Initial screening of gastric cancer using oral contrast-enhanced trans-abdominal ultrasonography in rural asymptomatic individuals

Background & aimsInitial screening for high-risk population of gastric cancer (GC) is needed in rural areas of large-population countries. This study aims to explore the feasibility of applying noninvasive ultrasonography as an initial screening strategy to improve the early diagnosis and prevention of GC.MethodsOral contrast-enhanced trans-abdominal ultrasonography (OCTU) was initially applied to screen around 15,000 residents from 24 different rural villages of Changxing Island in Shanghai, China, facilitating the identification of high-risk population for further endoscopy examination.Results176 subjects (1.18 %) were initially identified with gastric diseases using OCTU while 14,787 ones (98.93 %) were normal with negative results. 145 out of 176 individuals (82.39 %) took further endoscopy examination, and 16 were diagnosed with GC with biopsy examination, with 9 of them at the early stage. We followed up with the Center for Disease Control and Prevention, and identified another 6 GC cases occurred within one year among OCTU-negative population, serving as an adjustment factor for sensitivity analysis. As a result, with a total of 22 GC cases included in this cohort, the positive predictive rate, the negative predictive value, sensitivity, and specificity were 9.09％, 99.96 %, 75.5 %, and 98.93 %, respectively.ConclusionsOCTU is feasible, non-invasive, low-cost, and widely acceptable in rural area, thus we proposed that OCTU is practicable to serve as a supplementary screening method to improve the early detection of GC in rural area of China and other developing countries with large population.