GI Cancers Flashcards
What are cancers involving epithelial cells called?
Squamous Cell Carcinoma (SCC) Adenocarcinoma
What are cancers involving neuroendocrine cells called?
Neuroendocrine Tumours (NETs) Gastrointestinal Stromal Tumours (GISTs)
Give example of neuroendocrine cells of the GI tract
Enterocendocrine cells
Interstitial cells of Cajal
What are cancer involving connective tissues called?
Leiomyoma/leiomyosarcomas
Adipose tissue Liposarcomas
What are the three parts of the oesophagus?
Cervical
Middle
Lower
What are the two types of oesophageal cancer?
Squamous cell carcinoma
Adenocarcinoma
What are the main features of squamous cell carcinoma?
From normal oesophageal squamous epithelium
Upper 2/3
Acetaldehyde pathway
Less developed world
What are the main features of adenocarcinoma?
From metaplastic columnar epithelium
Lower 1/3 of oesophagus
Related to acid reflux
More developed world
What leads to adenocarcinoma?
Oesophagitis (inflammation)
Barrett’s (metaplasia)
Adenocarcinoma (neoplasia)
What is the guidelines for Barrett’s surveillance?
No dysplasia → Every 2-3 years
LGD → every 6 months
HGD → intervention
What is LGD and HGD?
Low/High Grade dysplasia
Who is most affected by oesophageal cancer?
Elderly males
What are common facts about OG cancer?
Late presentation 65% palliative High morbidity & complex surgery Poor 5-year survival <20% Palliation- difficult
What are the diagnostic methods for OG cancer?
Endoscopy and biopsy
What occurs after diagnosis?
Staging
CT Scan (chest, abdo and pelvis)
Laparoscopy (imaging with air, to look for smaller growths)
PET Scan?
What are the treatment options?
Curative:
Neo-adjuvant chemo (pre-surgery)
Radical Surgery
Palliative:
Chemo
Stent
DXT
How is a oesophagectomy performed?
Divide stomach
Divde oesophagus
Connect
OR
Two-stage Ivor Lewis approach
What are the main features for colorectal cancer?
Most common GI cancer in Western Societies
Third most common cancer death in men & women
Appendicitis is 8.6% M vs. 6.7% F
What is the lifetime risk for colorectal cancer?
Lifetime risk
1 in 10 for men
1 in 14 for women
Who is generally affected with colorectal cancer?
Generally affect patients > 50 years (>90% of cases)
What are the different forms of colorectal cancer?
Sporadic
Familial (1st degree)
Hereditary syndrome
What are the features of sporadic colorectal cancer?
Absence of family history, older population, isolated lesion
What are the features of familial colorectal cancer?
Family history, higher risk if index case is young (<50years) and the relative is close (1st degree
What are the features of hereditary 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 polyps form and become cancer?
Normal epithelium genetic mutation
hyperprolifertive small polyp
Series of other mutations
Polyp becomes cancer over few years
What are the risk factors of colorectal cancer?
Past history Colorectal cancer Adenoma, ulcerative colitis, radiotherapy Family history 1st degree relative < 55 yrs Relatives with identified genetic predisposition (e.g. FAP, HNPCC, Peutz-Jegher’s syndrome) Diet/Environmental ?carcinogenic foods Smoking Obesity Socioeconomic status
What does clinical presentation depend upon?
Location
⅔ in descending colon and rectum
½ in sigmoid colon and rectum (i.e. within reach of flexible sigmoidoscopy)
How does caecal and right-sided cancer present?
Iron deficiency anaemia (most common) Change of bowel habit (diarrhoea) Distal ileum obstruction (late) Palpable mass (late)
How does left sided & sigmoid carcinoma present?
PR bleeding, mucus Thin stool (late)
How does rectal carcinoma present?
PR bleeding, mucus
Tenesmus (urgency to defacate constantly)
Anal, perineal, sacral pain (late)
What would you do when consulting a patient with suspected colorectal cancer?
Ask them about their bowel habits?
Examine abdomen for any palpable masses
How would local invasion in the pelvis present?
Bladder symtoms
Female genital tract symptoms
How might metastatic colorectal cancer present?
Liver (hepatic pain, jaundice) Lung (cough) Regional lymph nodes Peritoneum Sister Mary Joseph nodule (growth in umbilicus) Hepatomegaly (mets) Monophonic wheeze Bone pain
What are the signs of primary colorectal cancer?
Abdominal mass
DRE: most <12cm dentate and reached by examining finger
Rigid sigmoidoscopy
Abdominal tenderness and distension – large bowel obstruction
What investigations could you do when diagnosing colorectal cancer?
Historically, barium enema
Colonoscopy now
Describe colonoscopy
Can visualize lesions < 5mm
Small polyps can be removed
Reduced cancer incidence
Usually performed under sedation
Describe CT colonoscopy
Can visualize lesions > 5mm No need for sedation Less invasive, better tolerated If lesions identified patient needs colonoscopy for diagnosis Very detailed
What dictates which parts of the colon can be removeD?
Blood supply
Describe the epidemiology of pancreatic cancer
Commonest form of panc CA is pancreatic ductal adenocarcinoma (PDA)
80-85% have late presentation
15-20% have resectable disease
Incidence & mortality roughly equivalent
Why is pancreatic cancer so difficult to diagnose?
No unique diagnostic features
What are risk factors for pancreatic cancer?
Chronic pancreatitis
Type II diabetes mellitus
Cigarette smoking
Family history
What syndrome results in a high risk of PDA?
Hereditary pancreatitis 40% chance Genes: PRSS1 SPINK1 CFTR
Describe the pathogenesis of pancreatic cancer
PDAs evolve through non-invasive neoplastic precursor lesions
PanINs are microscopic (<5 mm diameter) & not visible by pancreatic imaging
Acquire clonally selected genetic & epigenetic alterations along the way
How does pancreatic cancer present clinically (head)?
Jaundice (compression of CBD) Weight loss Pain (epigastrium radiated to back) Acute pancreatitis (unusual) Gastrointestinal bleeding (unusual)
How does carcinoma of the body of tail and pancreas present?
Asymptomatic in early stages Weight loss Back pain Vomiting in late stages Most are unresectable at the time of diagnosis
What are the diagnostic methods for pancreatic cancer?
Tumor marker CA19-9
Ultrasonography
Dual-phase CT
MRI/MRCP/ERCP/EUS
PET
How do you treat pancreatic cancer surgically?
HOP resection
Join stomach to pancreas and bile duct
If in tail: remove affected area
What is HCC
Hepatocellular carcinome
What are risk factors for HCC?
Cirrhosis
Hep B
What is the best way to treat HCC?
Liver transplant
What is ChCA?
Cholangiocarcinoma
poor prognosis
<5% at 5 years
What causes ChCA?
PSC and UC
Liver fluke
Choledochal cyst
What causes gallbladder cancer?
GS
porcelain GB
Chronic typhoid infection
