified pathologist examines the stained slides under a microscope and records the staining pattern.
- The pathologist interprets the result alongside clinical history, other IHC markers, and the tissue's appearance to arrive at a diagnosis.
Factors That Can Affect Accuracy
The following factors may influence the reliability of the result:
- Formalin fixation time (recommended: 6 to 72 hours; under- or over-fixation can affect staining)
- Overall quality of tissue preservation before the block is prepared
- Use of the correct antibody clone in the laboratory
- Pathologist's expertise in interpreting IHC staining patterns
- Inclusion of appropriate positive and negative control tissues during testing
Understanding Your IHC Marker - Factor XIIIa Test Results
Results for this test are reported as positive or negative and must always be reviewed by a qualified pathologist alongside other clinical and laboratory findings.
| Result | Typical Interpretation |
|---|---|
| Positive | Factor XIIIa protein detected; supports fibrohistiocytic origin (e.g., dermatofibroma) |
| Negative | Factor XIIIa protein not detected; may suggest DFSP or another spindle cell tumour |
| Tumour Type | Factor XIIIa | CD34 |
|---|---|---|
| Dermatofibroma (DF) | Positive (seen in approximately 97% of cases) | Usually negative |
| Dermatofibrosarcoma protuberans (DFSP) | Negative | Positive |
"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."
Results During Special Conditions
Certain situations can make results harder to interpret. A pathologist will account for these when reporting:
- Some dermatofibromas may show weak or absent Factor XIIIa staining, and some DFSP cases may show focal positivity due to normal dermal dendrocytes trapped within the tumour tissue.
- In inflammatory skin conditions such as atopic eczema and psoriasis, an increased number of Factor XIIIa-positive cells may be seen in the upper layer of the skin, which can complicate interpretation.
How to Maintain Healthy Levels
Factor XIIIa is a diagnostic tissue marker, not a health parameter that can be optimised through lifestyle changes. However, the following general habits support skin health:
- Perform regular skin self-examinations and promptly report any new or changing lesions to a dermatologist.
- Attend periodic skin check-ups if you have a personal or family history of skin tumours.
- Protect your skin from excessive sun exposure, which is a known risk factor for several skin conditions.
Lupin Diagnostics IHC Marker - Factor XIIIa Test Price
The IHC marker - Factor XIIIa test cost at Lupin Diagnostics starts at ₹1,920. This test requires a visit to a Lupin Diagnostics centre; home collection is not available, as it is performed on a tissue block submitted by your clinician or surgeon.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 1920 |
| CHENNAI | 1920 |
| HYDERABAD | 1920 |
| KOLKATA | 1920 |
| NAVI MUMBAI | 1920 |
| PUNE | 1920 |
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 your IHC marker - Factor XIIIa 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 FFPE tissue block or unstained slides.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Frequently Asked Questions
The IHC marker - Factor XIIIa test is an immunohistochemistry test performed on a tissue sample. It detects the Factor XIIIa protein, which is present in specific immune cells in the skin. Pathologists use the results to accurately identify and classify skin tumours.
Your doctor has likely ordered this test to determine whether a skin lesion is benign or potentially malignant. Distinguishing between a dermatofibroma (benign) and dermatofibrosarcoma protuberans (malignant) often requires this type of specialised staining.
The tissue sample is collected through a skin biopsy performed by a dermatologist or surgeon before the IHC test is carried out. There is no separate sample collection at the diagnostic lab; you simply submit the prepared tissue block.
The IHC test is performed entirely in the laboratory on your tissue sample. The biopsy procedure that provides the tissue may involve local anaesthesia and minor discomfort, but the IHC testing process requires nothing further from you.
A positive result indicates that Factor XIIIa protein is present in the tissue, which often supports a diagnosis of a benign fibrohistiocytic lesion such as dermatofibroma. However, the result must always be interpreted by a pathologist alongside other markers and clinical details.
No single IHC marker provides a definitive diagnosis. The IHC marker - Factor XIIIa test is typically used alongside CD34 and other markers. A pathologist interprets all findings, along with the microscopic appearance of the tissue, to reach a final conclusion.
Results for the IHC marker - Factor XIIIa test are typically available within 3 days. Turnaround time may vary slightly depending on whether additional stains or repeat testing are required.
IHC Marker - Factor XIIIa Test
