Gastric Cancer
Histology and Types
>90% of gastric cancers are adenocarcinoma [Ref]
Less common types:
- Neuroendocrine tumours
- GI stromal tumours
- Lymphomas
Aetiology
H. pylori infection is the single most important risk factor for gastric cancer. [Ref1][Ref2]
Other risk factors include: [Ref1][Ref2]
- History of gastric ulcer
- EBV infection
- Smoking
- Heavy alcohol use
- High salt intake (esp. smoked, salted and pickled foods)
- GORD / Barrett’s oesophagus (associated with GOJ / cardia cancers)
- Pernicious anaemia
Clinical Features
Gastric cancer is often asymptomatic in early stages, most patients present with locally advanced or metastatic disease.
If symptomatic: [Ref]
- Weight loss
- Upper abdominal pain / discomfort
- Nausea
- Anorexia
- Dysphagia (more prominent with cardia / GOJ tumours)
- GI bleeding → haematemsis / melena
- Early satiety
- Iron deficiency anaemia
Classic signs of gastric cancer: [Ref]
- Virchow’s node (spread to the left supraclavicular lymph node)
- Sister Mary Joseph’s node (periumbilical nodule from peritoneal spread)
- Acanthosis nigricans
Red Flags and Referral
| Refer via a suspected cancer pathway |
|
| Consider referring via a suspected cancer pathway | Upper abdominal mass consistent with stomach cancer |
| Consider non-urgent, upper GI endoscopy |
|
Investigation and Diagnosis
Gold standard: upper GI endoscopy to allow direct visualisation and biopsy [Ref]
- Signet ring cells are a classic biopsy finding in gastric cancer, but specifically characteristics of the diffuse histological subtype
Staging: [Ref]
- Endoscopic ultrasound allows local staging
- CT TAP or PET/CT is used to assess metastasis and perform full staging
Management
Key management principles: [Ref]
| Stage | Management approach |
|---|---|
| Early local disease | Endoscopic resection or surgery |
| Locally advanced disease | Neoadjuvant systemic therapy followed by surgery |
| Distant metastasis | Systemic therapy: chemotherapy and/or immunotherapy (based on receptor status) |