Post-Gastric Endoscopic Mucosal Resection Surveillance Biopsies: Evaluation of Mucosal Changes and Recognition of Potential Mimics of Residual Adenocarcinoma

Abstract

Endoscopic mucosal resection (EMR) offers curative treatment for patients with node-negative early gastric carcinoma of less than 2 cm without ulceration or ulceration scar. Follow-up biopsies are frequently performed to ensure the absence of residual neoplasia. We performed a retrospective analysis of post-EMR biopsies from 33 patients who underwent gastric EMR. Histologic changes included inflammation (100%), stromal edema (97.0%), foveolar hyperplasia (78.8%), ectatic vessels (66.7%), epithelial atypia (60.6%), increased glandular mitoses (57.6%), epithelial anisonucleosis (54.5%), fibrinopurulent materials (51.5%), ischemia (48.5%), stromal hemorrhage (33.3%), mucin depletion (12.1%), clear cell degeneration (15.2%), and signet-ring cell-like change (6.1%). Especially, clear cell degeneration and signet-ring cell-like change were conspicuous in the area of ischemia. Residual adenocarcinomas were noted in 4 of 33 cases, and consistently showed high nuclear-to-cytoplasmic ratio with high glandular density. Glandular clear cell degeneration and/or signet-ring cell-like change were worrisome and sometimes difficult to be distinguished from residual neoplastic glands. However, these degenerative glands were usually embedded in a nondesmoplastic stroma and showed anisonucleosis of glandular epithelia. Mimics of residual adenocarcinoma, namely clear cell degeneration and signet-ring cell-like change should be judiciously assessed to avoid unnecessary surgery.

Gastric pseudo-signet ring cells: a potential diagnostic pitfall

“…Benign epithelial signet ring cells in the stomach have also been reported previously in association with ischaemia and ulceration [3][4][5]. We report two cases of benign signet ring cell change in gastric biopsy specimens which we believe to be a degenerative non-neoplastic change.…”

British Society of Gastroenterology guidelines on the diagnosis and management of Barrett's oesophagus

“…This should not be confused with true ulceration. Biopsy samples taken 1–16 days after gastric ER can show signet ring cell change and clear cell degeneration in areas of ischaemia 246. Although there are no relevant studies that looked at mucosal changes after ER, tissue regeneration in the immediate post-ER period can hamper proper histological assessment, and therefore it is recommended to delay post-ER biopsies to 6–8 weeks (Evidence grade IV).…”

Nuclear artifacts in gastric endoscopic submucosal dissection specimens: A clinicopathological study

“…ESD-related nuclear changes may infrequently mimick dysplasia due to concomitant nuclear enlargement, overlapping, or hyperchromatism and structural abnormality, which have been mentioned in gastric post-EMR biopsy sites (5) and electrical device-related extragastrointestinal specimens (10,13,14). Moreover, in our experience, ESD-related artifacts may be misdiagnosed as adenocarcinoma.…”

“…Since the early 1980s, endoscopic resection (ER) techniques using electrothermal devices, such as polypectomy, strip biopsy and endoscopic mucosal resection (EMR), have been developed as diagnostic and curative procedures for gastrointestinal mucosal lesions (1)(2)(3)(4)(5)(6). The latest modality using specialized electrosurgical knives, referred to as endoscopic submucosal dissection (ESD), has enabled more complete removal of gastric lesions and is currently accepted as a standard treatment of early gastric adenocarcinoma (EGA) (6)(7)(8).…”