Submucosal hematoma is a highly suggestive finding for amyloid light-chain amyloidosis: Two case reports

Figure 1 Initial colonoscopy revealed reddish elevated lesions within plaque-like erythema in the sigmoid and transverse colon. A: Initial colonoscopy showing a submucosal hematoma in the transverse colon; B: Repeat colonoscopy showing a discoid discoloration where the submucosal hematoma was located; C: Biopsy from submucosal hematoma showing mucosal hemorrhages and deposition of amorphous material in the lamina propria (hematoxylin-eosin stain); D: Biopsy from discoid lesion showing deposition of amorphous material in the lamina propria and in the vessel walls of the submucosa (hematoxylin-eosin stain); E: Congo red stain showing amyloid deposition; F: Apple-green birefringence under polarized light.

Figure 2 Endoscopic biopsies were performed for the submucosal hematomas. A: Colonoscopy showing submucosal hematomas from the ascending colon to the rectum; B and C: Biopsy showing mucosal hemorrhages and deposition of amorphous material in the lamina propria and in the vessel walls of the submucosa (hematoxylin-eosin stain and direct fast scarlet stain); D: Staining with κ was positive.