Colorectal cancer Flashcards
Aetiology of colorectal cancer
genetic syndromes
diet - high in fat and cholesterol, processed and red meat
obesity
alcohol
diabetes
smokers
Describe familial adenomatous polyposis (FAP)
autosomal dominant inheritance
(30% new mutations)
hundreds of adenomatous polyps
risk of developing CRC >90% by age 70 without surgery
Familial adenomatous polyposis treatment
prophylactic surgery 16-25 depending on polyp count/size/dysplasia
Extracolonic manifestations of familial adenomatous polyposis
desmoid tumours
duodenal adenomas
skin lesions - epidermoid cysts
osteomas in mandible + maxilla
CHRPE - congenital hypertrophy retinal pigment epithelium
Lynch syndrome other name
hereditary non-polyposis colorectal cancer (HNPCC)
Describe Lynch syndrome
autosomal dominant
3 or more relatives with colorectal cancer in 2 generations
lifetime risk 85%
more right sided colonic lesions
endometrial/TCC of bladder/gastric/ovarian/pancreatic/biliary/haematological malignancy
colonoscopy screening every 2 years
Describe the NHS bowel cancer screening programme
faecal immunochemical test (FIT) and colonoscopy screening every 2 years to all men and women 60-75
flexible sigmoidoscopy screening once at 55y
Clinical features of colorectal cancer
change in bowel habit
rectal bleeding
anaemia
abdominal pain
mucus/tenesmus
abdominal mass
weight loss
emergency - obstruction, peritonitis, bleeding
When is colonic stenting used?
initially in patients with metastatic disease
in large bowel obstruction to get patient fit and plan elective surgery
sometimes in benign strictures
Surgery complications of colorectal cancer
anastomotic leak
wound infection
DVT/PE
bleeding
nerve injury
cardiopulmonary
stoma complications
How to exclude anastomotic leak after bowel surgery if suspicious
CT with contrast
