Guidelines Summary
Gastric MALT Lymphoma
National Comprehensive Cancer Network (NCCN) guidelines recommend the following studies to establish a diagnosis of gastric MALT lymphoma [18] :
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Endoscopic biopsy; fine needle aspiration (FNA) is never acceptable
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Immunohistochemistry panel: CD20, CD3, CD5, CD10, BCL2, kappa/lamda, CD21 or CD23, cyclin D1, BCL6
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Cell surface marker analysis by flow cytometry: kappa/lambda, CD19, CD20, CD5, CD23, CD10
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Helicobacter pylori stain; if positive, then polymerase chain reaction (PCR) or fluorescence in situ hybridization (FISH) for t(11;18)
The following studies may be useful in select circumstances:
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Molecular analysis for detection of antigen receptor gene rearrangements or if plasmacytic differentiation is present, MYD88 mutation status
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FISH or cytogenetics for detection of t(1;14), t(3;14), t(11;14), t(11;18)
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FISH or PCR: t(14;18)
The European Society for Medical Oncology (ESMO) recommends serology, urea breath test, and/or stool antigen test for H pylori in cases where immunohistochemistry findings are negative. [38]
The NCCN guidelines recommend antibiotic therapy for stages I and II in H pylori–positive patients, followed by endoscopy/biopsy for restaging at 3 months or sooner if symptomatic. Further treatments include second-line antibiotics, if H pylori testing remains positive, and involved-site radiation therapy (ISRT) if lymphoma positive. Patients who are t(11;18) positive can be treated with rituximab if ISRT is contraindicated. For patients who are H pylori negative, ISRT is the preferred treatment. Rituximab is the alternative if ISRT is contraindicated. [18]
Patients with advanced stage disease should be observed unless they have one of the following indications for treatment [18] :
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Candidate for a clinical trial
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Symptoms
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GI bleeding
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Threatened end-organ function
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Bulky disease
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Steady or rapid progression
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Patient preference
For first-line therapy, the NCCN prefers the following regimens [18] :
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Bendamustine + rituximab
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RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone)
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RCVP (rituximab, cyclophosphamide, vincristine, prednisone)
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Rituximab
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Ibritumomab tiuxetan (category 2B)
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Lenalidomide + rituximab (category 2B)
The ESMO guidelines are in general agreement with NCCN for the treatment of gastic MALT lymphoma. [38]
Nongastric MALT Lymphoma
The NCCN guidelines recommend the following studies to establish a diagnosis of nongastric MALT lymphoma [18] :
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Immunohistochemistry panel: CD20, CD3, CD5, CD10, BCL2, kappa/lamda, CD21 or CD23, cyclin D1
-
Cell surface marker analysis by flow cytometry: kappa/lambda, CD19, CD20, CD5, CD23, CD10
The following studies may be useful in select circumstances:
-
Molecular analysis for detection of antigen receptor gene rearrangements or if plasmacytic differentiation is present, MYD88 mutation status
-
FISH or cytogenetics for detection of t(3;14), t(11;14), t(11;18)
-
FISH or PCR: t(14;18)
For stage I and II, the preferred treatment is ISRT. Surgery may be considered for certain sites (ie, thyroid, colon/small bowel and lumpectomy for breast). Rituximab and observation are options in select cases. [18]
For advanced stages, the treatment options are ISRT, observation in select cases or first-line therapy regimens as listed above for gastric MALT lymphoma. [18]
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Low magnification micrograph of a lymphoepithelial lesion of the gastrointestinal tract in the setting of a primary gastrointestinal tract lymphoma. H&E stain. Colonic biopsy (descending colon). Lymphoepithelial lesions are strongly associated with mucosa-associated lymphoid tissue lymphomas (MALT lymphomas); however, they may appear in other types of lymphomas.
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High magnification micrograph of a lymphoepithelial lesion of the gastrointestinal tract in the setting of a primary gastrointestinal tract lymphoma. H&E stain. Colonic biopsy (descending colon). Lymphoepithelial lesions are strongly associated with mucosa-associated lymphoid tissue lymphomas (MALT lymphomas); however, they may appear in other types of lymphomas.
