Confocal laser endoscopy in the diagnosis for abdominal lymph node metastasis of gastric cancer

Confocal laser endoscopy (CLE) diagnostic criteria for lymph node metastasis of gastric cancer was established and evaluated to provide a basis for CLE clinical application in the diagnosis of abdominal lymph node metastasis. CLE scanning (surface scanning and sectional scanning) and pathology examination were conducted in gastric cancer tissues and lymph nodes of 5 cases. Characteristics of lymphatic metastasis in CLE imaging were observed and summarized in combination with pathology. The diagnostic criteria were corroborated in 124 lymph nodes of another 14 cases and CLE detection time needed for diagnosis was recorded. The CLE diagnostic criteria were tested and evaluated, and the effect of lymph node size on the diagnosis accuracy was determined. All the 19 participants were confirmed as gastric cancer. Sectional scanning can get comprehensive observation for internal structures of lymph nodes, in which abnormal large heterocyst appeared with special structural changes. CLE scanning could detect 88.75% of the positive metastasis and 68.18% of the negative metastasis examined by the pathology methods based on the established CLE diagnostic criteria. In comparison with pathological diagnosis, specificity, sensitivity and accuracy of CLE diagnosis were 88.75%, 68.18% and 81.45%, respectively. Accuracies of CLE diagnosis on the lymph nodes grouped by size were 85.29%, 77.78% and 88.89%, respectively, with no significant difference between groups (P > 0.05). Complete internal structures of lymph nodes can be observed clearly by CLE sectional scanning. The size of lymph nodes had no effects on diagnosis accuracy. CLE shows better sensitivity and specificity than traditional pathological diagnosis.