Figure 1

Lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) diffusely involving BM. (a) Representative field of the neoplasm showing small lymphoma cells. Note the Dutcher bodies in the field (hematoxylin-eosin). (b) Double staining for BCL-10 and CD20 demonstrates nuclear and cytoplasmic BCL-10 expression restricted to the neoplastic cells that are highlighted by the CD20 membranous stain. (a, b. Original magnification for all images is × 200).