A comparative study of the diagnostic value of endoscopic ultrasonography with pathological features of upper gastrointestinal mesenchymal tumors.

OBJECTIVE: To study the pathological and immunohistochemical features of upper gastrointestinal mesenchymal tumors (GIMTs) and compare them with endoscopic ultrasonographic (EUS) characteristics so as to evaluate the diagnostic value of EUS in upper digestive tract GIMTs. METHODS: Seventy-two pathological specimens of upper digestive tract GIMTs (34 surgical specimens and 38 endoscopic mucosal resection (EMR) specimens) were collected. The pathological features and the expression of CD(117), CD(34), SMA and S-100 were observed by immunohistochemical method with light microscope. The pathological types and characteristics were determined by pathologists and compared with the layer of origin and sonographic characteristics determined with preoperative EUS. RESULTS: In the 72 cases of upper digestive tract GIMTs, 37 cases were diagnosed as stromal tumor with pathological and immunohistochemical methods (51.4%); 21 of them were malignant, accounting for 56.7% of the stromal tumors. Thirty-four cases were diagnosed as leiomyoma (47.2%) and 1 case as schwannoma (1.4%). In the 72 GIMTs cases, 40 were esophageal GIMTs. EUS showed that 38 cases were originated from the muscularis mucosae layer; 33 of them were leiomyoma and 5 stromal tumor. The 2 cases originating from the muscularis propria layer which were both stromal tumors. Thirty-two cases were gastric GIMTs, EUS showed that 2 cases originating from the muscularis mucosae layer were gastric stromal tumor. Of the 30 cases originating from the muscularis propria layer, 28 cases were stromal tumor, 1 case was leiomyoma and 1 case was schwannoma. The sensitivity and the specificity of EUS in distinguishing benign and malignant stromal tumors according to sonographic characteristics were 81.0% and 93.8% respectively. CONCLUSION: Stromal tumor is more common in stomach mesenchymal neoplasms and is more often originated from the muscularis propria layer in EUS; leiomyoma is more common in esophagus and is more often originated from the muscularis mucosae layer. The diagnostic sensitivity and specificity of EUS are high in distinguishing benign and malignant character of upper digestive tract GIMTs. EUS plays an important role in guiding the clinical management of upper digestive tract GIMTs.