IHC Marker MLH1 Test: Booking, Price, and Results
About IHC Marker MLH1 Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | MLH1 immunohistochemistry, MLH1 IHC, mutL homolog 1 marker, MLH1 protein expression test |
| Sample Type | Formalin-fixed, paraffin-embedded (FFPE) tumour tissue block |
| Fasting Required | No – tissue is collected during biopsy or surgery, not a routine blood draw. |
| Report Time | 3 Days |
| Recommended For | Patients with colorectal, endometrial, or other Lynch syndrome-associated cancers; those diagnosed under 50 or with a relevant family history |
| Price | Starting at ₹1,920 |
What is an IHC Marker MLH1 Test?
The IHC marker MLH1 test uses a laboratory technique called 'immunohistochemistry' to check whether the MLH1 protein is present in tumour tissue. MLH1 stands for MutL Homolog 1, a protein that helps repair errors in DNA replication. It is also known as MLH1 IHC or mutL homolog 1 marker test. Doctors order this test to understand the behaviour of a tumour and to assess whether a patient may have a hereditary cancer condition called Lynch syndrome. The sample used is a tumour tissue block, either from a fresh biopsy or a previously collected surgical specimen.
What Does an IHC Marker MLH1 Test Measure?
The MLH1 IHC test evaluates tumour tissue for two key findings. The table below explains each.
| Component | What It Measures |
|---|---|
| MLH1 protein expression | Whether the MLH1 protein is present and functioning in tumour cell nuclei. |
| Nuclear staining pattern | Presence or absence of staining in tumour cells, compared against internal tissue controls such as lymphocytes and normal colon lining cells. |
When MLH1 protein is present, tumour cells show nuclear staining. When it is absent, the tumour cells do not stain, while the surrounding normal cells continue to stain (serving as internal positive controls). This difference helps the pathologist determine whether the DNA mismatch repair system is working normally.
Why is an IHC Marker MLH1 Test Done?
This test is ordered in specific clinical situations, particularly when a cancer diagnosis raises questions about hereditary risk or treatment options.
Common Symptoms That May Require This Test
- Unexplained or unintended weight loss.
- Changes in bowel habits lasting more than a few weeks.
- Rectal bleeding or blood in stools.
- Persistent abdominal pain or cramping.
- Anaemia (low red blood cell count) without a clear cause.
- Personal or family history of colorectal or endometrial cancer.
- Cancer diagnosis at a younger age, typically under 50 years.
Conditions This Test Can Help Detect
- Lynch syndrome, a hereditary cancer syndrome that may be suspected when MLH1 protein expression is lost and may require confirmatory genetic testing.
- Deficient mismatch repair (dMMR), a tumour characteristic where DNA repair is not functioning normally.
- Microsatellite instability-high (MSI-H) tumours, which account for roughly 15 to 20 percent of sporadic colorectal cancers and up to 45 percent of sporadic endometrial cancers.
- Tumours that may be considered for treatment with certain immune checkpoint inhibitors, depending on the cancer type and clinical circumstances.
How to Prepare and What to Expect
Since this test is performed on tumour tissue rather than a blood or urine sample, the preparation steps differ from routine diagnostic tests.
Do You Need to Fast?
No fasting is required. The tissue sample is collected during a biopsy or surgical procedure, not through a standard blood draw. Any pre-procedure preparation instructions will be given by your surgeon or treating doctor.
Practical Tips Before Your Test
- Provide relevant clinical information, including previous test results, cancer history, and family history, as this may assist with interpretation.
- Inform your doctor about any recent cancer treatments, such as chemotherapy, radiotherapy, or targeted therapies, as these may affect tissue quality and interpretation.
- If a tissue block from a previous biopsy or surgery is available, check with your doctor whether it can be used for this test.
- Ensure your treating doctor has shared relevant medical records with the laboratory.
Step-by-Step Procedure
- A tumour tissue sample is collected by your surgeon or interventional specialist during a biopsy or surgical procedure.
- The tissue is placed in formalin solution and fixed for the appropriate duration, then embedded in paraffin wax to create a tissue block.
- Thin sections of the tissue block are cut and mounted on specially coated glass slides in the laboratory.
- The slides are treated with specific antibodies that bind to the MLH1 protein if it is present in the tissue.
- A staining agent makes the bound antibodies visible under a microscope. The pathologist then examines the staining pattern in tumour cells against the internal tissue controls.
- The pathologist prepares a report, and results are delivered within 3 days.
Factors That Can Affect Accuracy
Several factors can influence the accuracy of the test:
- Inadequate formalin fixation time (the recommended window is 6 to 48 hours).
- Insufficient tumour tissue in the sample (at least 20 percent tumour nuclei are needed).
- Gene mutations or MLH1 gene methylation, which can independently affect protein levels.
- The specific antibody clone used in the staining process.
- Tissue handling and storage conditions prior to processing.
Understanding Your IHC Marker MLH1 Test Results
Your results will describe the MLH1 protein expression in your tumour tissue as either intact (positive) or lost (negative). Below is a general guide to what each finding means.
| Result | Expression status | Interpretation |
|---|---|---|
| Positive (intact) | Nuclear staining present in tumour cells | Mismatch repair proficient (pMMR); Lynch syndrome unlikely. |
| Negative (lost) | Nuclear staining absent in tumour cells; internal controls positive | Mismatch repair deficient (dMMR); further testing recommended. |
Loss of MLH1 expression often occurs together with loss of PMS2, because the two proteins work as a pair. When MLH1 is absent, PMS2 loses its binding partner and is also lost. This pattern helps guide the next steps in testing.
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
The accuracy of MLH1 immunohistochemistry (IHC) can be influenced by both technical and biological factors. Although MMR IHC is highly reliable, false-negative and false-positive results can occasionally occur.
In some cases, an unusual dot-like nuclear staining pattern seen with a particular antibody clone may represent a technical artefact rather than true protein expression. Repeating the test with a different antibody clone can help clarify the finding.
Inadequate tissue fixation, poor tissue preservation, and other pre-analytical factors may also affect staining quality and make interpretation more challenging.
How to Maintain Healthy Levels
Because this test is an oncology marker rather than a routine health check, the following tips relate to general cancer awareness and risk reduction:
- Attend recommended cancer screening and follow-up appointments, particularly if you have a personal or family history of cancer.
- Discuss your family history of cancer with your healthcare provider to determine whether genetic counselling or further testing may be appropriate.
- Follow your doctor's advice regarding cancer surveillance, treatment, and ongoing monitoring.
- Maintain a healthy lifestyle by avoiding tobacco, eating a balanced diet, staying physically active, and maintaining a healthy weight, which may help reduce the overall risk of certain cancers.
Lupin Diagnostics IHC Marker MLH1 Test Price
The IHC MLH1 test cost at Lupin Diagnostics starts at ₹1,920. This test requires a visit to a Lupin Diagnostics centre; home collection is not available for this test, as it is performed on a tissue block rather than a blood or urine sample.
| 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
The following steps explain how to book the IHC marker MLH1 test online:
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred centre location.
- Visit the centre at your scheduled time for sample submission.
- Receive your report via email or WhatsApp within 3 days.
Frequently Asked Questions
The IHC MLH1 test is used to evaluate tumour tissue for loss of the MLH1 protein, which helps identify tumours that may be associated with Lynch Syndrome, and may require further testing to determine the underlying cause. a hereditary cancer condition. It also helps determine whether a tumour is mismatch repair deficient, which has implications for treatment planning, including immunotherapy eligibility.
The test requires a tumour tissue block, not a blood or urine sample. The tissue is typically obtained during a biopsy or surgical procedure. If a tissue block from a previous procedure is already available, it may sometimes be used after discussion with your doctor.
No. Loss of MLH1 expression on IHC does not confirm Lynch syndrome on its own. Loss of MLH1 expression can also occur in sporadic (non-hereditary) tumours due to a process called MLH1 promoter hypermethylation. Additional tests are needed to determine whether the loss is hereditary or sporadic.
The MLH1 gene plays a key role in repairing DNA copying errors. When it is not functioning, errors accumulate in tumour DNA, raising cancer risk. In people with lynch syndrome caused by MLH1 gene variants, the estimated risk of developing cancer by age 70 is between 65 and 80 percent.
The procedure itself is carried out entirely in the laboratory on a tissue sample, so it does not directly cause any discomfort. Any pain or discomfort is related to the biopsy or surgical procedure used to collect the tissue, which your treating doctor will explain separately.
The MMR proteins work in pairs: MLH1 pairs with PMS2, and MSH2 pairs with MSH6. Testing all four proteins together gives the pathologist a clearer picture of which part of the repair system has failed. This pattern of protein loss also helps direct further genetic testing in a targeted and efficient way.
IHC Marker MLH1 Test: Booking, Price, and Results
