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Updated: Aug 17, 2026

Evaluation of the Effectiveness of Longitudinal Incision for Endoscopic Submucosal Excavation of Gastric Subepithelial Lesions
Published on: April 28, 2026
Histopathological classification of nonneoplastic and neoplastic gastrointestinal submucosal lesions
1Institute of Pathology, Freiburg University Hospital, Freiburg im Breisgau, Germany.
Abstract:
This article provides an overview of the histopathologically defined nonneoplastic and neoplastic entities involved in submucosal lesions (SMLs) of the gastrointestinal tract, particularly those in the upper gastrointestinal tract. The gross appearance and the histomorphological and cytomorphological features of the most frequent SMLs are described, including gastrointestinal stromal tumor (GIST), leiomyoma, lipoma, carcinoid, granular-cell tumor, glomus tumor, schwannoma, submucosal metastases, Brunner's gland hamartoma, pancreatic rests, and cysts. The current state of important technical aspects of biopsy processing and the role of histology and cytology in the diagnosis of SMLs are discussed.
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