Gastric carcinoma

Question 1

How common is gastric cancer?

Answer 1

4th most common cancer worldwide ;

8th in UK

Question 2

Who does gastric cancer affect?

Answer 2

Men; Japan; Eastern Europe; China; South America

Question 3

How is the pattern of proximal and distal gastric cancer incidence changing?

Answer 3

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)

Question 4

What are the risk factors of gastric cancer?

Answer 4

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

Question 5

There are two types of gastric cancer. Describe Intestinal (type 1) gastric cancer

Answer 5

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

Question 6

There are two types of gastric cancer. Describe Diffuse (type 2) gastric cancer

Answer 6

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

Question 7

What are the symptoms of gastric cancer?

Answer 7

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)

Question 8

What are the signs of late-stage/incurable gastric cancer?

Answer 8

Epigastric mass + tenderness
Hepatomegaly
Jaundice
Ascites  
Enlarged left supraclavicular (virchow's) node = Trosier's sign
Acanthosis nigracans 
Dermatomyositis 
Metastases to bone, brain and lung

Question 9

What is the route of spread for gastric cancer?

Answer 9

Local
Lymphatic
Blood borne
Transcoelomic ie to ovaries

Question 10

How do you diagnose gastric cancer?

Answer 10

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

Question 11

Which classification system is used for gastric cancer?

Answer 11

TNM ; tumour, nodes, metastases

Question 12

What is the management/treatment of early gastric cancers?

Answer 12

Early non-ulcerated mucosal lesions removed endoscopically.

Question 13

What is the management/treatment of advanced gastric cancers?

Answer 13

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

Question 14

What are the gastrointestinal stroll tumours (GIST)?

Answer 14

GISTs are GI mesenchymal tumours of stromal origin.

Grow slowly & may be malignant.

They are asymptomatic & found by chance - can sometimes bleed and ulcerate.

Question 15

How is GIST treated?

Answer 15

Surgery

Question 16

What is Mucosa-associated lymphatic tissue (MALT) lymphoma?

Answer 16

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.

Question 17

What causes MALT lymphomas?

Answer 17

H. pylori infection (90%)
Chromosome abnormalities (rare)

Question 18

What are the clinical features of MALT lymphomas?

Answer 18

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.

Question 19

How do you manage MALT lymphomas?

Answer 19

Eradicate H. pylori infection

Stage 3/4 disease treated with surgery or chemotherapy ± radiation.

Prognosis is good.

Question 20

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.

Answer 20

Hyperplastic polyps: most common, <2cm, rarely pre-malignant but may be present with pre-malignant atrophic gastritis.

Question 21

Which type of polyp is linked to gastric cancer? Describe this.

Answer 21

Adenomatous polyps: solitary lesions in antrum, can progress to gastric cancer especially if >2cm.

Question 22

Describe cystic gland polyp, its location and who it commonly affects.

Answer 22

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.

Question 23

Which type of polyp can become enlarged and obstruct?

Answer 23

Inflammatory fibroid polyps: benign spindle cells tumours infiltrated with eosinophils.

Can become large & obstruct - need to be removed.