Clinical Research
Copyright ©2007 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Feb 7, 2007; 13(5): 768-773
Published online Feb 7, 2007. doi: 10.3748/wjg.v13.i5.768
Esophageal mesenchymal tumors: Endoscopy, pathology and immunohistochemistry
Xuan Zhu, Xiao-Qian Zhang, Bi-Min Li, Ping Xu, Kun-He Zhang, Jiang Chen
Xuan Zhu, Xiao-Qian Zhang, Bi-Min Li, Ping Xu, Department of Gastroenterology, First Affiliated Hospital, Nanchang University, Nanchang 330006, Jiangxi Province, China
Kun-He Zhang, Jiang Chen, Department of Digestive Diseases, First Affiliated Hospital, Nanchang University, Nanchang 330006, Jiangxi Province, China
Author contributions: All authors contributed equally to the work.
Supported by the Scientific and Technological Foundation of the Jiangxi Provincial Department of Science and Technology
Correspondence to: Dr. Xuan Zhu, Department of Gastro-enterology, the First Affiliated Hospital, Nanchang University, Nanchang 330006, Jiangxi Province, China. jyyfyzx@163.com
Telephone: +86-791-8692505 Fax: +86-791-8623153
Received: October 9, 2006
Revised: December 1, 2006
Accepted: December 26, 2006
Published online: February 7, 2007
Abstract

AIM: To study the endoscopic, pathological and immuno-histochemical features of esophageal mesenchymal tumors.

METHODS: Twenty-nine patients diagnosed as esophageal mysenchymal tumors by electronic endoscopy and endoscopic ultrasound (EUS) were observed under light microscopes, and all tissues were stained by the immunohistochemical method. The expression of CD117, CD34, SMA and desmin were measured by staining intensity of cells and positive cell ratios.

RESULTS: Endoscopically, esophageal gastrointestinal stromal tumors (GISTs) and leiomyomas (LMs) had similar appearances, showing submucosal protuberant lesions. They all showed low echo images originated from the muscularis propria or muscularis mucosa on EUS. Endoscopy and EUS could not exactly differentiate esophageal GISTs from LMs. Microscopically, there were two kinds of cells: spindle cell type and epitheloid cell type in esophageal GISTs. Leiomyomas and leiomyosarcomas were only of spindle cell type. One malignancy was found in five cases of esophageal GISTs, and one malignancy in 24 cases of leiomyomas and leiomyosarcomas. Using Fisher’s exact method, the differences of malignant lesion proportion were not significant between esophageal LMs and GISTs, 1/5 vs 1/24 (P > 0.05). All cases of esophageal GISTs were positive for CD117, and 3 cases were also positive for CD34. The 24 cases of leiomyomas and leiomyosarcomas were all negative for CD117 and CD34. The differences of positive rates of CD117 and CD34 were significant between esophageal GISTs and LMs, 5/5 vs 0/24, 3/5 vs 0/24 (P < 0.005). All leiomyomas and leiomyosarcomas were positive for SMA, and desmin. Among 5 cases of esophageal GISTs, 2 cases were SMA positive, and 1 case was desmin positive. The differences in positive rates and expression intensity of SMA and desmin were significant between esophageal LMs and GISTs, 24/24 vs 2/5, 24/24 vs 1/5 (P < 0.005).

CONCLUSION: The most common esophageal mesenchymal tumors are leiomyomas, and esophageal GISTs are less common. Most of esophageal LMs and GISTs are benign. Endoscopy and EUS are the effective methods to diagnose esophageal mesenchymal tumors and they can provide useful information for the treatment of these tumors. However, they cannot exactly differentiate esophageal GISTs from LMs. Pathological, especially immunohistochemical features are useful to differentiate GISTs from leiomyomas.

Keywords: Esophageal mesenchymal tumors; Gastro-intestinal stromal tumors; Leiomyomas; Endoscopy; Pathology; Immunohistochemistry