Search

We studied pathogenic gene mutations and tumor mutation burden (TMB) in visible low-grade dysplastic lesions in patients with inflammatory bowel disease (IBD). The dysplastic lesions with histologically normal mucosa in the background (group 1) were compared with dysplastic lesions occurring either in a background of chronic active colitis (group 2) or associated with synchronous carcinomas regardless of the status of the background mucosa (group 3). The TMB in group 3 was consistently higher in comparison to the group 1 and group 2 lesions, although the difference was not statistically significant. There also seem to be different mutation profiles between the groups, indicating different pathways of tumor pathogenesis. More frequent APC mutations were seen in group 1 as compared to other groups and TP53 mutations were seen in groups 2 and 3, but none in group 1. Molecular characterization could potentially be used as an ancillary prognostic marker in challenging cases to guide the further management of IBD patients with visible dysplastic lesions., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Yttrium-90 microsphere radioembolization ((90)Y MRE) is a therapy for liver malignancies by permanently implanting (90)Y-containing microspheres into tumors via hepatic artery. The etiology of persistent gastric ulcerations in patients presenting months after treatment remains unclear. Three patients who presented with gastric ulceration 4 to 13 months after (90)Y MRE were examined by esophagogastroduodenoscopy and biopsies. Pathological examinations showed multiple (90)Y microspheres scattered within the lamina propria and submucosa. Most of the microspheres were distributed in a linear fashion, consistent with an intravascular location; however, the vascular lumen and endothelial cells were not present. The microspheres were surrounded by fibrotic tissue infiltrated by chronic inflammatory cells and rare neutrophils. Epithelial granulation without pititis and miniaturized glands with intervening fibrosis were noted, compatible with chronic ischemic changes. These findings suggest that the persistent gastric ulceration is a result of localized ischemic injury in response to (90)Y MRE-induced vascular damage., (Copyright © 2015 Elsevier Inc. All rights reserved.)