GI cancer Flashcards
cancers of the GI tract
Splenic – less Liver – frequent Small bowel tumour – less Large – more parotid gland salivary gland oesophagus stomach pancreas rectum anus appendix LI duodenum gall bladder
why is cancer important
it is common - so is GI specifically
serious - causes a lot of deaths
it is what people are the most worried about
what is cancer
a disease caused by an uncontrolled division of abnormal cells in a part of the body
primary cancer
arising form cells in an organ directly
secondary/met
spread from another organ
direct invasion/metastasis
is GI cancer primary or secondary
bowel - primary
liver - secondary - blood supply
types of epithelial cells and their location
Squamous – oesophagus and rectum
Glandular epi – most of the way through
epithelial cancers
Squamous Cell Carcinoma
Adenocarcinoma
gastrinmtestinal tumours
benign
connective tissue and their canccers
Smooth muscle - Leiomyoma/leiomyosarcomas
Adipose tissue - Lipomas
neuroendocrine cells ands their tumours
Enterochromaffin cells - Carcinoid tumours
Interstitial cells of Cajal - Gastrointestinal Stromal Tumours
most common GI tumour
adenocarcinoma
what things do you need to ask someone who has dysphagia (difficulty swallowing)
Textures of what people can swallow
obstruction/failure in peristaltic mechanisms
Cancer – progressive, start with big bits and then to yoghurts whereas Neuromuscular – spontaneously cant do both
Vom – food cant even get down tubv
Weight loss – is worrying, not getting any food
what are risk factors for oesophageal cancer
previous reflux, overweight, smoking, alcohol
where is columnar epithelium in the oesophagus
near stomach
muscle through the oesophagus
progresses from skeletal to smooth
describe oesophageal cancer
From metaplastic columnar epithelium
Lower 1/3 of oesophagus
Related to acid reflux = recurrent damage to mucosa from acid
More developed world = obesity
why is being overweight a risk factor for acid reflux
increase abdominal pressure = force food back up
describe squamous cell carcinoma
From normal oesophageal squamous epithelium
Upper 2/3
Acetaldehyde pathway - increased by smoking and alcohol = damage epi
Less developed world - mutations in acetaldehyde dehydrogenase enzyme = build up of metabolite - increase risk of cancer
symptoms of acid reflux
Long history of heart burn, regurgitation and burping - stimulate oesophagus, swallow air - reflux = it comes back up
describe endoscopy
Pass tube down mouth – visually see oesophagus and stomach
Conscious
how does acid reflux progress to cancer
chronic exposure to acid injury, ongoing inflammation, cytokine drive 15% pop have GORD 5-13% of them - Barrett's (metaplasia) 5% per year - dysplasia 0.5%-30% - carcinoma - neoplasia
barretts oesophagus
expression of cells where not normal eg columnar where expect to see squamous
metaplasia
barretts oesophagus on endoscopy
Red- columnar
Black hole – gastroesophageal junction
risk factors for colorectal cancer
Family History - has to be really strong, first degree relatives <50yrs
Specific inherited conditions
FAP (Familial adenomatous polyposis), HNPCC (hereditary nonpolyposis colorectal cancer), Lynch Syndrome
Uncontrolled Ulcerative Colitis
Age
Previous Polyps
histology of adenocarcinoma
densification of tissue
describe the progression to colorectal cancer
- inhibited by NSAIDSs, folate ca. caused by APC mutation -> hyperproliferative epithelium, abberent cryptic foci
- inhibited by NSAIDSs -> small adenoma
- inhibited by NSAIDSs and oestrogen, casued by K-ras nmutation -> large adenoma
- casued bt p53 mutation and loss of 18q -> colon cancer
appearance of polyps as the progess
secile - on the epi lining
pedunculated
Necrotic area – black and white bits – definitely colorectal
pathology of colorectal cancer
not single gene
sequence fo genetic errors - APC< K-ras, p52, 18q
affects the risk factors
symptoms of colorectal cancers
Asymptomatic (incidental anaemia) - routine blood test Change in Bowel Habit Diarrhoea more than constipation Blood in Stool Acute intestinal obstruction weight loss loss of appetite nausea and vomiting rectal bleeding anaemia
symptoms that are not associated with colorectal cancer
Rectal bleeding with anal symptoms - Itch, Soreness / discomfort, External lump, prolapse
constipation alone
abdominal pain with no obstruction
use of x ray to diagnose colorectal cancer
Cant see the bowel
there is stifling appearance so proberly poo = constipation
+ cheap, easy, quick
- low sensitivity and specificity, No use to pick up early disease
use of plane CT to diagnose colorectal cancer
+ Quick
Easy
See large lesions
- May miss smaller lesions
No tissue = No therapy
process of barium enema
barium liquid is instilled in LI, patient move around, then viewed
Can do double – air next time – colon expand – see better
barium enema for colorectal cancer
+ Reasonable Sensitivity and Specificity
- Time Intensive
Technically demanding
Unacceptable to patients
process of colonoscopy
Pump it all the way round
recognise caecum by - appendix, ileoceacal valve, triradiate folds
Difficult to move rigid tube though a tube that moves
end of tube: video chip, irrigation channel, instrument channel - allow take samples, light
colonoscopy for colorectal cancer
\+ Safe Relatively quick High Sensitivity Able to obtain tissue - 2 days of iatrogenic diarrhoea Small risk of perforation (<1:2000) Risk of dehydration
process of CT virtual colonoscopy
Give something similar to barium – drink
Put them in CT
“tag” stool using Bismuth
Technology to remove poo from bowel from the wall
CT virtual colonoscopy for colorectal cancer
+Quick
Easy
Reduced Bowel prep more tolerable
As good as colonoscopy for lesions >6mm
- unable to get tissue
cant remove lesion
way to remove bleed
Current to burn through bv – so that the vessel doesn’t bleed – pick up polyp and take away
Inject saline into wall – lift it away from wall – snair to remove it from the wall
Scar will heal after day/2
problem with diagnosing pancreatic cancer
silent killer
non-specific
Virchow’s traid - pain, anorexia, weight loss - Not a massive proportion of patients `
early symptoms of pancreatic cancer
Abdominal pain
Depression
Glucose intolerance - worry about the effect on the pancreas
late symptoms of pancreatic
Weight loss
Jaundice
Ascites
Obstructed gall bladder
- too late
outcome of pancreatic cancer
poor surgery curative on 20-25% cases 1 year survival 18% 5 year 2% only 20% suitable for resection
describe the surgery for pancreatic cancer
take away panc, duodenum,, gall bladder - put everything else back after
risk factors for pancreatic cancer
Smoking Drinking Obesity Family Especially rare conditions such as MEN - Presents with cancer in family with different sites
describe adenocarcinoma
from metastatic columnar epi lowe 1/3 oesophagus acid reflux - repeated damage to oesophagus related to obesity developed world
is adenocarcinoma more frequent in men or women
men
because of hormonal control in women
list the phases in the progression of ADENOCARCINOMA
Normal epithelium
Hyperplasia - abnormal proliferation of epithelial cells
Development of adenomatous polyps
Development of adenocarcinoma
Metastasis
list the phases in the progression of SQUAMOUS cell carcinoma
Normal epithelium
Metaplasia - development of abnormal squamous cell
Dysplasia - proliferation of abnormal cells
Severe dysplasia - almost all cells are abnormal
Development of squamous cell carcinoma
Metastitsis
symptoms of oesophageal cancer
when >50% circumference of oesophagus is cancerous - narrowing of the tube
- Difficulty and pain when swallowing
Weight loss - due to lack of nutrition
Pain in the breast bone and stomach, or a feeling of reflux
later symptoms: Nausea, vomiting, and regurgitation of food
Vomiting blood, due to trauma to the tumour
what does a CT check for
metastasis
treatment of oesophageal cancer
surgery - tumour removed from oesophageal wall
oesophagectomy - remobval of part of the oesophagus
chemo and radiotherapy
cause of colorectal cancer
diet
alcohol
tobacco
lack of physical activity
treatment of colorectal cancer
surgery - removal of tumour via colonscopy or laparotomy
may result in removal of large parts of colon = colonstomy
chemo and radiotherapy
