Diagnosis

Gastric lymphoma

Etiology

Cause [pma]

• H pylori (the most common)

• Other infections: HIV, EBV, hepatitis B, and HTLV-1

Pathophysiology [pma]

A minority of patients with chronic H pylori-associated gastritis undergo this transformation

1. H pylori infection

2. --> Antigen stimulation

3. --> Recruits B-cells and T-cells to the gastric mucosa

4. --> Chronic inflammation

5. --> Malignant transformation into alow-grade gastric MALT lymphoma

6. --> Progress independently of the presence of H pylori

7. --> High-grade gastric lymphomas (DLBCL)

   • DLBCL has a worse prognosis than MALT lymphoma

   • Can arise from a transformation of MALT lymphoma or de novo

Classification [pma]

• Mucosa-associated lymphoid tissue (MALT) lymphoma (low-grade)

• Diffuse large B-cell lymphoma (DLBCL) (high-grade)

• Mantle cell lymphoma (rare)

• Follicular lymphoma (rare)

Epidemiology

Incidence per 100.000 [tdc][un9][qh4][pma]

Approach

• Blood test

• Gastroscopy

• Colonoscopy

• Endoscopic ultrasound

• Endoscopic biopsy with immunohistochemical testing

• Bone arrow aspiration

• CT

• MRI

• PET-CT

Staging

• Stage I: Confined to the gastrointestinal tract

• Stage II: Extending into the abdomen from the primary gastrointestinal site

  • Stage IIA: Local nodal involvement.

  • Stage IIB: Distant nodal involvement.

• Stage III: Lymphoma penetrates the serosa to involve adjacent organs or tissues

• Stage IV: Disseminated extranodal involvement or supradiaphragmatic nodal involvement

Treatment

1. Eradicate H pylori: two weeks of antibiotics and proton pump inhibitors [pma]

2. Early-stage low-grade gastric MALT lymphoma:

   • Endoscopic biopsy 3 to 6 months after H pylori eradication

   • Histologic remission may take 1 to 14 months post-H pylori eradication

   • If complete remission --> endoscopic biopsy every 6 months for the first 2 years

   • If incomplete eradication:

     • observation approach with gastric mapping biopsies every 3 to 6 months

     • localized radiation (remission rates >95%) or chemotherapy, with or without rituximab (screen for HIV, hepatitis B, and hepatitis C before starting rituximab)

     • 90% survival at 10 years

3. High-grade gastric MALT lymphoma:

   • H pylori treatment alone may lead to the remission in a minority of patients

   • Observation approach with gastric mapping biopsies every 3 to 6 months

   • Or an aggressive strategy according to patient preference:

     • Observation with endoscopy and abdominal imaging every 6 months

     • Radiation, chemotherapy, or immunotherapy with rituximab

   • 5-year survival: 70-99% (depending on histology, staging, comorbidities)

4. Surgery:

   • Acute bleeding not amenable to endoscopic therapy

   • Perforation

   • Obstruction

Differential diagnoses

Acute pancreatitis, Celiac disease, Cholelithiasis, Crohn disease, Diabetic gastroparesis, Diverticulitis, Gastric cancer, Gastritis, Gastroesophageal reflux disease, Menetriers disease, Pancreatic cancer, Ulcer disease