Colorectal Cancer - Clinical Flashcards
risk factors for colorectal cancer
>65 years old low intake of fibre high intake of fat, sugar, alcohol, red meat, processed meats obesity smoking lack of exercise
most common site effected by colorectal cancer
left side - 50%
right side - 25%
4-5% are synchronous lesions
how do majority of colorectal cancers arise
from pre-existing adenomatous polyps (between 3-5/10 years)
aetiology of colorectal cancer
sporadic
predisposing conditions
sporadic causes of colorectal cancer
mutations in APC (100% risk of cancer)
mutations in p53
predisposing conditions causing colorectal cancer
chronic IBD;
ULC>Crohn’s
how can colorectal cancer spread
direct
lymphatic
blood borne - liver, lung
transcoelomic (rare)
presentation of colorectal cancer
bowel screening programme
urgent presentation of colorectal cancer
via SOPD or endoscopy;
presents with red flags symptoms
emergency presentation of colorectal cancer
obstruction
rectal bleeding
palpable mass
perforation
signs of right sided colorectal cancer
unexplained iron deficiency anaemia persistent tiredness persistent and unexplained change in bowel habit unexplained weight loss abdominal pain - colicky lump in abdomen
signs left sided colorectal cancer
rectal bleeding
feeling of incomplete emptyign
worsening constipation
red flags of colorectal cancer
recent change in bowel habit bleeding from back passage recent weight loss abdominal pain swelling in abdomen family hx previous operations
tests for colorectal cancer
sigmoidoscopy v colonoscopy
CT colonography
MRI - rectal cancers
describe features of polyp cancer
sessile
pedunculated (has a stalk)
