Fig. 11.

(a) In this case of hard palate plasmocytoma, a dense cellular infiltrate of monomorphic cells of plasmocytoid appearance is visible. Hematoxylin and eosin staining, primary objective magnification 10×. (b and c) By immunohistochemical studies, light chain production restriction was confirmed. In micrograph (b) positive cytoplasmic expression of kappa light chains in the tumor cells can be seen. In micrograph (c) no expression of lambda light chains is observed in the neoplasm. In both micrographs, primary objective magnification 40×.