Gastric Cancer ✅

Related Subjects: |Upper Gastrointestinal Bleed |Oesophageal Variceal Bleeding |Dieulafoy Lesion |Mallory-Weiss Tear |Gastric Cancer |Peptic Ulcer Disease |Oesophagogastroduodenoscopy (OGD/EGD) |Hereditary Haemorrhagic Telangiectasia |Hypovolaemic or Haemorrhagic Shock

📈 Proximal gastric and oesophagogastric junction (OGJ) tumours have become relatively more prominent, while distal gastric cancers have declined in many Western populations. 🍽️ Gastric cancer is still an important cause of cancer death worldwide, although incidence in the UK is much lower than for common cancers such as bowel, breast, lung, and prostate.

📖 About

• Most gastric cancers are adenocarcinomas arising from the gastric mucosa.
• In the UK, stomach cancer accounts for about 2% of new cancers and has an overall 5-year survival of around 20%.
• It is more common in older adults and in men.
• NICE manages this under the broader oesophago-gastric cancer pathway.

🔬 Histological Types

• Adenocarcinoma – by far the commonest type.
• Lauren classification: intestinal type vs diffuse type.
• Lymphoma – especially MALT lymphoma, often linked to chronic H. pylori.
• GIST – mesenchymal tumour, often KIT (CD117) positive.
• Neuroendocrine neoplasms – rare gastric tumours arising from neuroendocrine cells.

🧪 Pathology

• Macroscopic patterns: ulcerating, polypoid, or infiltrative lesions.
• Linitis plastica = diffuse infiltrative adenocarcinoma causing a rigid “leather bottle” stomach.
• Spread routes:
  • Direct: adjacent structures such as pancreas, transverse colon, and liver.
  • Lymphatic: perigastric and coeliac nodes; may present with Virchow’s node.
  • Haematogenous: especially liver and lung.
  • Transcoelomic: peritoneum and ovaries (Krukenberg tumour).

🌍 Epidemiology

• Incidence is highest in parts of East Asia, Eastern Europe, and South America.
• In the UK, the cardia is now the commonest specific stomach subsite recorded.
• Declining distal gastric cancer is linked to changes in food preservation and reduced H. pylori burden.

⚠️ Risk Factors

• 🦠 H. pylori infection → chronic gastritis → atrophy / intestinal metaplasia → dysplasia → carcinoma.
• 🥓 Diet: high salt and preserved/smoked foods; lower fruit and vegetable intake increases risk.
• 🚬 Smoking increases risk.
• 👨‍👩‍👧 Family / genetics: including CDH1-associated hereditary diffuse gastric cancer.
• 🔥 Chronic gastritis / atrophy: including autoimmune gastritis and pernicious anaemia.
• ⚖️ Older age and male sex.
• 🌡️ Reflux / obesity are particularly relevant around the OGJ region.

🩺 Clinical Features

• Dyspepsia, epigastric discomfort, early satiety.
• Anorexia, unintentional weight loss, fatigue.
• Nausea or vomiting, especially if there is gastric outlet obstruction.
• Upper GI bleeding: melaena or haematemesis.
• Iron-deficiency anaemia may be a presenting clue.
• Advanced signs:
  • Virchow’s node (left supraclavicular).
  • Sister Mary Joseph nodule.
  • Ascites or jaundice from metastatic disease.
  • Palpable epigastric mass.

🔎 Investigations

• OGD with biopsy = diagnostic test.
• Histology confirms tumour type.
• CT chest/abdomen/pelvis = initial staging investigation after diagnosis.
• Staging laparoscopy should be offered for potentially curable gastric cancer.
• Endoscopic ultrasound may be considered if it will help guide management.
• PET-CT is not routine for all gastric cancers; it is considered if metastatic disease is suspected and results would alter management.
• Bloods: FBC, U&E, LFTs, nutritional status. Tumour markers are not diagnostic.
• HER2 testing should be performed in metastatic oesophago-gastric adenocarcinoma.

🚑 Complications

• Chronic blood loss → iron-deficiency anaemia.
• Gastric outlet obstruction → persistent vomiting and dehydration.
• Metastatic spread to liver, peritoneum, lung, and ovary.
• After gastrectomy: vitamin B12 deficiency, iron deficiency, weight loss, and dumping syndrome.

🛠️ Management

• MDT care in a specialist oesophago-gastric cancer service is essential.
• Curative treatment depends on site and stage:
  • Gastric cancer: subtotal or total gastrectomy depending on tumour location and extent.
  • OGJ tumours: surgical approach depends on exact junctional location and specialist MDT planning.
  • When performing curative gastrectomy, consider D2 lymph node dissection.
• Peri-operative treatment:
  • For gastric cancer having radical resection, offer chemotherapy before and after surgery.
  • For localised oesophageal / OGJ adenocarcinoma planned for surgery, offer a choice of chemotherapy before or before-and-after surgery or chemoradiotherapy before surgery.
• Palliative care: systemic therapy, dietetic support, stenting or surgery for obstruction, symptom control, and palliative care input.
• Gastric outlet obstruction: consider uncovered self-expanding metal stents or palliative surgery depending on prognosis and fitness.
• MALT lymphoma may respond to H. pylori eradication because its management differs from adenocarcinoma.

📊 Prognosis

• Overall UK outcomes remain poor because many cases present late.
• Earlier-stage disease has a much better prognosis than metastatic disease.
• Diffuse type, linitis plastica, nodal spread, and distant metastases worsen prognosis.

📚 Teaching Commentary

🩺 Exam pearls:
– Virchow’s node + weight loss → think gastric malignancy.
– Linitis plastica = classic infiltrative diffuse-type adenocarcinoma with a “leather bottle” stomach.
– Krukenberg tumour = ovarian metastasis, classically from signet-ring adenocarcinoma.

💡 UK/NICE pearls:
– Always say OGD with biopsy for diagnosis.
– For potentially curable gastric cancer, remember CT staging + staging laparoscopy.
– Mention specialist MDT care, peri-operative chemotherapy, and dietetic support.
– There is no UK population screening programme for gastric cancer.