What cause of cancer death is colorectal cancer?
What overall cause of cancer is colorectal cancer?
What is the most common histological classification of colorectal cancer?
What percentage of colorectal cancer is colonic and what is rectal?
2/3 is colonic
1/3 is rectal
What genes are associated with colorectal cancer?
Other CRP syndromes
What are risk factors for sporadic cases of colorectal cancer?
Environmental influences (diet, obesity, lack of exercise, smoking, diabetes)
What kind of things in your diet are risk factors for colorectal cancer?
Low fruit and veg
High red meat
What percentage of colorectal cancers have no genetic influence?
What do majority of colorectal cancers arise from?
What are polyps?
What are the different kinds of polyps?
Epithelial or mesenchymal
Benign or malignant
What is an adenoma?
Benign tumour of glandular tissue
What is an adenoma in origin?
What are the different histological types of adenoma?
Indeterminate tubulovillous (15%)
Explain the adenoma-carcinoma sequence?
Activation of oncogene, loss of tumour suppresor gene and defective DNA repair pathway genes (microsatelite instability) cause adenoma to become carcinoma by causing cell growth proliferation apoptosis
What are examples of oncogenes?
What is an oncogene?
A gene that has the potential to cause cancer
What are examples of tumour suppressor genes?
What are tumour suppresor genes?
Ones that control cell growth
What is the presentation of colorectal cancer?
Rectal bleeding (especially if mixed in with stool)
Altered bowel opening to loose stools (longer than 4 weeks)
Palpable rectal or right lower abdominal mass
Acute chronic obstruction if stenosing tumour
What investigations are done for colorectal cancer?
What is the investigation of choice for colorectal cancer?
What can be done with a colonoscopy?
What does a colonoscopy require?
What are risks of a colonoscopy?
What radiological imaging is done for colorectal cancer?
What investigations are done to stage colorectal cancer?
CT scan of chest/abdomen/pelvis
MRI scan for rectal tumours
PET scan/rectal endoscopic ultrasound in selected cases
For Duke's staging, what is T1 to T4?
T1 - confined to submucosa
T2 - confined to muscularis
T3 - confined to serosa
T4 - breached serosa, invading other structures
For Duke's staging, what is N0 to N2?
N0 - no lymph node involvement
N1 - seen in 3 regional lymph nodes
N2 - seen in 4+ regional lymph nodes
For Duke's staging, what is M0 to M1?
M0 - no metastases to distinct organs
M1 - metastasis to distinct organs