Figure 7.

Subcutaneous tissue suspension cytospin and flow cytometry. Tissue suspension cytospin preparation (A) shows many atypical lymphoid cells of medium size with irregular nuclear contours and less clumped nuclear chromatin. Few large Reed-Sternberg like cells and mononuclear cells are seen (black arrows). Flow cytometry analysis on 2 soft-tissue lesions (B) (LT elbow and RT shoulder), both showing a large monotypic B cell population expressing CD19, CD5, CD20, and CD79b with Lambda light chain restriction. There is partial expression of CD23 and FMC7, with no significant expression of CD200.