Immunohistochemistry — how your lymphoma subtype is identified

What Is Immunohistochemistry in Lymphoma?

Immunohistochemistry — usually shortened to IHC — is a laboratory test performed on the tissue from your biopsy. It uses antibodies that latch onto specific proteins, called markers, on and inside the lymphoma cells. Wherever a marker is present, a colour develops that the pathologist can see under the microscope. In effect, IHC lets the lab "paint" the cells according to which proteins they carry.

This matters because most lymphomas look broadly similar on a plain stain. What separates one subtype from another is the pattern of markers they express. IHC is the step that turns a general finding — "this is a lymphoma" — into a precise subtype diagnosis. And the subtype decides almost everything that follows: whether the disease is slow-growing or aggressive, whether it is watched or treated promptly, and which class of therapy is likely to work.

IHC is run after your lymph node biopsy and is reported as part of your lymphoma pathology report. For the full picture of diagnosis and care, see our Lymphoma hub and Lymphoma Treatment in Hyderabad page.

Why an Accurate IHC Diagnosis Matters at CION

Getting the subtype right is the foundation of effective lymphoma care. CION builds every treatment plan on a complete, tissue-based diagnosis — never a rushed one.

How Immunohistochemistry Is Performed

IHC is a careful, multi-step process, which is part of why a full lymphoma diagnosis takes days rather than hours. In outline:

• Fixing and sectioning — the biopsy tissue is preserved and cut into ultra-thin slices mounted on glass slides
• Applying antibodies — each slide is treated with an antibody that binds one specific marker; a colour reaction reveals where that marker is present
• Interpretation — a pathologist reads the pattern across the whole panel, judging which cells are positive, how strongly, and where they sit
• Second-round markers — the first results often prompt further stains to narrow the subtype, so the panel is chosen step by step

Because it works on the solid tissue, IHC keeps the tumour's architecture intact — a strength that a fluid-based test cannot match. It is frequently paired with flow cytometry, and, when needed, with molecular and genetic testing.

Key IHC Markers in Lymphoma — What They Mean

No single marker gives the diagnosis — the pathologist reads the whole pattern. This table shows some of the most common markers and what a positive result typically points to.

This is a general guide, not a diagnosis. The exact panel and its interpretation vary by case and are decided by a pathologist. Marker naming follows the WHO classification, as referenced in NCCN and ESMO lymphoma guidelines.

CD20 and CD30 — the markers you may hear most about

Among the CD20, CD30 lymphoma markers, these two come up often because they do double duty: they help diagnose the subtype and they point to therapy.

CD20 — the B-cell marker

CD20 sits on the surface of most B cells. When a lymphoma is CD20-positive, it confirms a B-cell origin and tells the team that an anti-CD20 monoclonal antibody — a class of immunotherapy delivered directly at CION — may form part of treatment. Because so many common lymphomas are CD20-positive, this single marker often shapes the therapeutic approach.

CD30 — the Hodgkin and large-cell marker

CD30 is strongly positive in classic Hodgkin lymphoma and in some aggressive T-cell and large-cell lymphomas. As with CD20, its value is twofold: it supports the diagnosis and identifies an antibody-based treatment target in selected cases. Your oncologist will explain whether your CD30 status opens up such an option.

Note: markers describe what class of therapy may help. Specific drug names and regimens are always individualised and are discussed on our Lymphoma Treatment in Hyderabad page, not decided from a marker alone.

Where IHC Fits in Your Lymphoma Work-Up

IHC is one important piece of a bigger picture. A full lymphoma diagnosis and plan usually draws on several tests, each answering a different question:

• The biopsy — an excisional (whole-node) biopsy is preferred over an FNA because IHC needs enough tissue with intact architecture; a core needle biopsy is an alternative when surgery isn't feasible
• Flow cytometry — adds fast, quantitative immunophenotyping that complements IHC
• Molecular & genetic testing — cell-of-origin and double-hit testing when the IHC pattern raises the question
• Blood tests — routine bloods and LDH gauge disease burden and general health
• A bone marrow biopsy — a bone marrow exam checks whether lymphoma has reached the marrow
• Staging imaging — the Deauville score reads your PET scan and helps track response

All of these come together in your pathology report and are reviewed as one. If an enlarged node was found on a scan or a report mentions bulky disease, the same principle applies — the tissue diagnosis leads.

When to Get a Second Opinion on Your IHC

Because the subtype drives the entire plan, a second opinion on the pathology is especially worthwhile in a few situations:

• If key markers were not tested — a limited panel may miss the distinction between two subtypes that are treated very differently
• If the report is uncertain or borderline — a neuropathology-style re-review of the slides can confirm the subtype before treatment begins
• Before starting therapy — particularly where the choice hinges on a marker such as CD20 or CD30, or on molecular results still pending

CION offers a dedicated, free written second-opinion service with transparent costs explained up front — a plan built around healing, not billing. Request your free second opinion or call 18002028726.

Not Sure Your Lymphoma Subtype Is Confirmed?

Get a free written second opinion from CION's lymphoma tumour board — especially valuable if your IHC panel was limited or the report is unclear.