Colorectal Ca

• Colorectal cancer is the 4th most prevalent cancer in the UK
• Red flags for colorectal cancer:

  • Change in bowel habit
  • Unexplained weight loss
  • PR bleeding
  • Unexplained abdominal pain
  • Iron deficiency anaemia
  • Abdominal or rectal mass on palpation
• NICE 2WW criteria for lower GI cancer:

  · Over 40 years old with abdominal pain and unexplained weight loss

  · Over 50 years old with unexplained rectal bleeding

  · Over 60 years with a change in bowel habit or Iron deficiency anaemia
• Faecal immunochemical tests (FIT) look very specifically for the amount of human haemoglobin in the stool. Can be used in general practice to help assess for bowel cancer in specific patients who do not meet the 2WW criteria.

  NICE now ask for FIT prior to referral (unless mass found)
• FIT tests are used for bowel cancer screening programme in England. People aged 60-74 are sent a home FIT test every 2 years. If the result is positive, the patient will be sent for colonoscopy.
• There are a number of factors that increase the risk of colorectal cancer:

  • Family history of bowel cancer
  • Familial adenomatous polyposis (FAP)
  • Hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome
  • Inflammatory bowel disease
  • Increased age
  • Diet high in red and processed meat, and low in fibre
  • Obesity and sedentary lifestyle
  • Smoking
  • Alcohol
• Adenocarcinoma is the most common type of colorectal cancer
• Most colorectal cancers arise from pre-cancerous polyps
• It is important to examine patients with colorectal cancer red flag symptoms for Lymphadenopathy - most importantly the left supraclavicular lymph node - virchows node
• A FBC in patients with colorectal cancer normally shows a microscopic anaemia
• • CT chest, abdomen and pelvis: patients with suspected colorectal cancer at colonoscopy or CT colonography will require completion CT to look for staging
• The liver is the most common site of spread
• Carcinoembryonic antigen (CEA): A serum marker indicative of colorectal cancer. It is not used to screen for colorectal cancer but may be measured at time of diagnosis and used to monitor as a marker of recurrence.
• Colonoscopy is the gold-standard investigation. It allows visualisation of the colon, identification of malignant lesions and pre-malignant or suspicious polyps.
• Most colorectal cancers develop via progression of normal mucosa to colonic adenoma (polyps) to invasive adenocarcinoma

  Progression to adenocarcinoma occurs in around 10% of adenomas (polyps)
• The common clinical features of bowel cancer include change in bowel habit, rectal bleeding, weight loss, abdominal pain, and symptoms of (iron-deficiency) anaemia.

  • Right-sided colon cancers – abdominal pain, iron-deficiency anaemia, palpable mass in right iliac fossa, often present late
  • Left-sided colon cancers – rectal bleeding, change in bowel habit, tenesmus, palpable mass in left iliac fossa or on PR exam
• Management:

  • MDT
  • Only definitive curative option is surgery - often alongside chemotherapy or radiotherapy
  • The general plan for most surgery is regional colectomy followed by either primary anastomosis or formation of a stoma e.g. right hemicolectomy for caecal tumours
  • Hartmann's procedure when emergency bowel surgery needed e.g. obstruction of perforation secondary to malignant mass