Canterbury DHB


MALT Lymphoma

Diagnosis, staging and management present unique problems in MALT lymphoma. 50% of these tumours have their origin in the GI tract, and of these 85% arise in the stomach. The other common sites are the lungs, head and neck, orbit, skin and thyroid.

Dissemination occurs in 35% of MALT without obviously altering their outcome, so extensive staging procedures may not be justified.

Distinguishing reactive from a malignant process can cause difficulty in the interpretation of MALT histology. Tumour cells express surface Ig and show light chain restriction. They are CD20+, 79a+, CD43 weak, CD21+ and 35+. They are negative for 5, 10 and 23 antigens. There is no specific phenotype. Cytogenetic abnormalities include trisomy 3 in 60%, and t(11;18) in 25 - 50%. The translocation t(11;18) is found in all cases of Helicobacter pylori (HP) negative and only 2% of HP positive gastric MALToma.

In This Section


Anti-tumour treatments


Helicobacter pylori is present in 90% of gastric MALToma. Both HP positive and negative gastric MALToma should receive triple therapy.

Other associations between MALT lymphoma and infection have been shown which should be treated appropriately; Chlamydia psittaci – doxycycline; Borellia burgdorferi (cutaneous MALT) – doxycycline; Campylobacter (immunoproliferative small intestinal disease) - erythromycin.

Anti-tumour treatments

About this Canterbury DHB document (5987):

Document Owner:

Peter Ganly (see Who's Who)

Last Reviewed:

December 2021

Next Review:

December 2024


Note: Only the electronic version is controlled. Once printed, this is no longer a controlled document. Disclaimer

Topic Code: 5987