Lymphome splénique a lymphocytes villeux (SLVL)

Splenic lymphoma with villous lymphocytes (SLVL) is an indolent B-cell chronic lymphoproliferative disorder of the elderly characterised by splenomegaly without lymph nodes. Diagnosis is based on the presence of an absolute chronic lymphocytosis with circulating lymphocytes with an irregular cytoplasmic border. Cells express B-cell antigens, CD19, CD20, CD22, CD79b, FMC7 and are usually negative for CD5, CD23, CD10, CD43 and CD123. A nodular pattern of infiltration with a variable degree of paratrabecular deposits is frequently present in bone marrow biopsies. In patients with advanced disease, it is possible to see a diffuse pattern of infiltration. A pattern with intrasinusoidal infiltration could be also more specific. There is no genetic abnormality specific for SLVL but deletions of chromosome 7q are the commonest abnormality. Trisomy 3 and immunoglobulin gene translocations t(11;14)(q13;q32), t(11;14)(p11;q32) or t(9;14)(p13;q32 are observed in less than 10% of cases. Patients with p53 abnormalities (20% of cases), have significantly a shorter survival. SLVL cells may have either a mutated or unmutated immunoglobulin variable region genes but the patients with an unmutated profile could have a more aggressive disease. Hepatitis C Virus infection can be have a role in SLVL, as Helicobacter pylori in MALT gastric lymphomas, Campylobacter jejuni in immunoproliferative small intestinal disease, B. bugdoferi in cutaneous MALT or C. psittaci ocular MALT lymphomas.