Diagnostic Challenges Caused by Endoscopic Biopsy of Colonic Polyps: A Systematic Evaluation of Epithelial Misplacement With Review of Problematic Polyps From the Bowel Cancer Screening Program, United Kingdom.

摘要: Endoscopic mucosal biopsy may misplace elements into the submucosa of colonic adenomas, mimicking invasive adenocarcinoma. Biopsy-related misplacement can be more challenging to recognize than typical misplaced epithelium (pseudoinvasion) in pedunculated polyps. We compared features 16 polyps with biopsy-related those 10 adenomas pseudoinvasion and adenocarcinoma performed Ki67 p53 immunostaining on all cases. Features referred Bowel Cancer Screening Program Expert Board United Kingdom were also evaluated for same morphologic features. epithelial occurred throughout colon often appeared infiltrative (69%), including cells singly dispersed within reactive fibroinflammatory stroma or granulation tissue (44%). Misplaced displayed only low-grade cytologic was associated extruded mucin (75%), tattoo pigment (63%), normal glands (38%); scant lamina propria muscularis mucosae present (88% 44%, respectively). Cases contained infiltrative-appearing (91%) that cytologically low grade (72%), nondysplastic (11%), showed other signs injury. In contrast, always had a lobular contour rim propria, hemorrhage, and/or hemosiderin. Invasive carcinomas malignant cytology desmoplasia; most (70%) lacked trauma. staining patchy weak epithelium, whereas increased one both markers. Pathologists should aware endoscopically manipulated contain simulates malignancy.