case_images: PMC8414616_01
case_images: Colonoscopy finding of a polypoid 4-cm cecal mass (white arrow) underneath a clot.
  Endoscopic features of AL amyloidosis include thickening of the valvulae conniventes,
  mucosal ulcerations, multiple polypoid protrusions, and tumor-like lesions.
case_images: 10.1177_2050313X211040018-fig1.jpg
case_images: PMC8414616_01_10.1177_2050313X211040018-fig1.jpg
case_images: fig1-2050313X211040018
case_images: Colonoscopy revealed a polypoid cecal mass with an adjacent ulcer (Figure 1).
case_images: Histology of the cecal mass. (a) Hematoxylin-eosin-stained section showing thrombosed
  blood vessels demonstrating abundant homogeneous pink deposits in its walls (blue
  arrow). (b) Congo red stain positive material demonstrated in the walls of a vascular
  malformation (green arrow). (c) Abundance of lambda light-chain deposits in the
  pericecal lymph node. (d) Apple green birefringence under polarized light showing
  amyloid aggregates in the submucosa (SM) below the muscular mucosa (M). (e) Apple green
  birefringence reflected under polarized light within the arterial walls. (f) Apple green
  birefringence reflected under polarized light within the walls of the malformations.
case_images: 10.1177_2050313X211040018-fig2.jpg
case_images: PMC8414616_01_10.1177_2050313X211040018-fig2.jpg
case_images: fig2-2050313X211040018
case_images: There was no evidence of lymphoma noted on the surgical specimen; however, primary light chain amyloidosis was confirmed by immunochemistry with lambda chain predominance (Figure 2).