Splenic lymphoma, also termed as lymphomatous involvement of the spleen, represents the most common malignancy to involve the spleen. They are commonly secondary, rarely being primary (referred as primary splenic lymphoma).
This article focuses on the location-specific primary and secondary lymphomas involving the spleen, for a broader and systemic discussion, please refer to the main article on lymphoma.
The spleen is involved in about 30% of all Hodgkin lymphoma and 30-40% of patients with systemic non-Hodgkin lymphoma 2,4. The primary splenic lymphoma is rarer, representing about 2% of all lymphomas 2.
Lymphoma can often present with B symptoms (fever, night sweats and weight loss 3), please refer to the main article for further discussion in the systematic presentation.
Both primary and secondary splenic lymphoma may cause left upper quadrant pain 3.
Splenomegaly is perhaps the most common manifestation on imaging, but a normal size spleen does not exclude lymphoma involvement 2,3. Associated enlarges splenic hilum lymph nodes may be seen either in the primary or secondary forms. The secondary form will show signs of disease involving other organs and systems, particularly nodal disease.
The focal disease may manifest as small circumscribed nodules or bulky splenic masses 2 and, generally, these are hypoechogenic on ultrasound. A diffuse infiltrative disease is usually only characterized as an enlarged spleen 3.
Single or multifocal disease will present as well-defined masses 1-2:
- T1: low to iso-intensity compared to the background parenchyma
- T2: low to iso-intensity compared to the background parenchyma
- T1 C+ (Gd): focal lesions will have a mild or absent enhancement compared to the background parenchyma 2,3
- DWI: relatively low ADC values inferring diffusion restriction 3