GI Cancers Flashcards
Epithelial cancers
Squamous cell carcinoma
Adenocarcinona
Neuroendocrine cells
Enteroendocrine cells - Neuroendocrine tumours
Interstitial cells of Cajal - GI stromal tumours
Connective tissue cancers
Smooth muscle - Leiomyoma/leiomyosarcoma
Adipose tissue - Liposarcomas
Oeseophageal cancer
Squamous
- from normal oesophageal squamous epithelium
- upper 2/3
- Acetaldehyde pathway
- less developed world
Adenocarcinoma
- from metaplastic columnar epithelium
- lower 1/3 of oesophagus
- related to acid reflux
- more developed world
Reflux to cancer
Oesophagitis (inflammation) - 30% of UK population - GORD
Barrett’s (metaplasia) - 5% of GORD - Barrett’s
Adenocarcinoma (neoplasia) - Barrett’s lifetime risk of cancer - 0.5-1%/year
30-100 fold risk of cancer
Barrett’s to Cancer
Barrett’s oesophagus - dysplasia (low grade) - dysplasia (high grade) - adenocarcinoma
Barrett’s surveillance
BSG guidelines
- no dysplasia - every 2-3 years
- LGD - every 6 months
- HGD - intervention
Oesophageal cancer risk factor
Affects the elderly
Male/female - adenocarcinoma 10/1
Oesophageal cancer survival
Late presentation - dysphagia and weight loss 65% palliative High morbidity and complex surgery Poor 5 year survival <20% Palliative - difficult
Oesophageal diagnosis
Endoscopy - biopsy
Oesophageal staging
CT
Laparoscopy
Oesophageal treatment plan
Curative - neo-adjuvant chemo - radical surgery Palliative - chemo - DXT - stent
Oeseophageal management pathway
Diagnosis
Staging
Treatment plan
Oesophagectomy
Two stage ivor Lewis approach
Colorectal cancer background
Most common GI cancer in western society Lifetime risk -1 in 10 for men -1 in 14 for women Generally patients >50 years
Colorectal cancer forms
Sporadic - no family history, older population, isolated lesion
Familial - family history, high risk if index case is young (<50) and relative is close (first degree)
Hereditary syndrome - family history, younger, specific gene defects
Histopathology - adenocarcinoma
Colorectal cancer stages
APC mutation - Hyperproliferative epithelium
COX2 overexpression - Small adenoma
K-ras mutation - Large adenoma
p53 and loss of 18q - Colon carcinoma
Colorectal cancer risk factors
Past history -colorectal cancer -adenoma, ulcerative colitis, radiotherapy Family history -first degree relative <55years -relative with identified genetic predisposition Diet/environment -smoking -obesity -socioeconomic status
Colorectal cancer locations
2/3 in descending colon and rectum
1/2 in sigmoid colon and rectum (sigmoidoscopy)
Caecal and right sided cancer
Iron deficiency anemia most common Change of bowel habit (diarrhoea) Distal ileum obstruction (late) Palpable mass (late)
Left sided and sigmoid carcinoma
PR bleeding, mucus Thin stool (late)
Rectal carcinoma
PR bleeding, mucus
Tenesmus (feeling to pass stool)
Anal, perineal, sacral pain (late)
Bowel obstruction (late)
Local invasion of colon cancer
Late
Bladder symptoms
Female genital tract symptoms
Metastasis - colorectal
Late Liver (hepatic pain, jaundice) Lung (cough) Regional lymph nodes Peritoneum (sister Mary Joseph nodule)
Colorectal cancer examination
Primary
- Abdo mass
- Digital rectal examination - most <12cm dentate and reached by examining finger
- rigid sigmoidoscopy
- abdominal tenderness and distention - large bowel obstruction
Metastasis and complications
- hepatomegaly (mets)
- monophonic wheeze
- bone pain
Colorectal cancer investigations
Faecal occult blood
-faecal immunochemical test - detect minute amounts of blood in faeces (faecal occult blood)
Blood tests
- anemia, haematinics - low ferritin
- tumour markers - CEA which is useful for monitoring - not diagnostic
Colonoscopy
- can visualise lesions <5mm
- small polyps can be removed - reduce cancer incidence
- under sedation
CT colonoscopy/colonography
- can visualise lesions >5mm
- no need for sedation
- less invasive
- if lesion identified needs colonoscopy for diagnosis
Colorectal cancer imaging tests
MRI rectal - rectal cancer (advanced)
- Depth of invasion, mesorectal lymph node involvement
- no bowel prep or sedation
- help choose between preoperative chemoradiotherapy or straight to surgery
CT chest/Abdo/pelvis
-staging prior to treatment
Colorectal cancer management
Surgery
Obstructing colon carcinoma
-right and transverse colon (don’t usually obstruct) - resection and primary anastomosis
-left sided obstruction
—Hartman’s procedure - proximal end colostomy (+/- reversal in 6 months)
—primary anastomosis
—palliative stent
Colonic arterial supply
Middle colic artery Right colic artery Ileocolic artery Left colic artery Sigmoid artery
Resection of right colon cancer
Right hemicolectomy
Extended right hemicolectomy
Resection of left sided cancer
Anastomosis
Resection of rectal cancer
Connect rectum to anus
Pancreatic cancer epidemiology
Relatively common and highly lethal
Commonest form is pancreatic ductal adenocarcinoma
80-85% late presentation - median survival less than 6 months - 5 year survival 0.4-5%
15-20% have resectable disease - median survival 11-20 months - 5 year survival 20-25% - virtually all patients dead within 7 years of surgery
Incidence increase in western/industrialised countries
Pancreatic cancer risk factors
Chronic pancreatitis Type II DM Diet Occupation Smoking Family history
Pancreatic cancer pathogenesis
Pancreatic intraepithelial neoplasias
- PDAs evolve through non-invasive neoplastic precursor lesions
- PanINs are microscopic (<5mm diameter) and not visible to imaging a
- epigenetic alterations along the way
Pancreatic cancer presentation
Head
- at least 2/3
- jaundice -painless, palpable gallbladder
- weight loss - anorexia, malabsorption, diabetes
- pain 70% at time of diagnosis - epigastrium, radiates to back 25%
- 5% atypical attack of acute pancreatitis
- advanced - duodenal obstruction result in persistent vomiting
- GI bleeding
Body or tail
- insidious and asymptomatic
- more advanced at diagnosis
- marked weight loss with back pain in 60%
- jaundice uncommon
- vomiting sometimes at late stage
- most unresectable at diagnosis
Pancreatic cancer investigations
Tumour marker CA19-9
- falsely elevated in pancreatitis, hepatic dysfunction and obstructive jaundice
- concentrations >200 U/ml confer 90% sensitivity
- concentrations in thousands - high specificity
Dual phase CT (most)
- predict respectability in 80-90% cases
- contiguous organ invasion
- distant metastases
ERCP
- confirm double duct sign
- aspiration/brushing of bile duct system
- therapeutic modality - biliary stenting to relieve jaundice
Pancreatic cancer resections
HOP and TOP resections
Head - Whipple procedure
Tail - distal pancreatectomy
Liver cancers
Hepatocellular - cancer of liver itself
Cirrhosis hep B/C
Cholangiocarcinoma - bile duct
Gall bladder - spread quickly
Primary liver cancer
Hepatocellular carcinoma
70-90% have underlying cirrhosis, aflatoxin
Median survival without resection 4-6 months
5 year survival <5%
Systemic chemotherapy ineffective
Optimal resection surgical excision without curative intent - 5 year survival more than 30%
5-15% suitable for surgery
Gallbladder cancer
Chronic typhoid infection
Median survival without resection 5-8 months
Systemic chemotherapy ineffective
Optimal resection surgical excision with curative intent
5 year survival stage II 64%, stage III 44%, stage IV 8%
<15% suitable for surgery
Cholangiocarcinoma
Liver fluke or choledochal cyst
Median survival without resection <6 months
5 year survival <5%
Systemic chemotherapy ineffective
Optimal resection surgery excision with curative intent
5 year survival 20-40%
20-30% suitable for surgery
Secondary liver metastases
15-20% synchronous, 25% metachronous Median survival without resection <1% 5 year survival 0% Systemic chemotherapy improving Optimal resection surgical excision with curative intent 25% suitable for surgery
