Colorectal Polpys/Cancer Flashcards
What type of cancer is colorectal cancer?
Adenocarcinoma
what is the precursor for the cancer?
Adenoma (or polyp)
How does a colorectal polyp form?
Mostly spontaneous & benign, common with age but can progress to cancers
What is a Colorectal polyp?
An overgrowth of epithelial cells of colon or rectum - benign but can become malignant
Which 2 conditions massively increase risk of polyps/cancer?
What kind of gene is it that causes these?
Familial adenomatous Polyposis (FAP)
Hereditary Non polyposis colon cancer (HNPCC - Lynch Syndrome)
Auto Dom
What is familial adenomatous Polyposis (FAP)?
What kind of mutation?
How does it form a cancer?
Auto dom APC gene mutation, 1000s of duodenal polyps
Inevitably get colorectal cancer (93% risk by 50)
What is Hereditary non polyposis colon cancer (HNPCC) ?
What kind of mutation?
How does it form a cancer?
Auto dom MSH-1 mutation (or MSH-2) - a DNA mismatch repair gene
Rapidly increases progression, Adenoma –> Adenocarcinoma
RF for colorectal cancer
Familial inherited genetic predisposition
Adenomas/polyps
Alcohol, smoking, UC
Where are common metastasis of this cancer found?
Liver and lung
Symptoms of Colorectal cancer
Mostly in distal colon (sigmoid onwards) therefore:
LLQ pain
Bloody mucusy stools (fresh blood, distal colon closer to anus)
Tenesmus (feel the need to pass stool if bowels empty) - if rectal involvement
Fe def anemia (due to bleeding)
How to diagnose it?
FIT (fecal occult) - screening test for microblood particles in poop
Suspected cancer pathway referral = 2 week wait
(Px with positive FIT & suspected colorectal cancer referred for colonoscopy / biopsy within 2 weeks)
GS = Colonoscopy / biopsy
Who is the FIT test done to?
all 60+ with Fe def anemia + bowel habit change
What classification is used?
TNM
Treatment?
Surgery (+ chemo) only curative option, if no mets
