Home TestIhc Marker Cdx2 Test

IHC Marker - CDX2 Test

About IHC Marker - CDX2 Test

Field	Value
Also Known As	CDX2 IHC, CDX2 Immunostain, Caudal-Type Homeobox 2, CDX2 Marker Test
Sample Type	Formalin-fixed, paraffin-embedded (FFPE) tissue block
Fasting Required	No — this test is performed on preserved tissue samples, not blood or urine
Report Time	3 days
Recommended For	All genders and ages; patients with suspected gastrointestinal cancers or metastatic tumours of unknown origin
Price	Starting at ₹1,920

What is an IHC Marker - CDX2 Test?

The CDX2 test is a specialised immunohistochemistry (IHC) test that detects the presence of the CDX2 protein in preserved tissue samples. CDX2 (Caudal-Type Homeobox 2) is a protein that controls the growth and maturation of cells lining the intestine. Pathologists use this test to determine whether a tumour has originated from the intestines, particularly when the source of a cancer is not immediately clear. It is also known as the CDX2 IHC or CDX2 immunostain.

What Does an IHC Marker - CDX2 Test Measure?

The CDX2 marker test analyses preserved tumour tissue for the presence of CDX2 protein within cell nuclei. Here is what the test evaluates:

Parameter	What It Means
Positive (nuclear staining)	CDX2 protein detected; suggests the tumour has an intestinal origin
Negative	CDX2 protein absent; points away from intestinal origin or may indicate a poorly differentiated tumour
Weak or Focal	Variable protein expression; additional markers may be needed to confirm origin

Why is an IHC Marker - CDX2 Test Done?

A doctor may order the CDX2 test when tumour tissue needs to be assessed for intestinal origin. The sections below outline typical reasons for this test.

Common Symptoms That May Require This Test

The following symptoms may prompt a doctor to request this test:

Unexplained weight loss
Persistent abdominal pain
Change in bowel habits
Blood in stool
A palpable (felt by touch) abdominal mass
Metastatic tumours detected on imaging scans
Persistent fatigue with no clear cause

Conditions This Test Can Help Detect

This test can help identify or rule out several conditions:

Colorectal cancer (CDX2 is expressed in a large majority of colorectal cancer cases)
Metastatic colorectal carcinoma (cancer that has spread from the colon or rectum)
Intestinal metaplasia of the stomach (abnormal intestinal-type cells found in the stomach lining)
Neuroendocrine tumours of the midgut, such as those arising from the ileum or appendix
Cancer of unknown primary (CUP), where the original source of a metastatic tumour is unclear

How to Prepare and What to Expect

The CDX2 test procedure is performed on tissue that has already been collected and preserved. No preparation is required from the patient when submitting the sample to the laboratory.

Do You Need to Fast?

No fasting is required. This test is performed on a tissue block that was obtained during a prior biopsy, not on a blood or urine sample collected at the time of testing.

Practical Tips Before Your Test

Keep the following points in mind before submitting your sample:

Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test.
Carry prior imaging reports (such as CT scans or MRI results) to assist the pathologist with interpretation.
Ensure the tissue block or slides are protected from excessive heat during transport.
If you have undergone chemotherapy or radiotherapy recently, inform your doctor, as this can affect protein expression in the tissue.

Step-by-Step Procedure

The CDX2 test procedure involves several steps before and during laboratory analysis:

A tissue sample is collected during a biopsy performed at a hospital or clinic. This may be done via colonoscopy, endoscopy, surgical resection, or needle biopsy.
The collected tissue is fixed in formalin (a preservative solution) and then embedded in paraffin wax to create an FFPE tissue block.
The tissue block is sent to the laboratory, where it is sliced into very thin sections using a precision instrument called a microtome.
The thin sections are mounted onto glass slides and treated to unmask proteins within the tissue cells.
CDX2-specific antibodies are applied to the slide. If CDX2 protein is present, it binds to these antibodies, producing a visible brown stain in the cell nuclei.
A qualified pathologist examines the stained slide under a microscope and prepares a report with findings.

Factors That Can Affect Accuracy

Several factors may influence the reliability of results:

Poor tissue fixation (improper preservation at the time of biopsy)
Delays between biopsy collection and formalin fixation
Prior chemotherapy or radiotherapy, which can alter protein expression in tumour cells
Older tissue blocks or sections, as paraffin sections older than six weeks may show reduced immunoreactivity
The type and grade of the tumour, since poorly differentiated tumours may show weaker staining

Understanding Your IHC Marker - CDX2 Test Results

Your CDX2 test results are reported by a pathologist and should always be reviewed alongside your clinical history, imaging findings, and other laboratory tests. The table below summarises what different results may indicate:

Result	Possible Interpretation
Positive	Supports intestinal or colorectal origin; seen in colorectal adenocarcinomas, midgut neuroendocrine tumours, some gastric and pancreatic tumours, and bladder adenocarcinomas
Negative	Argues against intestinal origin; CDX2 is not expressed in liver, kidney, breast, lung, or salivary gland cancers
Weak or Focal	Inconclusive on its own; further IHC markers may be needed

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 clinical factors can influence how CDX2 results are interpreted:

Loss of CDX2 expression is associated with more advanced colorectal cancer, poor tumour differentiation, and the presence of lymphovascular invasion (cancer spreading into nearby lymph or blood vessels). These cases may reflect a more aggressive disease course.
In colorectal cancers with the BRAF V600E gene mutation, CDX2 expression tends to be lower. Loss of CDX2 in this setting has been linked to poorer survival outcomes.
CDX2 staining may occasionally appear in prostate or thyroid cancers and certain gynaecological lesions unrelated to intestinal differentiation. These are known diagnostic pitfalls that a pathologist will account for.

How to Maintain Healthy Levels

While CDX2 is a diagnostic marker and not a value to "maintain," the following habits support digestive health in general:

Include fibre-rich foods, fruits, and vegetables in your daily diet to support gut health.
Follow your doctor's advice on colorectal cancer screening, especially if you are above 45 years of age or have a family history of colorectal cancer.
Avoid tobacco use and limit alcohol intake, as both are associated with an increased risk of gastrointestinal cancers.

Lupin Diagnostics IHC Marker - CDX2 Test Price

The CDX2 test cost at Lupin Diagnostics starts at ₹1,920. This test requires a visit to a Lupin Diagnostics centre or partner facility, as home collection is not available for tissue biopsy specimens.

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 for the CDX2 test online booking with Lupin Diagnostics:

Select the IHC Marker - CDX2 Test on the Lupin Diagnostics website.
Choose your city and preferred centre location.
Visit the centre at your scheduled time to submit the FFPE tissue block or slides.
Receive your report via email or WhatsApp within 3 days of specimen receipt.

Frequently Asked Questions

The CDX2 test helps pathologists determine whether a tumour originated in the intestines. It is most commonly used when a metastatic tumour is found and the primary source is not known. It is one of the most sensitive markers for identifying colorectal and other intestinal cancers.

The sample is a formalin-fixed, paraffin-embedded (FFPE) tissue block. This tissue is obtained through a biopsy performed before the test, using methods such as colonoscopy, endoscopy, or surgical resection. No additional sample collection is needed at the time of submission to the laboratory.

Not necessarily. A positive result supports intestinal origin but can also be seen in neuroendocrine tumours, some gastric and pancreatic tumours, and bladder adenocarcinomas. The CDX2 IHC result must always be interpreted as part of a broader panel of markers and in context with clinical findings.

No. The CDX2 test home collection option is not available because this test requires a tissue biopsy specimen processed in a specialised histopathology laboratory. The biopsy procedure must be performed at a hospital or clinic.

Lupin Diagnostics delivers the report within 3 days of receiving the specimen. Turnaround time may vary slightly depending on the completeness of the clinical history provided with the sample.

Yes. CDX2 is routinely used as part of an IHC panel. It is often tested together with CK7, CK20, and SATB2 to help identify or rule out a gastrointestinal source in carcinomas of unknown primary. Your pathologist will determine which combination of markers is most appropriate.