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PubMed This is a summary of 15 peer-reviewed journal articles Updated
Oncology

Symptoms and Diagnosis: Finding the Answers

At a Glance

MALT lymphoma is a slow-growing cancer with symptoms that vary depending on its location, such as the stomach, lungs, or eyes. Diagnosis requires a tissue biopsy, H. pylori testing for gastric cases, and imaging like a CT scan to determine the extent of the disease.

Because MALT lymphoma is so slow-growing, it can be a bit of a “chameleon”—its symptoms are often vague and depend entirely on where in the body the lymphoma is located [1]. In many cases, it is found “incidentally” during a test for something else, such as a routine endoscopy or a chest X-ray [1][2].

Symptoms: Listen to the Location

The symptoms you experience will mirror the organ where the B-cells have gathered.

  • Gastric (Stomach) MALT: This is the most common form. Patients often report epigastric pain (pain in the upper middle stomach), a persistent feeling of indigestion, nausea, or feeling full after eating only a small amount [3][4]. Occasionally, it can cause bleeding, which may appear as dark stools or vomiting blood [3].
  • Pulmonary (Lung) MALT: Many patients have no symptoms at all. If they do, they might experience a mild cough or slight shortness of breath [1][2].
  • Salivary Gland MALT: This often shows up as a painless, slow-growing swelling in the cheek or jaw area (the parotid glands) [5].
  • Ocular (Eye) MALT: Patients may notice a “salmon-pink” patch on the white of the eye, swelling of the eyelid, or a feeling of pressure behind the eye [6].

The Diagnostic Path

Confirming a diagnosis of MALT lymphoma requires a “puzzle-piece” approach, combining physical exams, imaging, and lab work.

1. Tissue Biopsy: The Gold Standard

The only way to definitively diagnose MALT lymphoma is through a biopsy. A doctor must take a small sample of the suspicious tissue and look at it under a microscope [7]. Specialists called pathologists use immunohistochemistry—a process of staining the cells—to look for specific B-cell markers that confirm it is a marginal zone lymphoma [8].

2. Testing for H. Pylori

Since most gastric cases are caused by the H. pylori bacteria, testing for its presence is mandatory.

  • 13C-Urea Breath Test (UBT): You drink a specialized liquid and then breathe into a bag. If the bacteria are present, they break down the liquid and release a specific gas that can be measured [9]. It is highly accurate.
  • Stool Antigen Test: This checks for bacterial proteins in a stool sample.
  • Important Note on Medications: Taking certain medications before these tests can cause a “false negative.” You must stop acid-blockers (PPIs) for at least 2 weeks and antibiotics or bismuth for at least 4 weeks prior to testing. Always talk to your doctor about how to safely pause your stomach medications so you don’t accidentally get an incorrect diagnosis.

3. Staging and Imaging

Once the cancer is confirmed, your team needs to see if it has spread.

  • Endoscopy: For gastric MALT, a doctor uses a flexible camera to look at the stomach lining and take multiple samples [10][11].
  • CT Scan: Standard contrast-enhanced CT scans are often the preferred imaging method. While PET/CT scans (which use radioactive sugar) are common in other cancers, MALT lymphoma frequently has “low FDG avidity” (it does not absorb the sugar well), meaning it might not show up clearly on a PET scan [12]. Don’t be alarmed if your doctor prefers a standard CT.
  • Bone Marrow Biopsy: While common in other lymphomas, this is often omitted for early-stage gastric MALT because the cancer is so likely to be localized that the test rarely changes the treatment plan [13][14].

Standard Diagnostic Checklist

According to major guidelines (like NCCN or ESMO), a complete workup should include:

  1. Complete physical exam and medical history.
  2. Blood work (CBC, LDH levels, and metabolic panel) [15].
  3. Confirmation of H. pylori status (for stomach cases) [10].
  4. Imaging (usually a CT scan).
  5. Site-specific tests (like an eye exam for ocular cases).

Return to Home Page

Common questions in this guide

What are the most common symptoms of MALT lymphoma?
Symptoms depend entirely on where the lymphoma is located. Gastric MALT often causes upper stomach pain, indigestion, or feeling full quickly. If the lymphoma is in the lungs, salivary glands, or eyes, it may cause a mild cough, painless swelling, or sometimes no symptoms at all.
Can my acid reflux medication interfere with MALT lymphoma testing?
Yes. Taking acid-blocking medications like proton pump inhibitors (PPIs) can cause a false negative on an H. pylori breath or stool test, which is a crucial part of diagnosing gastric MALT lymphoma. You typically need to stop taking PPIs for at least two weeks before testing.
How is MALT lymphoma definitively diagnosed?
A tissue biopsy is the gold standard for diagnosis. A doctor takes a small sample of suspicious tissue and examines it under a microscope using special stains to look for specific B-cell markers that confirm the disease.
Will I need a PET scan to stage my MALT lymphoma?
Standard CT scans are often preferred over PET scans for staging MALT lymphoma. This type of cancer frequently has low sugar uptake, meaning it does not absorb the radioactive sugar used in PET scans well and might not show up clearly.
Is a bone marrow biopsy always necessary for staging?
For early-stage gastric MALT lymphoma, a bone marrow biopsy is often omitted. Because the cancer is so highly localized to the stomach in these early stages, a bone marrow test rarely changes the recommended treatment plan.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.What was the specific result of my H. pylori test, and which method (biopsy, breath, or stool) was used?
  2. 2.I've been taking a proton pump inhibitor (PPI) for my stomach; could that have caused a 'false negative' on my H. pylori test?
  3. 3.Based on my imaging results, do you think a bone marrow biopsy is absolutely necessary for my staging?
  4. 4.If my lymphoma is in a non-gastric site like my lungs or eyes, what specific imaging is best for monitoring my response to treatment?
  5. 5.What molecular markers, such as Ki-67 or BCL2, were found in my biopsy, and what do they tell us about how 'active' the cells are?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (15)
  1. 1

    Retrospective Analysis of 9 Cases of Primary Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma and Literature Review.

    Du C, Zhang J, Wei Y, et al.

    Medical science monitor basic research 2018; (24()):233-240 doi:10.12659/MSMBR.912762.

    PMID: 30581188
  2. 2

    Primary Mucosa-Associated Lymphoid Tissue Lymphoma of the Lung: A Case Report.

    Kim MY, Kim HJ, Kim JH

    Journal of the Korean Society of Radiology 2026; (87(1)):134-140 doi:10.3348/jksr.2025.0020.

    PMID: 41669737
  3. 3

    Five-year Progress of Gastric MALT Lymphoma Presenting as Gastric Outlet Obstruction.

    Gu H, Cheung DY, Seo YJ, et al.

    The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi 2023; (81(6)):265-269 doi:10.4166/kjg.2023.026.

    PMID: 37350522
  4. 4

    Uncommon presentation of gastric mucosa-associated lymphoid tissue lymphoma in a 13-year-old girl: acute vomiting of blood as the initial symptom.

    Jin X, Jin X, Guo P, et al.

    Annals of medicine and surgery (2012) 2024; (86(5)):3001-3004 doi:10.1097/MS9.0000000000001705.

    PMID: 38694317
  5. 5

    Tongue Atrophy in Sjögren Syndrome Patients with Mucosa-associated Lymphoid Tissue Lymphoma: Autoimmune Epithelitis beyond the Epithelial Cells of Salivary Glands?

    Zampeli E, Kalogirou EM, Piperi E, et al.

    The Journal of rheumatology 2018; (45(11)):1565-1571 doi:10.3899/jrheum.180101.

    PMID: 30008454
  6. 6

    Atypical Optic Neuritis as a Manifestation of Ocular Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma: A Case Report.

    Sequeira Quesada C, Vega Monge MA

    Cureus 2025; (17(6)):e85856 doi:10.7759/cureus.85856.

    PMID: 40656336
  7. 7

    Isolated superior oblique muscle extranodal marginal zone B cell lymphoma: case report.

    Alhammad F, Maktabi A, Alkatan HM, et al.

    Saudi journal of ophthalmology : official journal of the Saudi Ophthalmological Society 2018; (32(1)):66-68 doi:10.1016/j.sjopt.2018.02.003.

    PMID: 29755275
  8. 8

    Gastric Mucosa-associated Lymphoid Tissue Lymphoma Mimicking Signet Ring Cell Carcinoma.

    Choi HI, Lee BE, Kim KB, et al.

    The Korean journal of helicobacter and upper gastrointestinal research 2023; (23(2)):132-136 doi:10.7704/kjhugr.2023.0018.

    PMID: 40502284
  9. 9

    SMOKING IMPACTS HELICOBACTER PYLORI ERADICATION: RESULTS FROM A BRAZILIAN UNIVERSITY HOSPITAL.

    Fonte AACFRD, Cunha-Silva M, Rondon MVSDS, et al.

    Arquivos de gastroenterologia 2025; (62()):e25059 doi:10.1590/S0004-2803.24612025-059.

    PMID: 41172432
  10. 10

    [Characteristics of Gastric Mucosa-associated Lymphoid Tissue Lymphoma in Korea].

    Kim TW, Kim JS

    The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi 2024; (84(6)):243-250 doi:10.4166/kjg.2024.108.

    PMID: 39716946
  11. 11

    Helicobacter pylori Reinfection Diagnosed by Endoscopic and Histologic Recurrence in a Patient with Gastric Mucosa-Associated Lymphoid Tissue Lymphoma.

    Sugiyama T, Nanjyo S, Nakajima T, Kato C

    Case reports in gastroenterology 2023; (17(1)):41-48 doi:10.1159/000528309.

    PMID: 36742100
  12. 12

    Role in staging and prognostic value of pretherapeutic F-18 FDG PET/CT in patients with gastric MALT lymphoma without high-grade transformation.

    Park YJ, Hyun SH, Moon SH, et al.

    Scientific reports 2021; (11(1)):9243 doi:10.1038/s41598-021-88815-2.

    PMID: 33927319
  13. 13

    Prevalence and Implications of Bone Marrow Involvement in Patients with Gastric Mucosa-Associated Lymphoid Tissue Lymphoma.

    Choi SI, Kook MC, Hwang S, et al.

    Gut and liver 2018; (12(3)):278-287 doi:10.5009/gnl17217.

    PMID: 29409307
  14. 14

    A comparison of clinical staging using the Lugano versus Ann Arbor classifications in Japanese patients with Hodgkin lymphoma.

    Makita S, Maruyama D, Maeshima AM, et al.

    Asia-Pacific journal of clinical oncology 2020; (16(3)):108-114 doi:10.1111/ajco.13248.

    PMID: 31802636
  15. 15

    Marginal B-cell lymphoma: A 10-year retrospective study at national institute of hematology and blood transfusion, Vietnam.

    Vu BD, Nguyen HQ, Le CQ, et al.

    SAGE open medicine 2025; (13()):20503121251334508 doi:10.1177/20503121251334508.

    PMID: 40297783

This page provides information on MALT lymphoma symptoms and diagnosis for educational purposes. Always consult your oncologist or healthcare provider for personalized diagnostic evaluation and medical advice.

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