Gastrointestinal Cancers Flashcards
What is the definition of cancer?
a disease characterised by the uncontrolled division of abnormal cells in the body
What type of cancer tends to arise from squamous epithelial cells?
squamous cell carcinoma
What type of cancer tends to arise from metaplastic columnar epithelial cells?
adenocarcinoma
What type of cancer tends to arise from enteroendocrine cells?
neuroendocrine tumours (NETs)
What type of cancer tends to arise from interstitial cells of Cajal cells?
Gastrointestinal Stromal Tumours (GISTs)
What type of cancer tends to arise from smooth muscle cells?
Leiomyoma/leiomyosarcomas
What type of cancer tends to arise from adipose tissue cells?
Liposarcomas
What musculature makes up the oesophagus?
upper 2/3 = skeletal
lower 1/3 = smooth
Where does the oesophagus start?
C5
Where does the oesophagus end?
T10
Where do you tend to find squamous cell carcinoma?
upper 2/3 of the oesophagus
What pathway is associated with squamous cell carcinoma?
acetyldehyde patheay
EtOH to acetate
What is oesophagitis?
inflammation of the oesophagus (caused by GORD)
How prevalent is oesophagitis?
30% of the UK population
What is Barretts oesophgus?
metaplasia of the oesophagus
How prevalent is Barretts oesophgus?
5% of the GORD population
What is the risk of cancer with Barret’s oesophagus?
0.5-1%/year
30-100 fold risk of cancer
How do oesophageal cancers present?
- late
- dysphagia
- weight loss
Where do you tend to find adenocarcinomas in the oesophagus?
lower 1/3 of the oesophagus
What tends to cause adenocarcinomas in the oesophagus?
acid reflux
What are the Barrett’s surveillance guidelines when no dysplasia is seen?
every 2-3 years (endoscopy)
What are the Barrett’s surveillance guidelines when low grade dysplasia is seen?
every 6 months
What are the Barrett’s surveillance guidelines when high grade dysplasia is seen?
intervention (cancer is highly likely)
What population does squamous adenocarcinoma of the oesophagus most affect?
- elderly patients
- males more than females
How do you diagnose oesophageal cancer?
endoscopy and biopsy
How do you stage oesophageal cancer?
- CT scan
- Laparoscopy
- ?Endoscopic US
- ?PET scan
Why to do you do a laparoscopy?
to ensure there aren’t any metastases
How do you treat squamous cell cancer?
- radiotherapy
How do you treat adenocarcinomas?
- neo-adjuvant chemotherapy
- followed by surgery
What happens to the palliative instances of oesophageal cancer?
- chemotherapy
- DXT
- stent
What happens in a oesophagectomy?
Two-stage Ivor Lewis approach
removing parts of the stomach and the oesophagus
What population is most affected by colorectal cancer?
- > 50 years old
- men
What are the different forms of colorectal cancer?
- sporadic
- familial
- hereditary syndrome
What is the sporadic form of colorectal cancer?
- Absence of family history
- Older population
- Isolated lesion
What is the familial form of colorectal cancer?
Family history, higher risk if:
- index case is young (<50years)
- the relative is close (1st degree)
What is the hereditary syndrome form of colorectal cancer?
- Family history
- Younger age of onset
- Specific gene defects
e. g. - Familial adenomatous polyposis (FAP)
- Hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome)
How do people with Familial adenomatous polyposis?
- young polyps
- removals of lots of the large colon at a young age
What can cause hyperproliferative epithelium?
APC mutation
What can cause a small adenoma?
COX-2 overexpression
What can cause a small adenoma to develop into a large adenoma?
K-ras mutation
What can cause a large adenoma to develop into a colon carcinoma?
- p53 mutation
- loss of 18q
What is thought to prevent the progression of polyps to colorectal cancers?
aspirin
What are the risk factors of developing Colorectal cancers?
PMHx - colorectal cancers - adenoma, UC, and radiotherpy FHx - first degree relative - genetic predisposition Lifestyle - smoking - obesity - socioeconomic status
Where does colorectal cancer occur?
2/3 - descending colon, rectum
1/2 - sigmoid colon and rectum (seen on sigmoidoscopy)
How does caecal and right sided cancer present?
- iron deficiency anaemia
- bowel habit changes (diarrhoea)
- distal ileum obstruction (late)
- palpable mass (late)
How does sigmoid and left sided cancer present?
- PR bleeding
- mucus
- thin stools (late)
How does rectal cancer present?
- PR bleeding
- mucus
- tenesmus
- anal, perineal and sacral pain
- bowel obstruction (late)
What are the late signs of local invasion of a carcinoma?
- bladder symptoms
- female genital tract symptoms
What are the late signs of metastasis of a carcinoma?
- liver: hepatic pain, jaundice
- lung: cough
- regional lymph nodes
- peritonism: sister mary joseph nodule
What are the signs of primary colorectal cancer?
- abdominal mass
- DRE: most <12cm from dentate line and reached by finger
- rigid sigmoidoscopy
- abdominal tenderness and distension (large bowel obstruction)
What are the signs of metastasis and complications of colorectal cancer?
- hepatomegaly
- monophonic wheeze
- bone pain
How do you diagnose colorectal cancer?
- FIT (faecal immunochemical test) for occult blood
- FBC: anaemia, haematinitcs, low ferritin
- tumour markers: CEA (NOT a diagnostic tool)
How do you investigate colorectal cancer?
- colonscopy
- CT colonoscopy/colonography
- MRI pelvis
Why is a colonscopy used to investigate colorectal cancer?
- can visualize lesions <5mm
- small polyps can be removed
- reduced cancer incidence
- performed under sedation
Why is a CT colonoscopy/colonography used to investigate colorectal cancer?
- can visualize lesions >5mm
- no need for sedation
- less invasive, better tolerated
- colonoscopy is still needed for diagnosis if lesions are identified
Why is a MRI pelvis used to investigate colorectal cancer?
- depth of invasion
- mesorectal lymph node involvement
- no bowel prep or sedation required
- help choose between preop chemoradiotherapy or straight to surgery
What scans are used to stage a colorectal cancer prior to treatment?
CT chest/abdomin/pelvis
How do you manage an obstructing colon carcinoma in the right and transverse colon?
- resection
- primary anastomosis
How do you manage an obstructing colon carcinoma in the left sided colon?
Hartmann's procedure - proximal end colostomy (LIF) - reversal in 6 months Primary anastomosis - intraoperative bowel lavage with primary anastomosis (10% leak) - defunctioning ileostomy Palliative stent
What arteries supply the right and transverse colon?
- Iliocolic
- Right colic
- Middle colic
What arteries supply the left sided colon?
- Left colic
- sigmoid arteries
What happens in a Right Hemicolectomy?
- right side of the large bowel
- removing the ascending colon, caecum
- connecting the terminal ileum, to the transverse colon
What happens in a Extended Right Hemicolectomy?
- remove 2/3 or the large bowel (caecum, ascending colon and part of the transverse colon)
- connect terminal ilium to the remainder of the transverse colon
What happens in a Left Hemicolectomy?
- remove the descending colon
- connect transverse colon to the sigmoid colon via anastomosis
How do you resect with rectal cancer?
- remove the rectum and part of the sigmoid colon
- connect the remaining colon (sigmoid) to the anus
What is normally done instead of a resection with rectal cancer?
iliostomy
What is the most common cause of pancreatic cancer?
pancreatic ductal adenocarcimona
When does pancreatic cancer tend to present?
- late (80-85%)
only 15-20% have resectable disease
When does pancreatic cancer tend to occur?
between 60-80 years of age
What are the risk factors of pancreatic cancer?
- chronic pancreatitis (18 fold risk)
- T2DM
- cholelithiasis
- previous gastric surgery
- pernicious anaemia
- diet (high in fat, protein, coffee and etOH)
- occupation (chemical and metal exposure)
- smoking
- family history (hereditary pancreatitis
What are pancreatic intraepithelial neoplasias?
- microscopic (<5mm)
- not visible by pancreatic imaging
What happens in the development of pancreatic ductal adenocarcinomas?
- non-invasive neoplastic precursor lesions
- that acquire clonally selected genetic and epigenetic alterations along the way
What mutations are associated with PanIN-1?
K-Ras mutations
What mutations are associated with PanIN-2?
CDKN2A
What mutations are associated with PanIN-3?
BRCA2, TP53
How does a carcinoma at the head of the pancreas present?
(2/3)
- Jaundice
- Weight loss
- Pain
- acute pancreatitis
- GI bleeding
- vomiting
What causes jaundice with a carcinoma at the head of the pancreas?
- invasion or compression of the CBD
- painless
- Courvoisier’s sign (palpable gallbladder)
What causes weight loss with a carcinoma at the head of the pancreas?
- anorexia
- malabsorption (due to exocrine insufficiency)
- diabetes
What causes pain with a carcinoma at the head of the pancreas?
70%
- epigastrium
- radiates to the back (25%)
What does pain with a carcinoma at the head of the pancreas indicate?
- posterior capsule invasion
- irresectability
What does vomiting with a carcinoma at the head of the pancreas indicate?
duodenal obstruction
What does GI bleeding with a carcinoma at the head of the pancreas indicate?
- duodenal invasion
- varices (due to portal or splenic wein occlusions)
How does a carcinoma at the body and tail of the pancreas present?
- asymptomatic at the early stages
- weight loss
- back pain
- vomiting
- unresectable at time of diagnosis
- jaundice unlikely
What does vomiting with a carcinoma at the body and tail of the pancreas indicate?
(late) - invasion of the DJ flexure
What investigations can be done with pancreatic cancer?
- Tumour marker: CA19-9
- Ultrasonography
- Dual-phase CT
- MRI
- MRCP
- ERCP
- EUS
- laparoscopy and laparascopic US
- PET
What does the Tumour marker: CA19-9 indicate?
- falsely elevated in: pancreatitis, hepatic dysfunction and obstructive jaundice
- conc. >200U/ml = 90% sensitivity
- conc. > 1000 = high sensitivity
What can an ultrasonography detect?
- identify pancreatic tumours
- dilated bile ducts
- liver metastases
What can a dual-phase CT detect?
- accurately predict resectability in 80-90% of cases
- contiguous organ invasion
- vascular invasion (coeliac axis and SMA)
- distant metastases
What can an MRI detect?
detects and predicts resectability with accuracies similar to a CT
What can an MRCP detect?
provides ductal images without ERCP complications
What can an ERCP detect?
- confirms the typical double duct sign
- aspiration/brushing of the bile-duct system
0 therapeutic modality - biliary stenting to relieve jaundice
What can an EUS detect?
- highly sensitive in the detection of small tumours
- assesses vascular invasion
- FNA
What can a laparoscopy and laparoscopic US detect?
radiologically occult metastatic lesions of liver and peritoneal cavity
What can a PET detect?
demonstrates occult metastases
When do you do a whipple resection?
when the carcinoma is at the head of the pancreas
What is a whipple resection?
- remove: distal bile duct, gall bladder, distal stomach, all of the duodenum until the jejunum starts
- bile duct, stomach and remaining pancreas attach to the small intestine
What is a TOP resection?
- remove: distal part of pancreas (tail and body), spleen)
What are the 4 different types of liver cancer?
- Hepatocellular cancer
- Cholangiocarcinoma
- Gall Bladder cancers
- Colorectal cancer liver metastases
Where does hepatocellular cancer occur?
in the hepatocytes of the liver itself
When does hepatocellular cancer tend to occur?
- when patients have cirrhosis
- HEP B/C and alcohol disease
Where does Cholangiocarcinoma occur?
- bile ducts, the bifurcation of the common hepatic duct
How do you treat hepatocellular cancer?
(chemo is ineffective) Optimal is surgical excision with curative intent - liver transplant - transarterial haemoembolisation - radiofrequency ablation
What is associated with gallbladder cancer?
- gallstones
- porcelain gall bladder
- chronic typhoid infections
How do you treat gallbladder cancer?
(chemo is ineffective)
surgical excision with curative intent
What is the 5 year survival rate of cancer?
stage 2: 64%
stage 3: 44%
stage 4: 8%
What does stage 2 gallbladder cancer mean?
- transmural invasion
- excision is effective
What does stage 3 gallbladder cancer mean?
- invades the liver
- surgical excision if qualify
What does stage 4 gallbladder cancer mean?
- invaded the liver >2cm
- distal metastases
- unlikely to qualify for surgery
What is thought to cause Cholangiocarcinoma?
- choledochal cyst
- UC and primary scloerosing cholangitis
- liver flukes
How do you treat Cholangiocarcinoma?
surgical excision with curative intent
- in the liver, at the hilum, distally
How do you treat secondary liver metastases?
(chemo improving)
surgical excision with curative intent
How do you surgically resect a hepatocellular cancer?
remove the affected part of the liver (as little as possible)
How do you surgically resect a gallbladder cancer?
remove the gallbladder, all the lymphnodes, liver tissue surrounding
How do you surgically resect a Cholangiocarcinoma?
remove the half of the liver with the tumour
What are the different types of causes of dysphagia?
- abdominal
- cardiac
- other
What are the structural abdominal causes of upper dysphagia?
- Pharyngeal cancer
- Pharyngeal pouch
What are the neurological abdominal causes of upper dysphagia?
- Parkinson’s
- Stroke
- Motor neurone disease
What are the structural abdominal causes of lower dysphagia?
inside(mural and luminal): - oesophageal or gastric cancer - stricture - Schatzki ring outside (extrinsic compression): - lung cancer
What are the neurological abdominal causes of lower dysphagia?
- Achalasia
- diffuse oesophageal spasm
What are the cardiac causes of lower dysphagia?
post-prandial angina
What are the other possible causes of lower dysphagia?
- globus sensation
- anxiety
How could you differentiate between dysphagia and angina?
- pain seconds after swallowing is unlikely to be angina
- unusual to happen only after meals ?exertional
Why can angina occur after meals?
- blood shifts to the bowel for digestion
- blood supply limited through narrowed coronaries
How can you differentiate between upper and lower dysphagia?
upper: food is painful on swallowing
lower: food is easy to swallow but feels stuck seconds later
How can you differentiate between neurological and mechanical cause of dysphagia?
if both solids and liquids are difficult to swallow - it is likely neruological
What would put a patient at risk of strictures?
Hx of reflux
What investigations would be done for a suspected oesophageal cancer?
- ECG (rule out cardiac causes)
- FBC (anaemia)
- U+Es (dehydration)
- CXR
- upper GI endoscopy
What is associated with dysphagia?
aspiration pneumonia
What is needed when considering treatment of lower oesophageal adenocarcinoma?
- Staging CTCAP (look at invasion and metastases)
- PET scan (anything missed by CT)
- Staging laparoscopy (last line, very small metastases)f
What causes microcytic anaemia?
- Iron deficiency anaemia
- Anaemia of chronic disease
- Thalassaemia
- Sideroblastic anaemia
What is classified as microcytic anaemia?
MCV<80
What causes normocytic anaemia?
- Aplastic anaemia
- Bleeding
- Chronic disease
- Destruction (haemolysis)
- Endocrine disorders:
Hypothyroidism
Hypoadrenalism
What is classified as normocytic anaemia?
MCV 80-96
What causes macrocytic anaemia?
- Foetus (pregnancy)
- Alcohol excess
- Thyroid disorders
- Reticulocytosis
- B12/Folate deficiency
- Cirrhosis
What is classified as macrocytic anaemia?
MCV>96
What causes iron deficiency anaemia?
blood loss
- increased demand
- decreased absorption
What are the common gastric causes of iron deficiency anaemia?
- Aspirin/NSAID use
- Colonic adenocarcinoma
- Gastric carcinoma
- Benign gastric ulcer
- Angiodysplasia
- Coeliac disease
- Gastrectomy (decreased absorption)
- H.pylori
What are the common non-GI causes of iron deficiency anaemia?
- Menstruation
- Blood donation
- Haematuria (1% of iron deficiency anaemias)
- Epistaxis
Any overt bleeding noticed - to explain iron deficiency anaemia?
Blood in stool
Haematuria
Epistaxis
Haemoptysis
Generic symptoms of malignancy?
- Weight loss
- Anorexia
- Malaise
What symptoms that might suggest colorectal cancer?
- Change in bowel habit
- Blood or mucus in stool
- Faecal incontinence
- Tenesmus
Symptoms that might suggest an upper GI cancer?
- Dysphagia
- Dyspepsia
What does Malena indicate?
upper GI bleeding
What does bright red PR bleeding indicate?
- lower GI
- haemorrhoids
What does blood and stool mixed indicated?
large colon issues
What tests would you do if colorectal cancer is suspected?
- Urine dipstick (haematuria?)
- Iron studies (confirm iron deficiency as the cause of microcytic anaemia)
- anti-TTG (coeliac screening)
- urgent colonoscopy through the 2-week-wait suspected cancer pathway. - - If negative, an upper GI endoscopy will be organised
What qualifies you for the 2-week wait suspected cancer colonoscopy?
blood in the stool
What tests need to be done to decide on a treatment plan for a descending colon adenocarcinoma?
- Staging CTCAP
(metastases picked up easily) - MRI liver, pelvis
How do you manage a descending colon adenocarcinoma T3N0M1?
- resect primary colonic tumour/colonic stent
- neoadjuvant chemotherapy
- liver resection
