title: 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.
authors.affiliation: Department of Pathology, Saitama Medical School, Saitama, Japan. mitsut@mail.tains.tohoku.ac.jp
authors.forename: Tomoko
authors.initials: T
authors.lastname: Mitsuhashi
authors.forename: Gregory Y
authors.initials: GY
authors.lastname: Lauwers
authors.forename: Shinichi
authors.initials: S
authors.lastname: Ban
authors.forename: Mari
authors.initials: M
authors.lastname: Mino-Kenudson
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Ogawa
authors.forename: Shinichi
authors.initials: S
authors.lastname: Ota
authors.forename: Michio
authors.initials: M
authors.lastname: Shimizu
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D003937:Diagnosis, Differential; D016145:Endoscopy, Digestive System / Q000009:adverse effects; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000175:diagnosis*; D012189:Retrospective Studies; D013272:Stomach Diseases / Q000209:etiology / Q000473:pathology; D013274:Stomach Neoplasms / Q000473:pathology / Q000601:surgery*