Symptomatic Primary (AL) Amyloidosis of the Stomach and Duodenum
Figure 2
Biopsies from the gastric corpus stained with Congo red, with extracellular deposits between the gastric glands (a) and apple-green birefringence seen under polarized light (b). Immunohistochemical examination of a bone marrow biopsy showed a normal density of immunoglobulin kappa () chain (c) and an increased density of immunoglobulin lambda () chain positive cells (d).