Duodenal localization of plasmablastic myeloma

Figure 1 Histological examination of duodenal mucosa biopsy samples. A: Low-power histological examination of duodenal mucosa fragments shows a hypercellular inter-glandular stroma (hematoxylin-eosin, original magnification × 4); B, C: At medium- and high-power; B: Hematoxylin-eosin, original magnification × 10; C: Hematoxylin-eosin, original magnification × 40), an infiltration of the lamina propria by atypical cells is better appreciated, with neoplastic cells displaying medium to large size pleomorphic nuclei, sometimes with prominent nucleoli, and scanty cytoplasm; D-F: CD138 immunostaining shows a strong and diffuse membrane staining, revealing the plasma cell nature of the neoplastic infiltrate (D: Original magnification × 4; E: Original magnification × 40), with prevalent λ chain immunohistochemical expression (F: Original magnification × 40).