Splenic lymphoma with villous lymphocytes (SLVL) in Ghana

This thesis describes a B-cell lymphoma, splenic lymphoma with villous lymphocytes (SLVL), in Ghana. It is the first description of this disorder from tropical Africa where it may be more common than in temperate countries. In 10 patients, who could clearly be diagnosed as SLVL, the disorder is characterised by splenomegaly, lymphocytosis and typical villous lymphocytes with polar villi. In these patients evidence presented for the monoclonal nature of the lymphocytosis includes the presence of serum paraproteins, restricted immunoglobulin light chain expression and clonal rearrangement of immunoglobulin genes. The disorder differs from SLVL in Europe by affecting a younger age group and more women than men. It seems to be more aggressive than in Caucasians with a mortality rate of over 30% in 4 years. A second group of patients is identified by this study who have some of the features of SLVL, including splenomegaly and villous lymphocytosis, but in whom no monoclonal population of cells can be detected. Some of these patients also fulfill existing criteria for the diagnosis of hyper-reactive malarial splenomegaly (HMS). The frequency with which SLVL is associated with HMS suggests that HMS may be involved in the mechanism of lymphomagenesis. Malaria induces a polyclonal expansion of B-lymphocytes thereby providing a pool of cells with an increased potential for mutational chromosomal events. Full tumourgenesis may also require activation of oncogenes such as BCL-1