Gastric cancer

Question 1

Who gets gastric cancer

Answer 1

Elderly
Men 2:1 women

Question 2

Risk factors for gastric cancer

Answer 2

H.PYLORI - primary (75% cases)
Diet - high salt intake, consumption of smoke or preserved foods, low fruit and veg intake
Smoking
Alcohol consumption
Pernicious anaemia and atrophic gastritis
FH gastric cancer
Genetic syndromes - hereditary diffuse gastric cacner, lynch syndrome

Question 3

How can H pylori cause gastric cancer

Answer 3

Chronic inflammation ->
Promotes cellular proliferation, angiogenesis and tissue remodelling
-> atrophic gastritis -> intestinal metaplasia -> dysplasia -> adenocarcinoma

Question 4

Key molecular and cellular mechanisms in cancer

Answer 4

Activation of oncogenes - ERB2, MET, FGFR2
Inactivation of tumour supressor genes - TP53, CDH1, RUNX3
dYSREGULATION OF cell cycle control - CCND1, CDKN2A
Disruptio of DNA repair mechanisms - BRCA1,BRCA2, MSH2, MLH1
Epigenetic modifications eg DNA methylation, histone modifications, non coding RNAs

Question 5

Classifying gastric cancer

Answer 5

Histology - Laurens classification - intestinal or diffuse
TCGA molecular 4 subtypes
Anaomty - proximal or distal

Question 6

Intestinal gastric cancer features

Answer 6

Cohesive, gland forming cells ass w environemtnal factors eg H pylori and dietary habits

Question 7

Diffuse gastric cancer features

Answer 7

Poorly differentiated discohesive cells - genetic predisposition
Worse prognosis than intestinal

Question 8

Molecular subtypes of gastric cancer

Answer 8

EBV +
Microsatellite instability - MSI
Genomically stable - GS
Chromosome instability - CIN

Question 9

Clinical features of gastric cancer

Answer 9

Dyspepsia or indigestion
Epigastric pain
Early satiety or postprandial fullness
Weight loss
Anaemia
N+V
GI bleeding - melaena, haematemesis
Advanced disease ->
palpable abdominal mass, ascites, and supraclavicular lymphadenopathy (Virchow’s node).

Question 10

When do you refer someone for gastric cancer

Answer 10

Upper abdominal mass consistent w gastric cancer

Question 11

When offer urgent direct access upper GI endsocopy to assess for stomach cancer

Answer 11

Dysphagia
>55 with weight loss and any of:
-upper abdo pain
-reflux
-dyspepsia

Question 12

When consider endoscopy t assess for stomach cancer

Answer 12

Anyone with haematemesis

> 55 and:
treatement resistant dyspepsia or
upper abdo pain with low Hb or
Raised platelet count with any of the following:
-N
-V
-weight loss
Reflux
Dyspepsia
Upper abdo pain

N/V w any of:
-Weight loss
-Reflux
-Dyspepsia
-Upper abdo pain

Question 13

Investigations for gastric cancer

Answer 13

Endoscopy with biopsy
CT or ensodcopic US for staging
Laparoscopy - occult peritoneal disease
PET CT

Question 14

Surgical options for gastric cancer

Answer 14

For localcised gastric cancer
Partial gastrectomy - removal of portion of stomach - early stage localised tumours
Total gastrectomy - removal of entire stomach
Lymph node dissection - D1 or D2 - performed according to tumour stage and location. Minimally invasive tecxhniques or robot assisted may be used

Question 15

How can chemotherapy be delivered in gastric cancer

Answer 15

Neoadjuvant chemotherapy
Adjuvant chemotherapy
Palliative chemotherapy

Question 16

Common chemoterhapies used in gastric cancer

Answer 16

Flurorpyrimidibes - 5FUU, capecitabine
Plaitnum compunds - cisplatin, oxaplatin
Taxans - paclitacel, docetaxel

Question 17

What tumours are trastuzumab or pertuzumab used in

Answer 17

HER2 positive tumours in combo w chemo
Anti HER2

Question 18

When is anti-VEGF therapy used in gastric cancer

Answer 18

Advance metastatic disease - targets vascular endothelial growth factor ef ramucirumab

Question 19

What medication can be used in microsatellite instability high or PDL1 + tgastric tumours

Answer 19

Immune checkpoint inhibitors eg pembrolizumab,nivolumab

Question 20

Complications of gastric cancer

Answer 20

Obstruction -> vomitting, malnutrition and dehydration
Perforation
Metastasis
Treatment related complicaitons

Question 21

Stage IA to IIIA prognosiss gastric cancer

Answer 21

IA - 90-95%
IB - 85-90
IIA - 70-80-
IIB - 55-65%
IIIA - 40-50%
IIIB - 25-35%
IIIC - 10-20%
IV <5%

Question 22

What lymph nodes may be affected in gastric ccancer

Answer 22

Virchows
L axillary
Cervical

Question 23

What is hereditary tylosis

Answer 23

Genetic condition thickening of skin palms and soles and increased risk of oesophageal cancer (SCC)
RHBDF2 gene - autosomal dominant
Moisturisers and keratolytic agents and monitoring ofr oesophageal cancer w endoscopies

Question 24

what is plummer vinson syndrome

Answer 24

Rare condition triad of dysphagia, Iron defA, oesophageal webs (thin membranous structures can block oesophagus)

Question 25

Cause and treatment of plummer-vinsoin syndrome

Answer 25

Middle aged women - long term iron deficiency, nutritional factors eg low iron doet
Improve iron deficiency through supplementation
Oesopgaela dilatio for oesophafeal wens amd monitoring for cancer -SCC

Question 26

What is blumer’s shelf

Answer 26

Palpable finding in rectal or vaginal exam indicating tumour has metastasised into puch of douglas

Question 27

What is a krukenberg tuymour

Answer 27

Ovarian tumour originating through metastases
Stomach cancer esp signe tcell adenocqarcinoma common