Diagnosis typically begins with a detailed medical history and physical examination. The primary diagnostic tool for gastric cancer is an upper endoscopy (esophagogastroduodenoscopy or EGD), where a flexible tube with a camera is used to visualize the stomach lining and obtain biopsies of suspicious areas. Additional tests may include imaging studies like CT scans, PET scans, and endoscopic ultrasound (EUS) to assess the extent of the disease.
