Small bowel lymphoma
Updates to Article Attributes
Small bowel lymphoma is the most common small bowel malignancy, accounting accounts for ~25% of all primary small bowel malignancies and ~40% of all primary gastrointestinal lymphomas.
Epidemiology
Small bowel lymphoma is most commonly secondary extranodal involvement in widespread systemic lymphoma. When primary it is seen predominantly in well-defined patient groups, and the demographics, therefore, match those groups. Predisposing conditions include 1:
- HIV/AIDS
- coeliac disease
- organ transplant (see post-transplant lymphoproliferative disorder (PTLD)
- Helicobacter pylori positive patients
Clinical presentation
The presentation is variable and includes 1:
- gastrointestinal haemorrhage
- perforation
- small bowel obstruction (uncommon)
Pathology
The type of lymphoma depends on the underlying predisposing condition.
- H. pylori: mucosa-associated lymphoid tissue lymphoma (MALToma)
- PTLD: polyclonal B-cell non-Hodgkin's lymphoma (EBV-associated)
- HIV: B-cell non-Hodgkin's lymphoma 3, overall most common type
- T-cell lymphomas are seen but are uncommon 5; they have a greater tendency to perforate
Radiographic features
Typically, small-bowel lymphoma involves a single loop of bowel, with 5-20 cm of its length demonstrating 3:
- bowel wall thickening: 1-7 cm
- aneurysmal (or pseudoaneurysmal) dilatation (30%): occurs due to the replacement of muscularis by tumour or infiltration of myenteric nerve plexus 6
Despite the extensive involvement, small bowel obstruction is uncommon because of lack of desmoplastic reaction, and perforation is rare.
Regional lymph node enlargement in approximately 50% of cases.
Less frequently, the disease may manifest as a solid mass lesion (polypoidal/excentric). Differentiation from adenocarcinoma may be difficult. However, the presence of extensive retroperitoneal lymphadenopathy and splenomegaly favours lymphoma, whereas adjacent fat infiltration supports adenocarcinoma.
Treatment and prognosis
Most frequently, the involved segment is resected, with subsequent chemoradiotherapy 2.
Differential diagnosis
-
inflammatory bowel disease, especially Crohn
'sdisease - adenocarcinoma of the small bowel
- metastases:
- infection/enteritis
- leiomyoma/leiomyosarcoma/GIST
-<a href="/articles/inflammatory-bowel-disease-ibd">inflammatory bowel disease</a>, especially <a href="/articles/crohn-disease-1">Crohn's disease</a>- +<a href="/articles/inflammatory-bowel-disease-ibd">inflammatory bowel disease</a>, especially <a href="/articles/crohn-disease-1">Crohn disease</a>
-<li>metastases<ul>- +<li>metastases:<ul>
-<a href="/articles/renal-cell-carcinoma">renal cell carcinoma</a> <sup>3</sup>- +<a title="Renal cell carcinoma" href="/articles/renal-cell-carcinoma-1">renal cell carcinoma</a> <sup>3</sup>
-<li>breast carcinoma</li>-<li>lung carcinoma</li>- +<li><a title="Breast carcinoma" href="/articles/breast-neoplasms">breast cancer</a></li>
- +<li><a title="Lung cancer" href="/articles/lung-cancer-3">lung cancer</a></li>