1800 202 8726
Reading your histopathology report

Immunohistochemistry on Your Report — What IHC Actually Tests

Your histopathology report may arrive with extra pages of IHC results and marker names your oncologist has not yet explained. This page says what those terms mean — not what they mean for your specific result, which is a conversation for your doctor.

Medically reviewed by Dr. C. Raghavendra Reddy, Medical Oncologist, MBBS (Gold Medal) · DNB · DM (Medical Oncology, Gold Medal) · Last reviewed September 2026

  • A protein test added to the microscope exam — IHC uses antibodies to find specific proteins in your tumour tissue.
  • Ordered when the basic exam needs more — Your pathologist adds it to identify the cancer type, subtype it, or check for proteins that affect treatment.
  • Results as positive or negative — Each marker comes back as detected or not detected, sometimes with a score or staining intensity.
  • Interpreted by your oncologist, not in isolation — What a positive or negative means depends entirely on which marker and which cancer type.
4.8 · 800+ Google reviews · 15,000+ patients treated
Limited Slots Today

Get this explained properly

₹950   Today: FREE  ·  Including free written second opinion

Reply within 2 working hours
Report reviewed by a senior oncologist
Confidential. No commitment to start treatment.
or
Call 1800 202 8726
17+
Cancer Specialists
on Panel
96.9%
Breast Cancer
Survival Rate*
15,000+
Patients
Treated
4.8★
Google Rating
(800+ reviews)

Immunohistochemistry (IHC) is a laboratory test that uses antibodies to detect specific proteins in your tumour tissue. Your pathologist ordered it to help identify the cancer type, subtype it accurately, or check for proteins that guide treatment. The results appear as positive or negative for each marker tested.

What do the terms in an IHC report mean?

Immunohistochemistry (IHC)
A laboratory test performed on a thin slice of your biopsy tissue. The pathologist applies antibodies to the tissue to detect whether specific proteins are present, then examines the result under a microscope.
Antibody
A protein engineered in the laboratory to bind to one specific target. Each antibody the pathologist uses tests for one marker only.
Marker or biomarker
The protein being tested for. Each marker has a name — such as ER, PR, HER2, Ki-67, CK5/6, or PD-L1 — and what it means depends on your cancer type.
Positive
The protein was found in the tissue. Whether that is relevant to your treatment depends on which marker it is and what cancer you have — your oncologist will explain what it means for you.
Negative
The protein was not detected. The meaning depends on the specific marker and the clinical context, in the same way that positive does.
Staining intensity
How strongly the marker showed up — often recorded as weak, moderate, or strong, sometimes as a numerical score. Your pathologist weighs this alongside the proportion of cells that showed it.
Ki-67
A marker that reflects how quickly cells are dividing. It is reported as a percentage, which your oncologist interprets alongside other findings — not as a standalone number.

How is IHC different from the rest of the pathology report?

FeatureRoutine pathology (H&E stain)Immunohistochemistry (IHC)
What it showsCell shape, size, and tissue arrangementSpecific proteins the cells are producing
Main question it answersIs this cancer, and how does it look?What type of cancer, and what is it expressing?
How results are recordedGrade, margins, depth of invasionPositive or negative for each marker, with a score
When it is usedEvery biopsy as standardAdded when the routine exam needs more information
Typical reporting timePart of the initial reportOne to several extra working days

Still unclear?

Send your reports across and a specialist will walk you through what they mean — what is known, what is not, and what the options actually are.

Meet the Specialists

17+ senior cancer specialists. One panel for your case.

Trained at AIIMS, Tata Memorial, and leading international centres. Combined 150+ years of experience. Every complex case is reviewed by 3+ of them — together.

Dr. Naresh Gundu
Medical Oncologist

Dr. Naresh Gundu

MBBS, DNB (Internal Medicine), DM (Medical Oncology)

View Profile
Dr. C. Raghavendra Reddy
Medical Oncologist

Dr. C. Raghavendra Reddy

MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)

View Profile
Dr. Bharati Devi Gorantla
Medical Oncologist

Dr. Bharati Devi Gorantla

MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)

View Profile
Dr. Owais Mohammed
Medical Oncologist

Dr. Owais Mohammed

MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)

View Profile
Dr. T. Raghavender Reddy
Medical Oncologist

Dr. T. Raghavender Reddy

MBBS, DM (Medical Oncology), MD (Radiation Oncology)

View Profile
Dr. N. Kiranmayee
Medical Oncologist

Dr. N. Kiranmayee

MBBS, DM (Medical Oncology), MD (Internal Medicine)

View Profile
Dr. Muralidhar Muddusetty
Surgical Oncologist

Dr. Muralidhar Muddusetty

MBBS (AIIMS), MS (Surgery) (AIIMS), DNB (Surgical Oncology), MRCS (Edinburgh)

View Profile
Dr. Raghavendra Naik
Surgical Oncologist

Dr. Raghavendra Naik

MBBS, MS (General Surgery), M.Ch (Surgical Oncology)

View Profile
Dr. Mohammed  Imaduddin
Surgical Oncologist

Dr. Mohammed Imaduddin

M.B.B.S, MS (General Surgery), M.Ch (Surgical Oncology)

View Profile
Dr. Vinay Mamidala
Surgical Oncologist

Dr. Vinay Mamidala

MBBS, MS(General Surgery), M.Ch(Surgical Oncology), FMAS, FARIS(Ongoing)

View Profile
Dr. Paila Gowri Naidu
Surgical Oncologist

Dr. Paila Gowri Naidu

MBBS, MS (General Surgery), M.Ch (Surgical Oncology), FMAS

View Profile
Dr. Venkata Sushma P
Radiation Oncologist

Dr. Venkata Sushma P

MBBS, MD (Radiation Oncology)

View Profile
Dr. Kirti Ranjan Mohanty
Radiation Oncologist

Dr. Kirti Ranjan Mohanty

MBBS, MD (Radiation Oncology)

View Profile
Dr. Gangadhar Vajrala
Radiation Oncologist

Dr. Gangadhar Vajrala

MBBS, MD (Radiation Oncology), MPH

View Profile
Dr. Basudev Pokhrel
Hematologist

Dr. Basudev Pokhrel

MBBS, M.D (Immunohematology & Blood Transfusion)

View Profile
Dr. Mohammed Imran
Interventional Radiologist

Dr. Mohammed Imran

View Profile
Dr. Vajja Sandeep Kumar
Surgical Oncologist

Dr. Vajja Sandeep Kumar

MBBS, MS (General Surgery), DrNB (Surgical Oncology), FALS Oncology

View Profile
Dr. Sridhar Kamani
Surgical Oncologist

Dr. Sridhar Kamani

MBBS, MS (General Surgery), DrNB (Surgical Oncology)

View Profile

Want a specific doctor for your case? Mention them when booking.

Book Free Consultation

Get a straight answer from a specialist

45 minutes, your reports reviewed, your questions answered in plain language.

Book Free Consultation Call 1800 202 8726

Why did your pathologist add IHC to the report?

IHC is added when the basic microscope exam does not give enough information on its own. That is normal — it is not a sign of a problem with the sample or with your diagnosis.

The most common reasons are to confirm where the cancer started, to subtype it more precisely, or to check whether specific proteins are present that affect which treatment is most likely to work.

For some cancers, IHC marker testing is a routine part of every diagnosis. For breast cancer, for example, checking ER, PR, and HER2 is done as a matter of course — not because something is unclear, but because treatment decisions depend on those results.

Your oncologist can tell you exactly which markers were requested and what question each one was answering.

What does a positive or negative IHC result mean?

The same result can mean very different things depending on which marker and which cancer. A positive result for one marker may indicate that a targeted treatment is available. A positive for a different marker in a different cancer may point in another direction entirely.

This is why it is not possible to read an IHC result in isolation. The report is written for your oncologist, who reads each marker against your diagnosis, your stage, and your full clinical picture.

If your report has marker names you do not recognise, or results that are worrying you, write them down and bring the paper to your next appointment. Your oncologist will go through each one.

Did you know?

IHC is now a standard step in diagnosing most solid tumours, not a specialist add-on.

ASCO and ESMO guidelines list specific IHC markers as required before treatment decisions can be made for several of the most common cancer types.

Source: ASCO and ESMO clinical practice guidelines on pathological diagnosis

Explore 114 more Waiting For and Understanding Your Report topics

HUB — Cytology and Prostate Scoring Systems Explained

HUB — Understanding Your Biopsy Report

HUB — Waiting for Biopsy Results

All Waiting For and Understanding Your Report →

Next step

Still not sure what applies to you?

Send your reports across and a senior medical oncologist will go through what they mean, what is known, and what the options actually are.

Book Free Consultation Call 1800 202 8726
Common questions

Frequently asked questions

What does it mean if my IHC result is positive for a particular marker?

Positive means the protein was detected in your tumour tissue. What that means for you depends entirely on which marker it is and what cancer you have. A positive ER result in breast cancer has a specific treatment implication; a positive result for a different marker in a different cancer may mean something else entirely. Your oncologist is the right person to explain what each positive result means for your situation specifically.

Why does my pathology report have extra pages I do not understand?

IHC results are usually issued on separate pages or as an addendum, because they are processed after the main microscope examination and often arrive a few days later. The language is written for pathologists and oncologists. Each page typically lists the markers tested and the result for each. Bring the full report to your appointment so your oncologist can take you through the findings that are relevant to your treatment.

Does a positive IHC result mean the cancer is more serious?

Not necessarily. Whether a positive result is associated with a more or less serious outlook depends on which marker it is. Some markers, when positive, indicate that a targeted treatment is available and expected to help. Others provide information about how quickly cells are dividing, which your oncologist weighs alongside other findings. Positive does not automatically mean worse — your oncologist is the right person to put each result in context.

Can IHC tell where the cancer started?

Yes, and this is one of its main uses. When a cancer is found at a site that may not be its point of origin — a lymph node, the liver, or the lungs — a panel of IHC markers can give strong clues about the tissue it came from. This matters because treatment is generally chosen based on the original cancer type, not the site where it has spread. Your oncologist will explain what the panel found in your case.

How long does IHC take, and why is it slower than the rest of the report?

IHC typically adds one to several working days to the reporting time. After the initial microscope examination, the pathologist applies the antibodies, allows time for them to bind, and then processes and re-examines the tissue. If your report is marked preliminary, or if your oncologist is waiting on additional results before discussing treatment, this step is usually the reason. It is not a sign of a complication.

My IHC was done at a different laboratory. Is the result still reliable?

Yes. IHC is a standardised test and accredited laboratories use validated methods. It is common for the IHC portion of a report to be sent to a specialist referral laboratory, particularly for markers that require high-volume testing to maintain accuracy. If you have concerns about a specific result, your oncologist can request a review or a repeat test on the stored tissue sample.

Full index

Browse all 701 biopsy topics

Every page in this section, grouped by the part of the journey it belongs to. Pick a group to see what is in it.

What Is a Biopsy?

What Is a Biopsy? Everything You Need to Know →

Types of Biopsy Compared

Which Biopsy Will You Have? Techniques Compared →

Preparing for a Biopsy

What to Expect on the Day of Your Biopsy →

Recovery and Aftercare

After a Biopsy: Recovery, Aftercare and Warning Signs →

Biopsy by Body Part

Biopsy by Body Part: What to Expect at Each Site →

Understanding Your Report

How to Read a Biopsy Report: Terms Explained →

IHC and Molecular Markers

IHC and Molecular Markers on a Biopsy: What They Mean →

Grading and Scoring Systems

Cytology & Prostate Scoring Systems Explained →

How Accurate Is a Biopsy?

How Accurate Is a Biopsy? Errors and Second Opinions →

If Your Result Is Benign

Your Biopsy Is Benign: What It Means and What Comes Next →

Call now Book free consultation