[A comparative study of CT virtual endoscopy imaging and pathologies of lower alimentary tract mesenchymal tumors]

To study the pathological and immunohistochemical features of alimentary tract mesenchymal tumors and compare with computed tomographic virtue endoscopy (CTVE) imaging technology to evaluate the diagnostic value of CTVE in alimentary tract mesenchymal tumors.

Seventy-four pathological specimens of alimentary tract mesenchymal tumors 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 CTVE imaging technology.

In the 74 cases of alimentary tract mesenchymal tumors, 40 cases were diagnosed as stromal tumor with pathological and immunohistochemical methods(54.1%). Sixteen of them were malignant, accounting for 40% of the stromal tumor while 33 cases were diagnosed as leiomyoma (44.6%) and 1 case as schwannoma (1.4%). In the 74 GIMTs cases, 33 were jejunum GIMTs, 21 were ileum GIMTs and 20 were large intestine GIMTs. Immunohistochemistry assay in the 74 GIMTs cases showed that 51.4% GIMTs were positive for CD(117), approximately 36.5% were positive for CD(34), 62.2% were positive for smooth-muscle actin (SMA) and 1.4% were positive for S-100 protein. In the 74 GIMTs cases, 69 cases were diagnosed right in the accuracy for location with CTVE (93.2%) with 51 cases in small intestinal (94.4%) and 18 cases in large intestinal (90.0%). The sensitivity and the specificity of CTVE to distinguish benign from malignant stromal tumors by CTVE characteristics were 84.2% and 85.7% respectively.

GIST is common in GIMTs and is often originated from the small intestinal. The immunohistochemistry has great value in diagnosing alimentary tract mesenchymal tumors. The CTVE imaging technology also has great value in diagnosing alimentary tract mesenchymal tumors which can show the localization, shape size and artery of the tumor clearly. The diagnostic sensitivity and specificity of CTVE are high to distinguish benign from malignant alimentary tract GISTs. CTVE plays an important role in guiding the clinical management of GISTs.