Confocal endomicroscopy for in vivo detection of microvascular architecture in normal and malignant lesions of upper gastrointestinal tract

Background and Aim: Confocal laser endomicroscopy allows subsurface analysis of gastrointestinal mucosa during ongoing endoscopy. The present study assessed the feasibility of in vivo detecting superficial vascular architecture by confocal endomicroscopy in normal upper gastrointestinal mucosa and malignant lesions. Methods: Early gastric cancer in eight patients, superficial esophageal carcinoma in six patients, and asymptomatic normal control in 10 patients were studied by confocal endomicroscopy. The characteristic of endomicroscopic microvascular architecture from normal and malignant mucosa was described and images were evaluated. Results: Confocal endomicroscopy enabled clear visualization of the vascular networks of gastroesophageal mucosa. Honeycomb‐like and coil‐shaped regular microvascular architecture surrounding gastric pits were visible in the normal gastric body and antrum, respectively. Differentiated gastric cancerous mucosa showed hypervascularity and various caliber microvessels with irregular shapes. Undifferentiated gastric cancers disclosed a hypovascularity and irregular short branch vessels. Normal squamous epithelium had regular intraepithelial papillary capillary loops (IPCLs) directed toward the luminal surface. In superficial esophageal squamous carcinoma, dilated IPCLs were visible at the upper layer of the squamous mucosa. In esophageal adenocarcinoma, abnormal microvascular architecture showed tortuous and various calibers blood vessels. Of all the images, 41% were graded as good quality. The mean kappa value for interobserver agreement for the prediction of cancerous mucosa was 0.792. Conclusions: Confocal laser endomicroscopy system could yield very clear images of superficial microvascular network in the gastroesophageal mucosal layer both in malignant and normal mucosa. Endomicroscopic observation of vascular architecture may be of assistance in the identification of early gastroesophageal cancers.