B-prolymphocytic leukaemia--a mantle zone lymphoma?

A case of prolymphocytic lymphoma/leukaemia (PL) sensu Galton in a 32-year-old man is presented. The leucocyte count was 19.0 x 10(9)/1 at presentation and tartrate resistent acid phosphatase was present in most prolymphocytes. Immunological investigation of prolymphocytes from lymph nodes, spleen and peripheral blood revealed the surface marker phenotype: SmIg + (mu, (delta), lambda), IgG-Fc-receptor +, C3-receptor +. The prolymphocytes from lymph nodes and spleen were C3-receptor + in a high percentage, while only a few were IgG-Fc-receptor +. This proportion was reversed in the blood prolymphocytes. The histology of lymph nodes was unique and strongly suggested a preferential involvement (homing phenomenon) of the mantle zone of the lymphatic follicle. These results may indicate that emission of prolymphocytes from lymph nodes to circulation involves a change of surface receptors. It is finally suggested to consider the diagnosis of not only hairy-cell leukaemia but also PL in the case of tartrate resistent acid phosphatase-positive lymphoma/leukaemia.