What is the recommended process for staging gastroesophageal junction (GEJ) cancer?

Staging Gastroesophageal Junction Cancer

Staging of gastroesophageal junction (GEJ) cancer requires a systematic multimodal approach beginning with CT chest/abdomen/pelvis with contrast, followed by endoscopic ultrasound (EUS) for T and N staging, and PET-CT to detect occult distant metastases, with laparoscopy added for locally advanced tumors to exclude peritoneal disease. 1

Initial Diagnostic Requirements

Before staging can proceed, you must establish the diagnosis and tumor classification:

• Perform upper endoscopy with a minimum of six biopsies to confirm histologic diagnosis and document tumor location relative to the anatomic cardia using the Siewert classification system 2, 1
• Document tumor length, circumferential involvement, degree of obstruction, and distance from incisors during endoscopy 1
• Obtain complete blood count, liver function tests, and renal function tests to assess treatment eligibility 1
• Confirm histologic type per WHO criteria to distinguish adenocarcinoma from squamous cell carcinoma, as treatment differs fundamentally 1

Staging Algorithm: Step-by-Step Approach

Step 1: Cross-Sectional Imaging (First-Line)

• CT of chest, abdomen, and pelvis with oral and IV contrast is the primary staging modality to identify distant metastases 2, 1
• Use multiplanar reconstructions to improve accuracy 2
• Ensure the gastric cavity is fully dilated by having the patient drink 500 mL of water prior to examination 2
• Plain CT scans without contrast are inadequate and not recommended 2

Step 2: Endoscopic Ultrasound

• Perform EUS with fine-needle aspiration to evaluate T and N stage, particularly for surgical planning 2, 1
• EUS is the preferred modality for clinical T staging according to the AJCC/UICC 8th edition staging system 2
• EUS has overall sensitivity and specificity of 0.86 and 0.90 for distinguishing T1/2 from T3/4 cancers 2
• EUS can detect enlarged perigastric lymph nodes and metastatic lesions in liver and peritoneal cavity 2
• Important caveat: EUS is not helpful for detailed staging of mucosal disease 2

Step 3: PET-CT for Comprehensive Staging

• Add PET-CT (not PET alone) to CT and EUS for comprehensive staging, as it identifies occult distant metastases in approximately 15-20% of cases 1
• PET-CT should be used in combination with EUS and CT for assessment of GEJ cancer 2
• This modality is particularly valuable for detecting systemic metastases 2

Step 4: Laparoscopy for Selected Cases

• Perform diagnostic laparoscopy for all locally advanced (cT3/4) tumors to detect occult peritoneal metastasis 2
• Laparoscopy should be undertaken in selected patients with lower esophageal and GEJ tumors 2
• During laparoscopy, infuse 200 mL of normal saline into different quadrants of the abdominal cavity and collect more than 50 mL of lavage fluid for cytological examination 2

Step 5: Additional Imaging When Indicated

• If liver metastasis is suspected on CT, obtain abdominal MRI for further confirmation 2
• Use hepatocyte-specific contrast agents to increase diagnostic sensitivity when patient conditions permit 2
• For T1 esophageal tumors or nodularity in high-grade dysplasia, perform staging by endoscopic resection to define depth of invasion 2

Critical Staging Measurements

When interpreting imaging studies, use these thresholds:

• Nodules of liver, lung, or peritoneal metastasis with long-axis diameter ≥1 cm should be considered metastatic 2
• Lymph nodes with short-axis diameter ≥1.5 cm should be considered pathologic 2

Common Pitfalls to Avoid

• Do not rely on chest X-rays alone—chest CT detects and shows lung metastasis better than X-rays 2
• Do not skip chest CT for GEJ tumors—an enhanced CT scan of the chest is essential to judge the range and metastatic status of mediastinal lymph nodes 2
• Do not perform EUS at non-specialized centers—EUS should only be carried out in qualified centers 2
• Do not use plain abdominal CT scans—enhanced contrast scans are required; if contraindications to contrast exist, use MRI or EUS instead 2

Coordination and Quality Standards

• All staging investigations must be coordinated within an agreed pathway led by an upper GI multidisciplinary team (MDT) 2, 1
• Every patient must be discussed in an upper GI MDT before initiating treatment 1
• Imaging reports should describe observations to support clinical stage evaluation and classification (cTNM) 2

Molecular and Biomarker Assessment

• All cases of GEJ adenocarcinoma should undergo HER2 assessment, as this is the basis for selecting anti-HER2 targeted therapy 2, 3
• HER2-neu testing is essential if metastatic disease is documented or suspected, as it directly impacts treatment selection 3