Pathology and Staging: Decoding Your Lab Results
At a Glance
MALT lymphoma pathology reports use specific markers like CD20 to confirm the diagnosis. The t(11;18) translocation is a critical test indicating the lymphoma may not respond to antibiotics alone. Doctors use the Lugano system for staging and the MALT-IPI score to predict disease behavior.
Understanding your pathology report and staging is like learning the “genetic signature” and “road map” of your lymphoma. This information tells your care team exactly what type of cells they are dealing with and how far they have traveled, which directly influences your treatment plan [1].
Reading Your Pathology Report
The pathology report is the definitive document that confirms you have MALT lymphoma. It uses immunohistochemistry (IHC)—a process where scientists use special “stains” to identify proteins on the surface of your cells [2].
The Completeness Checklist
MALT lymphoma belongs to a group of “small B-cell lymphomas.” To distinguish it from other similar cancers (like CLL or Mantle Cell lymphoma), pathologists look for a specific pattern of markers [2][3].
| Marker | Typical Result for MALT | Why It Matters |
|---|---|---|
| CD20 | Positive (+) | Confirms it is a B-cell lymphoma [2]. |
| CD79a | Positive (+) | Another “signature” of a B-cell [2]. |
| CD5 | Negative (-) | Helps rule out CLL and Mantle Cell lymphoma [2]. |
| CD10 | Negative (-) | Helps rule out Follicular lymphoma [3]. |
| Cyclin D1 | Negative (-) | Rules out Mantle Cell lymphoma [3]. |
The t(11;18) Translocation: A Critical Test
A translocation occurs when pieces of two different chromosomes swap places. In gastric MALT lymphoma, one of the most important genetic markers is t(11;18) [4].
This test is crucial because the presence of t(11;18) is a strong predictor that the lymphoma is “autonomous.” This means it no longer needs the H. pylori bacteria to survive and is highly unlikely to disappear with antibiotics alone [4]. If you have this translocation, your doctor may suggest moving more quickly to radiation or other therapies [5].
Staging: Lugano vs. Ann Arbor
“Staging” describes how much lymphoma is in the body. While the Ann Arbor system is famous for other lymphomas, doctors often prefer the Lugano Classification for MALT lymphoma, especially when it is in the stomach or intestines [6][7].
- Stage I (Lugano): The lymphoma is limited to the organ where it started (e.g., just the stomach wall) [8]. Under Lugano, multiple gastrointestinal lesions can still be summarized as Stage I.
- Stage II: The lymphoma has spread to nearby lymph nodes.
- Stage III: The lymphoma has spread to lymph nodes on both sides of the diaphragm. (Note: True Stage III is rare for primary gastric MALT lymphoma but is a standard part of the staging criteria).
- Stage IV: The lymphoma is “disseminated,” meaning it is found in multiple distant organs [1].
Risk Stratification: The MALT-IPI
To help predict how the disease will behave, doctors use the MALT International Prognostic Index (MALT-IPI). This is a simple scoring system based on three risk factors [1][9]:
- Age: Being 70 years or older.
- Stage: Having Stage III or IV disease.
- LDH Level: Having an elevated level of lactate dehydrogenase (a protein found in the blood when cells are damaged).
Your Score:
- 0 factors: Low Risk (Excellent outlook) [1].
- 1 factor: Intermediate Risk [1].
- 2 or more factors: High Risk [1].
Other biomarkers, such as Beta-2 microglobulin (B2-M) and Ki-67 (which measures how fast cells are dividing), may also be used to give a more complete picture of your specific risk profile [10].
Common questions in this guide
What does a CD20 positive result mean for MALT lymphoma?
Why is the t(11;18) translocation test important?
What is the Lugano Classification?
What is a MALT-IPI score?
Questions to Ask Your Doctor
Curated prompts to bring to your next appointment.
- 1.Does my pathology report show that the cells are CD5-negative and CD10-negative?
- 2.Was my tissue tested for the t(11;18) translocation, and if so, what was the result?
- 3.According to the Lugano system, what stage is my lymphoma?
- 4.What was my LDH level at the time of diagnosis, and how does it affect my risk score?
- 5.Given my staging and risk markers, is H. pylori eradication alone enough to start with, or should we consider other options like radiation?
Questions For You
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References
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PMID: 40793830 - 10
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PMID: 40297783
This page is for informational purposes only and does not replace professional medical advice. Always consult your oncologist or pathologist for help interpreting your specific MALT lymphoma lab results.
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