Rapid Discrimination Of Malignant Lesions From Normal Gastric Tissues Utilizing Raman Spectroscopy System: A Meta ?Analysis

ObjectiveGastric cancer is the fourth most common malignancy and the second leading cause of cancer deaths in humans worldwide. At present, white-light endoscopy is the most important conventional tool to diagnose gastric carcinoma, nonetheless, it heavily relies on the visual observation of gross morphological changes in pathologic tissues,leading to a poor diagnostic accuracy and bringing patients unexpected complications.In recent years, many studies have suggested that Raman spectroscopy system(RAS) might be a useful discriminative tool to identify the malignant lesions of the stomach. However, these studies were inconclusive because of mono-centric,inadequate sample sizes and different diagnostic algorithms employed. This meta-analysis is aimed to assess the diagnostic accuracy of RAS in the rapid diagnosis of gastric cancer with histopathology as the reference standard.MethodsWe searched a wide range of electronic databases for all published researches that assessed the diagnostic accuracy of RAS to detect gastric carcinoma. Full papers were obtained for potentially eligible studies and evaluated according to predefined criteria.The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. From each study, we extracted information on diagnostic performance of RAS. After exploring heterogeneity, we adopted a random effects model to pool related effect sizes.ResultsThe initial literature search identified 257 reference articles in which 15 relevant articles with 15 data sets were selected and reviewed. The pooled sensitivity and specificity of RAS in diagnosing gastric cancer were 0.89[95 %(confidence interval,CI) 0.84–0.92] and 0.92(95 % CI 0.88–0.95), respectively. The positive likelihood ratio,the negative likelihood ratio, and the area under the curve were 10(95 % CI 6.5–15.3),0.13(95 % CI 0.08–0.22), and 0.96(95 % CI 0.94–0.97), respectively. All the pooled estimates, calculated by random and fixed effect models, were similar. There was no evidence of considerable publication bias.ConclusionAccording to the data of this study, RAS is an objective and sensitive optical diagnostic technology for detecting gastric cancer and has advantages of being noninvasive to the body, real-time diagnosis, and ease of use. Consequently, it does deserve to be recommended. Moreover, this study might be an original meta-analysis of diagnostic trial which was utilized to investigate the performance of RAS on the early diagnosis of gastric cancer. Nonetheless, further investigations are also needed to focus on the precancerous lesions and(or) different subtypes of gastric cancer.