Gastric cancer is the fourth most common cancer in the world and is the second leading cause of cancer-related deaths [
5]. Gastric cancer has become a major public health burden. In recent years, domestic and foreign literatures have reported that the age of onset of gastric cancer has become older [
6,
7], and its mortality rate has also increased with the increase in age [
8]. The clinical diagnosis and treatment of elderly patients with gastric cancer has become a very urgent and realistic problem. Studies on the diagnosis and treatment of gastric cancer in the elderly have been reported at home and abroad [
9,
10]. However, there are no studies on OCUS in the diagnosis of gastric cancer in elderly patients. Gastroscopy remains the main detection method and gold standard for gastric diseases. However, it brings about some pains and has contraindications. Due to age and physical factors, elderly patients cannot well tolerate the procedure and could not be easily examined. In the present study, among these symptomatic outpatient patients, patients who were ≥ 60 years old accounted for 39.48%, and the maximum age was 93 years old. From this, the requirement of suitable methods for gastric disease in elderly patients can be observed. OCUS was examined by filling the stomach with a food stomach contrast agent and forming a good ultrasonic interface with the stomach wall. OCUS can clearly display the five-layer structure of the gastric wall, lesions in gastric wall and their sizes, locations, and invaded layer of gastric wall. Clinicians can also observe the softness of the gastric wall through changes in the filling and emptying of the stomach. Its unique observation method is helpful for the further application of gastrointestinal ultrasound in clinic [
11‐
14]. At present, the diagnostic value of OCUS in many common gastric diseases has been recognized, especially for peptic ulcer, gastric cancer, lymphoma, gastric polypoid lesions, and submucosal lesions [
15‐
17]. When cutoff value of risk index based on OCUS parameters was set at 3 points, the sensitivity and specificity were 94.1% and 71.4%, respectively [
18]. It is an effective supplement for gastroscopy and provides an option for elderly patients who cannot undergo gastroscopy. In this study, 196 cases were examined by OCUS and gastroscopy during the same period [
18]. Cases of gastric cancer were diagnosed by OCUS, the detection rate was 9.18%, 19 cases were detected by gastroscopy, the detection rate was 9.69%, and the diagnostic accordance rate of ultrasound for gastric cancer was 94.73%. This is consistent with the results reported by Jun Lu and Chunmei Xu, in which the positive diagnostic rate of OCUS for gastric cancer was reported to be at 96.25% and 96%, respectively (Kappa = 0.972). This indicates that OCUS is an effective method for the detection of gastric cancer in elderly patients and can be used to substitute gastroscopy to detect gastric cancer in elderly patients, making up for the deficiency of gastroscopy in its application in elderly patients. Through observing changes in the thickness and the level structure and the function of local peristalsis of gastric wall, OCUS can provide many indices to indicate the presence of gastric cancer.