Gastric carcinoma Flashcards
How common is gastric cancer?
4th most common cancer worldwide ;
8th in UK
Who does gastric cancer affect?
Men; Japan; Eastern Europe; China; South America
How is the pattern of proximal and distal gastric cancer incidence changing?
Incidence of proximal gastro-oesophageal junction cancer is increasing in West (linked to Barrett’s)
Incidence of distal and gastric body carcinoma has decreased (linked to reduction in H. Pylori infection & better food storage)
What are the risk factors of gastric cancer?
Pernicious anaemia (due to accompanying atrophic gastritis), Blood group A, H. pylori, Atrophic gastritis, Adenomatous polyps (3%), Lower social class, Smoking, Diet (high nitrate, salt, low Vit C), Nitrosamine exposure, First degree relative
There are two types of gastric cancer. Describe Intestinal (type 1) gastric cancer
Well formed glandular structures (differentiated)
Polypoid or ulcerative regions with rolled edges
Intestinal metaplasia in surrounding structures with H.Pylori
Distal stomach
Can occur in patients with atrophic gastritis
Strong environmental associations
There are two types of gastric cancer. Describe Diffuse (type 2) gastric cancer
Poorly cohesive cells (undifferentiated) infiltrate the gastric wall.
Involves any part of the stomach, esp the cardia
Worse prognosis than the intestinal type
Loss of expression of the cell adhesion molecule E-cadherin => cancer
Occurs in younger population
What are the symptoms of gastric cancer?
Most patients have advanced disease at presentation.
Half of patients with early gastric cancer discovered at screening have no symptoms.
Symptoms:
Epigastric pain - vary in intensity but constant and severe
Nausea & vomiting (can be severe if tumour encroaches pylorus)
Weight loss & anorexia
Dysphagia (tumours in fundus)
What are the signs of late-stage/incurable gastric cancer?
Epigastric mass + tenderness Hepatomegaly Jaundice Ascites Enlarged left supraclavicular (virchow's) node = Trosier's sign Acanthosis nigracans Dermatomyositis Metastases to bone, brain and lung
What is the route of spread for gastric cancer?
Local
Lymphatic
Blood borne
Transcoelomic ie to ovaries
How do you diagnose gastric cancer?
Gastroscopy + multiple ulcer edge biopsies for histology
Endoscopic ultrasound - for depth of tumour invasion
CT/MRI - staging of cancer
Staging laparoscopy - for locally advanced tumours
Cytology of peritoneal washings for peritoneal metastases
Which classification system is used for gastric cancer?
TNM ; tumour, nodes, metastases
What is the management/treatment of early gastric cancers?
Early non-ulcerated mucosal lesions removed endoscopically.
What is the management/treatment of advanced gastric cancers?
Surgery = best cure - patients need to be carefully selected (fit for surgery etc to prolong survival rates)
Partial gastrectomy for advanced distal tumours.
Total gastrectomy for proximal tumours
± chemoradiotherapy
What are the gastrointestinal stroll tumours (GIST)?
GISTs are GI mesenchymal tumours of stromal origin.
Grow slowly & may be malignant.
They are asymptomatic & found by chance - can sometimes bleed and ulcerate.
How is GIST treated?
Surgery
What is Mucosa-associated lymphatic tissue (MALT) lymphoma?
MALT lymphoma is a primary gastric lymphoma.
MALT affects the mucosa.
MALT lymphomas are B-cell marginal zone lymphomas that involves sites other than lymph nodes ie GI tract, thyroid, breast or skin.
MALT lymphomas make up 10% of all non-Hodgkin’s lymphomas.
What causes MALT lymphomas?
H. pylori infection (90%) Chromosome abnormalities (rare)
What are the clinical features of MALT lymphomas?
Patients diagnosed in 60’s with Stage 1 or 2 of disease.
Stomach pain, ulcers & other localised symptoms.
Rarely systemic symptoms i.e. fatigue or fever.
How do you manage MALT lymphomas?
Eradicate H. pylori infection
Stage 3/4 disease treated with surgery or chemotherapy ± radiation.
Prognosis is good.
Gastric polyps are found by chance, rarely symptomatic but larger lesions can result in anaemia or haematemesis. There are 4 types of polyps.
What is the most common type of polyp? Describe this.
Hyperplastic polyps: most common, <2cm, rarely pre-malignant but may be present with pre-malignant atrophic gastritis.
Which type of polyp is linked to gastric cancer? Describe this.
Adenomatous polyps: solitary lesions in antrum, can progress to gastric cancer especially if >2cm.
Describe cystic gland polyp, its location and who it commonly affects.
Cystic gland polyps: micro cysts that are lined by parietal & chief cells, located in fundus & body of the stomach.
Found in healthy people but common in familial polyposis syndromes & patients on PPI.
Which type of polyp can become enlarged and obstruct?
Inflammatory fibroid polyps: benign spindle cells tumours infiltrated with eosinophils.
Can become large & obstruct - need to be removed.
