Gastric cancer Flashcards
Who gets gastric cancer
Elderly
Men 2:1 women
Risk factors for gastric cancer
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
How can H pylori cause gastric cancer
Chronic inflammation ->
Promotes cellular proliferation, angiogenesis and tissue remodelling
-> atrophic gastritis -> intestinal metaplasia -> dysplasia -> adenocarcinoma
Key molecular and cellular mechanisms in cancer
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
Classifying gastric cancer
Histology - Laurens classification - intestinal or diffuse
TCGA molecular 4 subtypes
Anaomty - proximal or distal
Intestinal gastric cancer features
Cohesive, gland forming cells ass w environemtnal factors eg H pylori and dietary habits
Diffuse gastric cancer features
Poorly differentiated discohesive cells - genetic predisposition
Worse prognosis than intestinal
Molecular subtypes of gastric cancer
EBV +
Microsatellite instability - MSI
Genomically stable - GS
Chromosome instability - CIN
Clinical features of gastric cancer
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).
When do you refer someone for gastric cancer
Upper abdominal mass consistent w gastric cancer
When offer urgent direct access upper GI endsocopy to assess for stomach cancer
Dysphagia
>55 with weight loss and any of:
-upper abdo pain
-reflux
-dyspepsia
When consider endoscopy t assess for stomach cancer
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
Investigations for gastric cancer
Endoscopy with biopsy
CT or ensodcopic US for staging
Laparoscopy - occult peritoneal disease
PET CT
Surgical options for gastric cancer
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
How can chemotherapy be delivered in gastric cancer
Neoadjuvant chemotherapy
Adjuvant chemotherapy
Palliative chemotherapy
Common chemoterhapies used in gastric cancer
Flurorpyrimidibes - 5FUU, capecitabine
Plaitnum compunds - cisplatin, oxaplatin
Taxans - paclitacel, docetaxel
What tumours are trastuzumab or pertuzumab used in
HER2 positive tumours in combo w chemo
Anti HER2
When is anti-VEGF therapy used in gastric cancer
Advance metastatic disease - targets vascular endothelial growth factor ef ramucirumab
What medication can be used in microsatellite instability high or PDL1 + tgastric tumours
Immune checkpoint inhibitors eg pembrolizumab,nivolumab
Complications of gastric cancer
Obstruction -> vomitting, malnutrition and dehydration
Perforation
Metastasis
Treatment related complicaitons
Stage IA to IIIA prognosiss gastric cancer
IA - 90-95%
IB - 85-90
IIA - 70-80-
IIB - 55-65%
IIIA - 40-50%
IIIB - 25-35%
IIIC - 10-20%
IV <5%
What lymph nodes may be affected in gastric ccancer
Virchows
L axillary
Cervical
What is hereditary tylosis
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
what is plummer vinson syndrome
Rare condition triad of dysphagia, Iron defA, oesophageal webs (thin membranous structures can block oesophagus)
Cause and treatment of plummer-vinsoin syndrome
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
What is blumer’s shelf
Palpable finding in rectal or vaginal exam indicating tumour has metastasised into puch of douglas
What is a krukenberg tuymour
Ovarian tumour originating through metastases
Stomach cancer esp signe tcell adenocqarcinoma common
