{"entity":{"id":"lymphoma-tx-h-pylori-eradication","kind":"term","name":"Helicobacter pylori eradication as cancer treatment in gastric MALT lymphoma","aka":["Antibiotic treatment of gastric lymphoma","Triple therapy for MALT lymphoma","Quadruple therapy"],"tldr":"Gastric MALT lymphoma is grown by a stomach bacterium, and killing the bacterium with a ten to fourteen day course of antibiotics cures most cases. It is the only common cancer whose first-line treatment is an antibiotic.","summary":"The observation was published in 1993: in six patients with low-grade gastric MALT lymphoma, eradicating Helicobacter pylori made the lymphoma regress in five. The mechanism is that the lymphoma depends on antigen-driven stimulation by the organism, so removing the stimulus removes the driver, at least until the clone acquires a translocation that frees it.\n\nWhat is given. A standard eradication regimen chosen by local antibiotic resistance: a proton pump inhibitor with clarithromycin and amoxicillin or metronidazole for 10 to 14 days, or a bismuth-containing quadruple regimen where clarithromycin resistance is high. The regimen is the same one used for peptic ulcer disease; there is no oncological version of it.\n\nWhat has to be checked afterwards. Eradication must be confirmed, by urea breath test or stool antigen at least four weeks after the antibiotics and two weeks after stopping the proton pump inhibitor, because incomplete eradication is the commonest reason for the lymphoma not to respond and it is easily missed. Endoscopy with biopsies is repeated every three to six months. Regression is slow: histological disappearance can take twelve to eighteen months, and persistent minimal histological disease in an asymptomatic patient with successful eradication is watched rather than treated.\n\nWhat predicts failure. The t(11;18)(q21;q21) translocation, which produces an API2-MALT1 fusion, makes the lymphoma independent of the bacterium and predicts failure of eradication; testing for it identifies patients who will need radiotherapy or systemic treatment sooner. Deep invasion beyond the submucosa, nodal involvement and a Helicobacter-negative tumour also predict failure, although eradication therapy is still given to many Helicobacter-negative cases because a proportion respond.\n\nRelated infections at other MALT sites are treated on the same reasoning with far weaker evidence: doxycycline for Chlamydia psittaci in ocular adnexal MALT, antibiotics for Borrelia burgdorferi in cutaneous MALT, and for Campylobacter jejuni in immunoproliferative small intestinal disease.","asOf":"2026-09-29","links":[{"label":"Wotherspoon et al., regression of gastric MALT lymphoma after Helicobacter pylori eradication, Lancet 1993","url":"https://doi.org/10.1016/0140-6736(93)91409-F"},{"label":"Zucca et al., marginal zone lymphomas: ESMO clinical practice guidelines, Annals of Oncology 2020","url":"https://doi.org/10.1016/j.annonc.2019.10.010"},{"label":"NCI PDQ: adult non-Hodgkin lymphoma treatment (health professional)","url":"https://www.cancer.gov/types/lymphoma/hp/adult-nhl-treatment-pdq"}],"tags":[],"related":[],"cancers":["malt-lymphoma","marginal-zone-lymphoma","gastric"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["endoscopy","lymphoma-tx-radiotherapy","lymphoma-tx-watch-and-wait"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-wotherspoon-h-pylori-malt-lancet-1993","paper-esmo-marginal-zone-lymphoma-zucca-ann-oncol-2020"],"journals":[],"dependsOn":[],"notes":[],"category":"Clinical"},"route":"/terms/lymphoma-tx-h-pylori-eradication/","neighbours":{"cancer":[{"id":"malt-lymphoma","kind":"cancer","name":"Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma)","route":"/cancers/malt-lymphoma/"},{"id":"gastric","kind":"cancer","name":"Gastric & gastro-oesophageal junction cancer","route":"/cancers/gastric/"},{"id":"marginal-zone-lymphoma","kind":"cancer","name":"Marginal zone lymphoma","route":"/cancers/marginal-zone-lymphoma/"}],"term":[{"id":"endoscopy","kind":"term","name":"Endoscopy (EGD, EUS, ERCP)","route":"/terms/endoscopy/"},{"id":"lymphoma-tx-radiotherapy","kind":"term","name":"Radiotherapy in lymphoma: involved-site fields, 24 Gy, 4 Gy and total skin electron therapy","route":"/terms/lymphoma-tx-radiotherapy/"},{"id":"lymphoma-tx-watch-and-wait","kind":"term","name":"Watch and wait in lymphoma: when the right treatment is none yet","route":"/terms/lymphoma-tx-watch-and-wait/"}],"paper":[{"id":"paper-esmo-marginal-zone-lymphoma-zucca-ann-oncol-2020","kind":"paper","name":"Marginal zone lymphomas: ESMO clinical practice guidelines","route":"/key-papers/paper-esmo-marginal-zone-lymphoma-zucca-ann-oncol-2020/"},{"id":"paper-wotherspoon-h-pylori-malt-lancet-1993","kind":"paper","name":"Regression of primary low-grade gastric MALT lymphoma after eradication of Helicobacter pylori","route":"/key-papers/paper-wotherspoon-h-pylori-malt-lancet-1993/"}]}}