Splenic marginal zone B-cell lymphoma (MZBCL)

CD19+; CD5-; CD22+; CD23-; CD10-; CD25-/+; CD38+; CD11c-; CD103-; FMC7+; surface Ig bright+. The transformed cell represents an IgM+/IgD+ B-lymphocyte deriving from the marginal zone.

The translocation is rare (

These patients may feature a relatively aggressive clinical course as compared with other cases of splenic MZBCL

Usually, the abnormal lymphocytes in the PB smear are morphologically heterogeneous. The majority of cells are >14 mm in size, with pleomorphism of nuclear shapes, fine chromatin structure and distinct nucleoli. Some lymphocytes with short villi may be present along with larger lymphoid cells and rare prolymphocyte-like cells.

The bone biopsy may show B-lymphoid cells of intermediate size with an interstitial infiltration pattern. An intrasinusoidal pattern of growth was also noted.
The spleen specimens display a nodular lymphoid infiltrate of the white pulp by small lymphocytes mixed with larger blast cells with clear cytoplasm, centered on polyclonal follicle centers. Red pulp involvement may occur.

The patients may show partial responses to alkylating agent and to multiagenet chemotherapy.

Transformation into high-grade lymphoma was reported.

The tranlocation was described as a balanced t(11;14)(p11;q32).

To detect the 14q32 break, the cos-Ca1, cosIg6 and cos3/64 and YAC Y6 were used. Splitting of cosmid signals and Y6 signals has been detected, indicating a break downstream of the IgVH sequences, in the region flanked by cos3/64 and Y6. The gene involved at the 11p11 band is presently unknown.

del(7)(q22q32); +12; del(17)(p12). In one case a 7q- chromosome was the primary anomaly, the t(11;14) having found at the time of histologic transformation into high grade lymphoma