What's this test for?

This test is ideal if you or your care team are trying to figure out where a tumor originated, especially when colorectal cancer is suspected. It's a specialized tissue stain used alongside other pathology findings to help distinguish a cancer that spread from the colon from cancers that started somewhere else. This test is typically ordered as part of a broader cancer workup rather than a standalone check.

What happens after I get my results?

Your results will be available in your account, with an explanation of what the CDX2 stain result means for the tissue sample tested. Because this is a specialized pathology test, next steps usually involve reviewing the report alongside your other cancer workup results rather than lifestyle changes or retesting on a set schedule. You can download the full lab report from your account at any time, and any related test results can be tracked together over time using the trends feature.

Who should consider this test?

This test is generally considered when a biopsy or surgical tissue sample shows a tumor and there's uncertainty about where the cancer originated. It's most useful for people who already have a tumor sample being evaluated by pathology and need extra clarity on whether it matches a colorectal origin. It is not a general screening test for people without a known tumor finding.

What is CDX2 and why does it matter?

CDX2 is a protein normally found in the cells lining the colon, and pathologists use it as a marker on tissue samples to help figure out where a tumor came from. If a tumor sample stains positive for CDX2, it points toward a colorectal origin, which helps guide diagnosis. This matters because knowing where a cancer started affects how it gets classified and understood in the diagnostic process.

When will I get my results?

Results for this test are typically ready within about 7 days of your sample being processed by the lab. Pathology stains like this one can take a bit longer than routine bloodwork because they involve specialized tissue preparation and microscopic review. You'll be notified as soon as your report is available in your account.

What does a positive CDX2 result mean?

A positive result means the tissue sample shows the CDX2 marker, which supports a colorectal origin for the tumor being evaluated. This is one piece of the puzzle pathologists use alongside other stains and clinical information to reach a full picture. A positive result on its own doesn't diagnose cancer type by itself — it's interpreted together with the rest of the pathology findings.

What does a negative CDX2 result mean?

A negative result means the tissue sample did not show the CDX2 marker, which makes a colorectal origin less likely for that particular tumor sample. Keep in mind that CDX2 expression can sometimes be lost in more advanced colorectal tumors, so a negative result doesn't completely rule out colorectal origin. The report explains this nuance alongside the specific finding for your sample.

What causes an unexpected or unclear CDX2 result?

Sometimes a tumor that started in the colon shows a negative CDX2 result because advanced or less typical tumors can lose this marker over time. On the other hand, some tumors from other body sites, like certain mucinous tumors, can show a positive result even though they didn't start in the colon. This is why the result is always considered alongside other pathology markers rather than on its own.

What should I do if my results are unclear or concerning?

If your report shows a result that raises questions, the best next step is to have it reviewed together with your other pathology and imaging findings for the full picture. Because this test relates to cancer diagnosis, any concerning or unclear results should prompt prompt follow-up rather than waiting. Bring your downloadable lab report to any follow-up appointments so all your results can be compared side by side.

How often should I retest?

This is not a routine or repeat-on-a-schedule test — it's typically run once on a specific tissue sample as part of a cancer diagnosis workup. Retesting would only happen if a new tissue sample is collected, for example from a new biopsy or surgical specimen. Your report will note if any additional pathology work is relevant to your specific sample.

Getting your blood test with us is easy, private & backed by the power of science.Long story short: In the test options, use the filters or search box to narrow your choices and find the test you want. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy! If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

How do I know which test to get?

In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option. Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.

When will my lab results be available?

Most test results will be available within 1–3 business days. Once they're ready, we'll send an email and text message to let you know. After your blood draw, just hang tight and don't worry – we'll keep you updated and in the loop! If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com, and we'll gladly help you.

Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?

Absolutely! We totally understand that errors can happen. No worries, we're here to help you. Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you. There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out. Our lab requires an address to be listed to generate an order.

Do you accept health insurance?

Only HSA & FSA is accepted. Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts. This policy applies to all insurance companies, including federal health insurance programs like Medicare. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

Can I cancel my order?

Yes. We get it – sometimes your needs change. As long as your samples haven’t been collected yet, we’re happy to help you cancel your order. If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com. You can read more about our cancellation policy here.

How can I find a lab location near me?

During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp). Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

CDX2 IHC Test - Colorectal Cancer Origin Marker

Getting your blood test with us is easy, private & backed by the power of science.

Long story short:

In the test options, use the filters or search box to narrow your choices and find the test you want.
If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!

754-799-7833

[email protected]

CDX2 Tumor Marker Test for Colorectal Cancer Origin

CDX2, IHC without Interpretation

Prescription & all lab fees included

Doctor's guidance included

Fast & convenient

Prescription & all lab fees included

Doctor's guidance included

Fast & convenient

What's this test for?

What happens after I get my results?

Who should consider this test?

Here’s why 1,000,000+ customers chose us for affordable hassle-free private blood testing.

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CDX2 Tumor Marker Test for Colorectal Cancer Origin

Prescription & all lab fees included

Doctor's guidance included

Fast & convenient

1,000,000+ blood tests later, here's what our customers say