What is the treatment approach for gastric lymphoma?

Treatment Approach for Gastric Lymphoma

Treatment Strategy Based on Lymphoma Type

For gastric MALT lymphoma, H. pylori eradication with antibiotics is the first-line treatment for localized disease, while high-grade gastric lymphomas (diffuse large B-cell lymphoma) should be treated with primary chemotherapy, avoiding surgery as initial management. 1, 2

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MALT Lymphoma (Low-Grade) Treatment Algorithm

Initial Management for H. pylori-Positive Disease

• Start with H. pylori eradication therapy using PPI-based triple therapy (PPI + clarithromycin + either amoxicillin or metronidazole) for 10-14 days as sole initial treatment for localized gastric MALT lymphoma 1
• Confirm eradication with urea breath test or stool antigen test at least 6 weeks after therapy and at least 2 weeks after PPI withdrawal 1
• If initial eradication fails, attempt second-line therapy with alternative triple- or quadruple-therapy antibiotic regimens 1
• Wait at least 12 months before considering alternative treatment in patients who achieve clinical and endoscopic remission with H. pylori eradication, even if histological lymphoma persists 1

Management for H. pylori-Negative or Antibiotic-Refractory Disease

• For H. pylori-negative patients, consider a trial of antibiotics (occasional responses occur), but if no regression is seen at repeat endoscopy 2-3 months after antibiotics, proceed to oncological treatment 1
• For localized disease (stage I-II), moderate-dose involved-field radiotherapy is the preferred option: 24-30 Gy to the stomach and perigastric nodes over 3-4 weeks 1
• Patients with t(11;18) translocation are unlikely to respond to antibiotics and may be unresponsive to alkylating agents alone 1

Systemic Disease Management

• For stage IV or symptomatic systemic disease, use systemic chemotherapy with oral alkylating agents (cyclophosphamide or chlorambucil) or purine nucleoside analogs (fludarabine, cladribine) 1
• Rituximab plus chemotherapy (particularly rituximab plus chlorambucil) is the most appropriate choice for disseminated disease requiring treatment 1
• Chemoimmunotherapy should be preferred in cases of histological transformation or contraindications to radiotherapy 1

Follow-Up Protocol

• Perform endoscopy with multiple biopsies 2-3 months after treatment to document H. pylori eradication 1, 3
• Continue endoscopic surveillance at least twice yearly for 2 years to monitor histological regression 1, 3
• For persistent but stable residual disease, a wait-and-see policy is safe with continued surveillance 1, 3
• Long-term follow-up includes annual blood counts and appropriate imaging 1, 3

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High-Grade Gastric Lymphoma (Diffuse Large B-Cell) Treatment Algorithm

Primary Treatment Approach

• Chemotherapy is the treatment of choice for high-grade gastric lymphoma in early stages (IE and II1), not surgery 2
• The controlled trial by Aviles et al. demonstrated that chemotherapy alone achieved 92% event-free survival at 10 years compared to 28% with surgery alone 2
• Surgery is associated with significant morbidity and mortality without survival benefit and should be avoided as initial treatment 2, 4

Chemotherapy Regimens

• Use CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) at standard doses as the primary chemotherapy regimen 2, 4
• ProMACE/MOPP is an alternative adriamycin-containing regimen 4
• Primary chemotherapy achieves 75% complete response rates with endoscopic confirmation 4

Role of Radiotherapy

• Add involved-field radiotherapy (40 Gy) after chemotherapy for patients with limited disease (stage I-II) 2, 4
• Radiotherapy consolidation improves local control in early-stage disease 4

Surgery Indications (Limited)

• Surgery should only be performed for urgent complications (perforation, uncontrolled bleeding) or in patients who fail to respond to primary chemotherapy 1, 2
• When surgery is necessary, it should be followed by chemotherapy, with radiotherapy added for stage II2 disease 5
• Surgery combined with chemotherapy (SCT) achieved 82% event-free survival at 10 years, but chemotherapy alone was superior (92%) with less toxicity 2

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Critical Pitfalls to Avoid

• Do not perform upfront gastrectomy for high-grade gastric lymphoma—chemotherapy is superior and surgery increases treatment-related mortality 2
• Do not abandon antibiotic therapy prematurely in MALT lymphoma—lymphoma regression can take up to 12 months after H. pylori eradication 1
• Do not treat persistent monoclonal B-cells after histological regression as treatment failure—watchful waiting is appropriate 1
• Be aware that 12% of patients may develop acute gastrointestinal bleeding shortly after starting chemotherapy for high-grade lymphoma, though perforation is rare 4
• Surgery for MALT lymphoma impairs quality of life without superior results compared to conservative approaches 1

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Staging Requirements

• Perform gastroduodenal endoscopy with multiple biopsies from all gastric regions, duodenum, and gastroesophageal junction 1
• Endoscopic ultrasound is essential to evaluate regional lymph nodes and depth of gastric wall infiltration 1
• Complete staging includes CBC, LDH, β2-microglobulin, CT chest/abdomen/pelvis, and bone marrow biopsy 1
• FISH or PCR for t(11;18) translocation helps identify patients unlikely to respond to antibiotics 1