Splenic marginal zone lymphoma (SMZL) is an indolent low-grade B-cell lymphoma composed of small to intermediate-sized lymphocytes that proliferate within the spleen and splenic hilar lymph nodes. Bone marrow and peripheral blood are usually involved, but lymphadenopathy and extranodal disease are uncommon.

SMZL is a very rare lymphoid neoplasm that occurs primarily in adults older than 50 years (median age is 67-68 years) with no sex predominance.

Patients present with splenomegaly and/or peripheral blood lymphocytes that appear villous. Thrombocytopenia and/or anemia may also be present. Patients are often asymptomatic at time of diagnosis, and initial abnormalities are identified incidentally on blood work.

An association between SMZL and chronic hepatitis C virus (HCV) has been identified in several case series, and in some cases, antiviral therapy for chronic HCV has resulted in regression of SMZL.

Related topics: Nodal marginal zone lymphoma; Extranodal marginal zone lymphoma