IHC Marker-ROS-1 Test: Booking, Price, and Results
About IHC Marker-ROS-1 Test
| Field | Value |
|---|---|
| Also Known As | ROS1 Immunohistochemistry, ROS-1 IHC, ROS1 Protein Expression Test, ROS1 Marker Test |
| Sample Type | Formalin-fixed, paraffin-embedded (FFPE) tumour tissue block (biopsy or surgical specimen) |
| Fasting Required | No—this test is performed on tumour tissue, not blood |
| Report Time | 3 days (confirmatory FISH testing, if required, may take additional time) |
| Recommended For | Individuals with suspected or confirmed non-small cell lung cancer (NSCLC), particularly adenocarcinoma |
| Price | Starting at ₹3,600 |
What is an IHC Marker-ROS-1 Test?
The IHC marker-ROS-1 test detects the presence of the ROS1 protein in tumour tissue using immunohistochemistry (IHC), a laboratory technique that uses antibodies to identify specific proteins in tissue samples. Doctors order this test when a patient has been diagnosed with or is suspected to have non-small cell lung cancer (NSCLC). The test is also known as ROS1 immunohistochemistry or the ROS-1 IHC test. A sample of tumour tissue, preserved in formalin and embedded in paraffin (FFPE block), is used for analysis.
What Does an IHC Marker-ROS-1 Test Measure?
The ROS-1 test examines tumour tissue for three key findings. Together, these help a pathologist determine whether ROS1 gene rearrangement is likely to be present.
| Component | What It Tells Us |
|---|---|
| ROS1 Protein Expression | Whether ROS1 protein is overexpressed in tumour cells, which suggests a possible gene rearrangement |
| Staining Intensity | The pathologist grades how strongly cells stain: 0 (none), 1+ (weak), 2+ (moderate), or 3+ (strong) |
| H-score (Histochemical Score) | A combined score (0 to 300) calculated from staining intensity and the proportion of cells stained; a score of 150 or above suggests a positive result |
Why is an IHC Marker-ROS-1 Test Done?
The ROS-1 IHC test is ordered to find out whether a lung tumour carries a ROS1 gene rearrangement. This information directly guides treatment decisions.
Common Symptoms That May Require This Test
A doctor may order this test after a lung cancer diagnosis is established. The following symptoms often lead to further investigation and eventual testing:
- Persistent cough that does not improve over time
- Coughing up blood or blood-stained mucus
- Chest pain that worsens with deep breathing
- Unexplained weight loss and loss of appetite
- Unusual fatigue or weakness
- Difficulty breathing or shortness of breath
- Swelling in the face or neck
Conditions This Test Can Help Detect
The IHC marker-ROS-1 test is used in the assessment of the following conditions:
- ROS1 gene rearrangements in non-small cell lung cancer (NSCLC)
- ROS1-rearranged lung adenocarcinoma, which is more common in women, non-smokers, and younger patients
- Inflammatory myofibroblastic tumour, a rare soft tissue tumour that may also carry ROS1 rearrangements
- Eligibility for targeted therapy with tyrosine kinase inhibitors (TKIs), which are medicines that block specific signals driving cancer cell growth
How to Prepare and What to Expect
Unlike routine blood tests, the ROS-1 test procedure does not require any physical preparation from the patient. The test is performed on a tissue sample that has already been collected or will be collected by a medical professional.
Do You Need to Fast?
No fasting is required. This test uses a tumour tissue sample, not blood or urine, so diet and fasting do not affect the results.
Practical Tips Before Your Test
- Bring a detailed clinical history, including your symptoms, previous test results, and relevant medical records, as this is required for the test.
- Provide any existing pathology reports along with the tissue specimen.
- Ensure the tissue block submitted has adequate tumour content, as insufficient tumour cells can affect accuracy.
- The tissue must be fixed in 10% neutral buffered formalin and embedded in paraffin (FFPE format); confirm this with the treating doctor or surgeon.
- One representative tumour block is required, though up to four blocks are acceptable.
Step-by-Step Procedure
The ROS-1 test procedure involves tissue collection and laboratory analysis. Here is what happens at each stage:
- A tumour tissue sample is obtained through bronchoscopy (a thin tube with a camera passed into the airways) or surgical removal of the tumour.
- The tissue is preserved in formalin and embedded in paraffin wax to form an FFPE block, which keeps the tissue stable for analysis.
- Very thin slices are cut from the FFPE block and placed on glass slides.
- The slides are treated with specific antibodies (such as the D4D6 or SP384 clone) that bind to the ROS1 protein and produce a visible colour stain.
- A specialist pathologist examines the stained slides under a microscope, assessing how many cells are stained and how intensely.
- The pathologist calculates an H-score and issues a report classifying the result as negative, positive, or equivocal.
Factors That Can Affect Accuracy
Several factors can influence how reliable the test result is:
- Poor tissue fixation or inadequate formalin processing
- Low tumour cell content in the submitted sample
- The specific antibody clone used in the staining process
- Experience of the pathologist interpreting the slides
- Presence of necrotic (dead) tissue in the specimen
- Incorrect specimen handling or storage during transport
Understanding Your IHC Marker-ROS-1 Test Results
Results from the ROS-1 IHC test are reviewed by a pathologist and reported based on staining intensity and H-score. Always discuss your results with your treating oncologist or specialist.
| Result | Finding | Interpretation |
|---|---|---|
| Negative | No staining, weak staining (1+), or low H-score (typically <100) | No significant evidence of ROS1 protein overexpression; ROS1 rearrangement is less likely. |
| Equivocal | Borderline or moderate staining (commonly 2+); H-score approximately 100–149* | Indeterminate result; confirmatory testing with FISH or next-generation sequencing (NGS) is recommended. |
| Positive | Strong staining (typically 3+) and/or high H-score (commonly ≥150*) | Suggests possible ROS1 rearrangement; confirmatory FISH or NGS testing is recommended before treatment decisions are made. |
Disclaimer: 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.
Special Conditions Affecting Results
- Because this is a diagnostic test for cancer, standard healthy levels do not apply. If you have lung cancer risk factors such as a long smoking history or occupational exposure to harmful substances, discuss appropriate screening with your doctor.
- If your result is ROS1-positive, work closely with an oncologist to explore targeted treatment options suited to your situation.
- Follow any screening or monitoring plan recommended by your care team.
Lupin Diagnostics IHC Marker-ROS-1 Test Price
The ROS-1 test cost at Lupin Diagnostics starts at ₹3,600. This test requires a visit to a Lupin Diagnostics centre; home collection is not available, as the sample is a tumour tissue block that must be handled and transported under specific conditions.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 3600 |
| CHENNAI | 3600 |
| HYDERABAD | 3600 |
| KOLKATA | 3600 |
| NAVI MUMBAI | 3600 |
| PUNE | 3600 |
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 your ROS-1 test online or at a centre:
- Select the IHC Marker-ROS-1 test on the Lupin Diagnostics website.
- Choose your city and preferred centre location.
- Visit the centre at your scheduled time and submit the FFPE tumour tissue block along with your clinical history and pathology reports.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Frequently Asked Questions
The IHC marker-ROS-1 test is used to check whether a lung tumour expresses the ROS1 protein, which points to a possible ROS1 gene rearrangement. If confirmed, this finding helps doctors decide whether the patient is likely to respond to ROS1-targeted medicines.
This test is typically recommended for patients diagnosed with non-small cell lung cancer, particularly adenocarcinoma. Studies show it is more commonly relevant for never-smokers, women, and younger adults, though any NSCLC patient may be referred for testing based on their oncologist's guidance.
No. The ROS-1 IHC test is used as a screening step. If the result is positive, confirmatory testing using FISH (fluorescence in situ hybridisation) or NGS (next-generation sequencing) is recommended before any treatment decisions are made. This two-step approach is supported by established pathology guidelines.
The IHC marker-ROS-1 test is considered a sensitive screening method for detecting potential ROS1 rearrangements. Because false-positive results may occur, positive findings should be confirmed using molecular methods such as FISH or NGS.
The standard report time at Lupin Diagnostics is 3 days. If a positive result requires confirmatory FISH or NGS testing, the total turnaround time will be longer. Your doctor will inform you of the expected timeline.
A formalin-fixed, paraffin-embedded (FFPE) tumour tissue block is required. This is usually obtained through a lung biopsy or surgical procedure, not a blood draw. The block must be properly labelled and accompanied by a clinical history and any available pathology reports.
Identifying a ROS1 rearrangement allows doctors to consider targeted therapies specifically designed to block the abnormal signals driving tumour growth. Several approved medicines have shown effectiveness in ROS1-rearranged cancers, making early and accurate testing an important part of the treatment planning process.
IHC Marker-ROS-1 Test
