Acid reflux symptoms can appear in the early stage of stomach cancer, but sleeping with acid reflux symptoms is not necessarily stomach cancer, as bad living habits, gastroesophageal reflux disease, etc. can lead to this symptom. Early stage of stomach cancer usually has no specific symptoms, and it can show symptoms similar to those of gastritis and peptic ulcer, such as acid reflux, heartburn, belching and so on. Sleeping with acid reflux is not unique to stomach cancer and cannot be taken as a sign of early stomach cancer. Under normal circumstances, the lower esophageal sphincter can prevent the reflux of gastric contents, but excessive eating before going to bed and eating indigestible food can lead to increased secretion of gastric acid, and at the same time, the change of sleeping position can lead to the increase of pressure at the esophageal cardia, and thus the reflux symptom occurs. If you suffer from gastroesophageal reflux disease (GERD), peptic ulcer, chronic gastritis, etc., the esophagus and stomach themselves are diseased, and the symptoms of acid reflux in sleep may also occur. Therefore, it is recommended to go to the hospital for diagnosis by a specialized doctor.