Of course, there are also circulating tumor DNA and methylated genes from blood, urine or feces that are still being evaluated. However, the sensitivity and specificity of a single tumor marker are suboptimal, and it is often necessary to combine several tumor markers for the screening and early diagnosis of tumors 2, 3, 4, 5. In clinical practice, markers commonly used to screen and diagnose tumors of the digestive system are mostly derived from blood, including carbohydrate antigen (CA50, 199, 242, 724), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), pepsinogen, etc.
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At present, tumor markers have been widely used for tumor screening and diagnosis, monitoring treatment response, and surveillance of tumor recurrence after treatment. Thus, early detection and timely treatment are integral for a favorable prognosis and long-term survival. have been associated high risk of morbidity and mortality based on the Global Cancer Statistics 2018 1. These tumors including colorectal cancer, stomach cancer, liver cancer, etc. The incidence of the digestive system neoplasm is rising yearly worldwide. Our analyses revealed that VOCs analysis could be considered as a potential novel tool to screen for malignant diseases of the digestive system. The diagnostic odds ratio and the area under the summary ROC curve for diagnosing neoplasm of the digestive system were 40.61 (95% CI 24.77–66.57) and 0.93 (95% CI 0.90–0.95), respectively. A total of 36 studies comprised of 1712 cases of neoplasm and 3215 controls were included in our meta-analysis. A bivariate mixed model was used and meta-regression and subgroup analysis were performed to identify possible sources of heterogeneity. The methodological quality of each study was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool.
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#REVMAN 5 META REGRESSION SOFTWARE#
STATA and Revman software were used for data analysis. An integrated literature search was performed by two independent investigators to identify all relevant studies investigating VOCs in diagnosing neoplasm of the digestive system from inception to 7th December 2020. This meta-analysis was aimed to estimate the diagnostic performance of volatile organic compounds (VOCs) as a potential novel tool to screen for the neoplasm of the digestive system.