Morphologic and immunophenotypic features of nodal MZL.

(A) Low-power view showing a parafollicular/perisinusoidal distribution of the neoplastic cells that surround some residual B-cell follicles (hematoxylin and eosin staining (H&E), × 100). (B) High-power view showing marginal zone/monocytoid B cells with medium-sized round (to irregular) nuclei and abundant pale cytoplasm (H&E, × 100). (C) CD20 staining showing strong positivity of the neoplastic cells (× 400). (D) Immunostaining for IgM, showing strong surface staining of the neoplastic lymphocytes (× 400).