Colorectal Cancer Flashcards
Types of colorectal polyps
Inflammatory, hamartomatous (benign, focal malformation that resembles a neoplasm in tissue of origin), metaplastic, neoplastic
Genes associated with cancer
Oncogenes - Promote normal growth and division, cause excess cell growth and division when mutated
Tumour suppressor genes - Suppress cell growth and division, allow cell growth and division when mutated
Staging of cancer
TNM or Dukes
Explain Dukes staging system
Dukes A - Mucosa B1 - Into muscularis propria B2 - Through muscularis propria C1 - Tumour spread to <4 lymph nodes C2 - Tumour spread to > 4 lymph nodes D - Distant metastases
Example of autosomal dominant inheritance of colorectal cancer
Familial adenomatous polyposis -
Mutation in APC gene
Hereditary nonpolyposis colorectal cancer -
Mutation in DNA mismatch repair gene
Symptoms of colorectal cancer in caecum
Anaemia
Symptoms of colorectal cancer in descending colon
Pain, change in bowel habit, rectal bleeding
Symptoms of colorectal cancer in rectum
Rectal bleeding, tenesmus
Clinical findings on examination
Anaemia, cachexia, lymphadenpathy
Hepatomegaly, distensions
Rectal bleeding, mass
6 weeks on unexplained change in bowel movement
Iron deficiency anaemia
Iron-deficiency tablet but carry out OGD and endoscopy, possible caecal cancer
Sigmoidoscopy vs colonoscopy
Sigmoidoscopy - If rectal bleed is bright red
Colonoscopy - If iron deficiency anaemia, to see where problem is
Why do we prefer endoscopy > CT colography
Endoscopy has diagnostic and therapeutic use
Toblerone sign on endoscopy
Endoscope is in transverse colon
What can be used to check for blood hidden/not seen in stool
Faecal Occult Blood Test (FOBT)
What is the Scottish Bowel Screening Programme
50-75-year-olds invited every 2 years for a bowel scan