Can Endoscopy Detect Stomach Cancer?
Yes, upper endoscopy (esophagogastroduodenoscopy) with biopsy is the gold standard diagnostic test for detecting stomach cancer and remains the investigation of choice for diagnosis. 1, 2
Diagnostic Accuracy and Role
Video endoscopy with endoscopic biopsy is the definitive diagnostic test that must be performed by an experienced endoscopist before any treatment can be initiated. 1, 2 The British Society of Gastroenterology and European guidelines establish that histopathological examination via endoscopic biopsy is mandatory and represents the gold standard for gastric cancer diagnosis. 2
Detection Capabilities
- Endoscopy can detect both early and advanced gastric cancer, though approximately 70% of patients with early gastric cancer present with only uncomplicated dyspepsia without alarm symptoms like anemia, dysphagia, or weight loss. 1
- The procedure allows direct visualization of suspicious lesions and enables tissue sampling for histopathological confirmation according to WHO criteria. 2
- Enhanced imaging techniques including narrow-band imaging and magnification endoscopy improve characterization of suspicious lesions during the procedure. 3
Important Limitations and Pitfalls
Endoscopy can miss gastric cancer in 10% of cases at the first examination, with an additional 10-20% of patients requiring repeat gastroscopy. 1 The principal factors causing missed diagnoses are:
- Failure to suspect malignancy based on visual appearance 1
- Failure to take adequate numbers of biopsies from suspicious areas 1
- Cancers located in difficult-to-visualize areas (cardia, greater curvature of the body) 4
- Diffuse-type or signet ring cell adenocarcinomas that may have subtle endoscopic appearances 4
Critical Technical Requirements
To maximize detection rates, the endoscopist must obtain multiple biopsies from any suspicious lesion—the diagnostic yield reaches 100% when six or more samples are obtained. 1 Additional requirements include:
- Systematic examination protocol covering the entire stomach, including blind spots 5
- Administration of antiperistaltic agents for optimal visualization 3
- Stopping proton pump inhibitors (PPIs) before the first endoscopy, as PPIs can mask endoscopic findings and heal malignant ulcers, potentially causing misdiagnosis. 1
- Photographic documentation of all lesions 1
Who Should Undergo Endoscopy
Patients over 55 years with new-onset dyspepsia or any patient with alarm features at any age should undergo endoscopy. 1 Specific indications include:
- Dysphagia (difficulty swallowing) at any age 1, 6
- Unintentional weight loss at any age 1, 6
- Anemia at any age 1, 6
- Persistent vomiting 1, 6
- New-onset dyspepsia in patients ≥55 years 1
However, clinical diagnosis is very inaccurate, and endoscopy should be considered even in the absence of alarm features when there is clinical suspicion of malignancy. 1 Research demonstrates that high-risk symptoms predict gastric cancer (OR 1.8) but fail to predict precursor lesions like gastric intestinal metaplasia. 7
What Happens After Cancer Detection
Once gastric cancer is confirmed by endoscopy and biopsy:
- All specimens must be reviewed by an experienced pathologist and reported according to WHO criteria. 2
- HER2 status must be assessed on all gastric or esophagogastric junction adenocarcinomas for treatment planning. 2
- Contrast-enhanced CT of chest, abdomen, and pelvis becomes the primary staging modality. 2, 8
- Endoscopic ultrasound (EUS) provides accurate T and N staging with sensitivity of 0.86 and specificity of 0.90 for distinguishing T1/2 from T3/4 tumors. 2
- Diagnostic laparoscopy with peritoneal washings is recommended for stage IB-III disease to detect occult peritoneal metastases. 2
When to Repeat Endoscopy
If a patient continues to have upper gastrointestinal symptoms despite a negative endoscopy, repeat endoscopy and/or additional diagnostic studies should be strongly considered, as even advanced gastric cancer can be missed. 4 This is particularly important for: