Published online Oct 7, 2017. doi: 10.3748/wjg.v23.i37.6894
Peer-review started: June 28, 2017
First decision: July 27, 2017
Revised: August 12, 2017
Accepted: September 6, 2017
Article in press: September 5, 2017
Published online: October 7, 2017
To examine usefulness of virtual biopsy using endocytoscopy by comparing the in vivo endocytoscopic and histopathological images of gastric cancers.
Endocytoscopy was performed in 30 patients with early gastric cancer. Of these, 26 patients showed well differentiated adenocarcinomas, while 4 patients showed poorly differentiated adenocarcinomas (including one signet ring cell carcinoma). Cancerous and non-cancerous areas were observed after double staining with 0.05% crystal violet and 0.1% methylene blue. The endocytoscopic images obtained were evaluated by an expert endoscopist and an expert pathologist without knowledge of patient clinical data, and endocytoscopic and histopathological diagnoses were compared.
The endocytoscopic images of the cancerous area were assessed as evaluable in 25 (83.3%) and 27 (90%) patients by endoscopist A and pathologist B, respectively, and those of the non-cancerous area as evaluable in 28 (93.3%) and 23 (76.7%) patients by the endoscopist and pathologist, respectively. The sensitivity, specificity, and diagnostic accuracy of gastric cancer diagnosis using evaluable endocytoscopic images were 88.0% and 92.9%, and 90.6% by endoscopist A, and 88.9% and 91.3%, and 90.0% by pathologist B, respectively. Evaluation of the diagnostic concordance rate between the endoscopist and the pathologist by inter-observer agreement calculation revealed no significant difference between the two observers. The inter-observer agreement (κ-value) for endocytoscopic diagnosis was 0.745.
Endocytoscopy is useful for the differentiation of cancerous from non-cancerous gastric mucosa, making it a promising tool for virtual biopsy.
Core tip: Endocytoscopy, which allows for ultra-high-magnifying observation of the gastrointestinal mucosa, has recently been developed, enabling the visualization of the gastrointestinal mucosa at resolutions approaching those of histology. Although the usefulness of virtual biopsy using endocytoscopy in the diagnosis of esophageal cancer, colorectal cancer, lung cancer and ulcerative colitis has been reported, few studies are available on the diagnosis of gastric cancer. This study showed the usefulness of virtual biopsy using endocytoscopy by comparing the in vivo endocytoscopic and histopathological images of gastric cancers.