Small bowel lymphoma

Epidemiology

• Comprise about 20% of primary small bowel malignancies
• One third of GIT lymphomas occur in the small bowel
• In children <10yo, this is the most common intestinal neoplasm

Risk factors

• Coeliac disease
• Immunodeficiency (e.g. AIDS)

Pathophysiology

• Primary small bowel lymphoma arises from lymphoid follicles of intestinal submucosa - therefore seen most commonly in areas with lots of lymphoid tissue (ileum and sometimes jejunum)
• Mostly NHL
  • Large B cell lymphoma is most common
  • Follicular subtype has good prognosis
• Burkitt's lymphoma - near ileocaecal junction - very aggressive
• Malignant lymphomas can involve the small bowel as a manifestation of systemic disease too
• Gross appearance - typically large, >5cm, and may extend beneath the mucosa

Presentation

• Abdo pain, anorexia, weight loss, diarrhoea, palpable mass
• Fever is uncommon and suggests systemic involvement
• Nearly always bulky lymphadenopathy

Workup:

• CT Neck/CAP, PET, endoscopic evaluation of whole GIT, LDH, beta-2-microglobulin, bone marrow biopsy

Management:

• Limited evidence because it's so rare. Commonly resection (if low overall disease burden) with adjuvant CTX (likely CHOP or R-CHOP)
• B-cell lymphomas are more chemo-sensitive than T-cell lymphomas
• Asymptomatic - no surgery, often chemo-responsive
• Any symptoms - resection indicated - progression to haemorrhage or perforation portends a dismal prognosis
• T-cell lymphomas are more likely to need resection

Complications

• More common in T-cell lymphomas
• Obstruction
• Perforation (up to 25% of all patients)

Prognosis

• 5 year survival 50-60%, dictated by response to systemic therapy rather than success of surgical resection
• 5-year survival seems significantly higher in patients who got CTX than those who did not