What's this test for?

This test is ideal if you've been diagnosed with colorectal or endometrial cancer and your care team wants to check whether the tumor tissue is missing a key DNA repair protein called MLH1. Loss of this protein can point to Lynch syndrome, an inherited condition that raises the risk of certain cancers. It's also useful if you have a strong family history of colorectal or endometrial cancer and want to understand whether an inherited cause might be involved.

What's included in this test?

This test looks specifically at the MLH1 protein using a technique called immunohistochemistry, which stains tumor tissue to see if the protein is present or missing. MLH1 is one of four DNA mismatch repair proteins that normally fix errors when your cells copy DNA; when it's missing, that can be a sign of Lynch syndrome or a separate sporadic (non-inherited) tumor process. This information helps guide further testing and treatment planning for colorectal or endometrial cancer.

What happens after I get my results?

Your results will be available in your account, with an explanation of what a normal (intact) versus abnormal (lost) MLH1 expression result means. If MLH1 expression is lost, a common next step is additional tissue testing (such as BRAF mutation or MLH1 promoter methylation testing) before considering germline genetic testing for Lynch syndrome. The standard lab report can be downloaded directly from your account, and if you undergo repeat or related testing over time, you can track those results using the trends feature.

How can I naturally support DNA repair and overall cellular health?

While no natural approach can replace or fix a missing MLH1 protein, general habits that support healthy cells include eating a diet rich in vegetables, fruits, and fiber, limiting processed and red meat, staying physically active, and avoiding tobacco and excess alcohol. These habits are especially relevant for people with Lynch syndrome or a family history of colorectal or endometrial cancer, since they may help lower overall cancer risk alongside recommended screening. This test result should guide any decisions about increased or earlier cancer screening.

When will I get my results?

Results from this MLH1 IHC test are typically ready within about 7 days after your tissue sample is processed at the lab. You'll be notified as soon as your report is available in your account, where you can view and download it.

Who should consider this test?

This test is most relevant for people recently diagnosed with colorectal or endometrial cancer, since screening tumor tissue for MMR protein loss is now a standard part of evaluating these cancers. It's also worth considering if you have a personal or family history that suggests Lynch syndrome, such as multiple relatives with colorectal, endometrial, or related cancers at a young age. Discussing your family history and cancer diagnosis can help determine if this test fits your situation.

What does it mean if my MLH1 result shows loss of expression?

Loss of MLH1 expression means the tumor cells are not making this DNA repair protein, which can happen for two main reasons: an inherited mutation in the MLH1 gene (Lynch syndrome) or a non-inherited process called promoter methylation, often linked to a BRAF gene mutation. Additional tissue tests can help tell these two possibilities apart before moving on to genetic testing. This result does not mean cancer will definitely return, but it does affect screening and treatment planning going forward.

What causes loss of MLH1 expression in tumor tissue?

MLH1 loss is usually caused by either an inherited (germline) mutation in the MLH1 gene, which runs in families with Lynch syndrome, or by a sporadic process where the MLH1 gene gets silenced through a chemical change called promoter methylation, often paired with a BRAF mutation. Telling these apart matters because only the inherited form affects family members and future cancer risk planning. Follow-up tissue testing is typically used to figure out which cause applies to your case.

How often should I retest?

MLH1 IHC testing is generally done once on the original tumor tissue at diagnosis, not on a repeat schedule like a blood test. If a new tumor develops or additional tissue becomes available, retesting may be considered based on your specific situation. Any future related testing, such as germline genetic testing, would be a separate, one-time evaluation rather than a routine recheck.

What should I do if my results show abnormal MLH1 expression?

If your results show loss of MLH1 expression, a reasonable next step is pursuing additional tissue-based testing (like BRAF mutation or promoter methylation analysis) to help clarify the cause. Depending on those results and your family history, germline genetic testing for Lynch syndrome may be a helpful next step. Sharing your full family cancer history alongside this result can help put the finding into proper context.

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.

MLH1 IHC Test - Lynch Syndrome Tumor Screening

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]

MLH1 IHC Test — Lynch Syndrome Cancer Screening

MLH1, IHC with 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's included in this test?

What happens after I get my results?

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MLH1 IHC Test — Lynch Syndrome Cancer Screening

Prescription & all lab fees included

Doctor's guidance included

Fast & convenient

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