Colorectal Cancer

Question 1

What are predisposing factors to colorectal carcinoma?

Answer 1

• Family history
• IBD - Crohns or Collitis
• Diet & lifestyle
• DM

Question 2

What are protective factors against colorectal carcinoma?

Answer 2

• Aspirin (NSAID’s)!

Question 3

Outline the presentation of colorectal cancer

Answer 3

Left sided;

• Bleeding/ mucus PR
• Altered bowel habit/ obstruction
• Tenesmus (desire to empty bowel)
• Mass in LIF

Right;

• Weight loss
• Anaemia (iron defeiciency)
• Bleeding
• Mass in RIF

Either;

• Perforation
• Haemorrhage
• Fistula

Question 4

What investigations would you perform for suspected colorectal cancer?

Answer 4

• Sigmoidoscopy
• Colonoscopy - gold
  
  • Or barium enema if CI
• CT/ MRI & USS Liver
• Carcino-embryonic antigen (CEA) (raised in GI neoplasms)
  
  • monitoring - high is bad
• FOB & PR exam

Question 5

Outline the pathological staging systems for colorectal cancer

Answer 5

Dukes

• A - Beneath muscularis mucosa
• B - muscularis mucosa
• C - Lymph nodes
• D - Metastases

(5 year survival rates, A~90%, B~65%, C~30 & D<10%)

TNM

• Tumor 0-4 - stages of invasion
• Nodes 0-2 - 0 or 1-3 or 4< nodes involved
• Metastasis 0-1 - metastases present or not

Question 6

Outline the surgical treatments for colorectal cancer

Answer 6

SURGERY

• Right hemicolectomy - start of colon
• Left hemicolectomy - end of colon
• Sigmoid colectomy - sigmoid
• Anterior resection - rectal
• Abdomino-perineal (AP) resection - tumours low in the rectum (<8cm from anus) [permanent colostomy & removal of rectum & anus)
• Hartmann’s procedure - emergency bowel obstruction or palliation
• Transanal endoscopic microsurgery - local excision in those unfit for surgery
• Laparascopic surgery - safe alternative to open
• Endoscopic stenting - palliative or bridge to surgery in acute obstruction (reduces alot of complications..)

Question 7

Outline non-surgical treatments of colorectal cancer

Answer 7

Radiotherapy

• Pre-op (neoadjuvant) in rectal cancer to reduce local recurrence and inc 5yr survival
  
  • Often used +/- 5-FU chemotherapy to downstage initially unresectable rectal tumours
• Post-op (adjuvant) used with high recurrence risk rectal tumours
• Inc post-op complications (DNT, pathological fractures, fistulization)

Chemotherapy

• Adjuvant (post-op) 5-FU +/- other agents (eg folinic acid, levamisole) reduce Dukes’ C mortality ~25%
• Paliation in metastatic disease

Question 8

Define what polyps are, their different types and symptoms they can cause

Answer 8

Polyps are lumps that appear above the mucosa;

• Inflammatory
  
  • UC/ Crohn’s
  • Lymphoid hyperplasia
• Hamartomatous (due to faulty growth of organ, looks like neoplasm)
  
  • Juvenile polyps
  • Peutz-Jeghers syndrome
• Neoplastic (malignant potential)
  
  • Tubular or villous adenomas

Symptoms;

• Blood/ mucus PR

Question 9

Outline the NHS Bowel Cancer Screening Programme

Answer 9

Screening offered every 2 years to all men and women ages 60-69 using FOB testing.

Abnormal results are offered an appointment.

Question 10

Outline the different types of stomas and their functions

Answer 10

• Gastrostomy
  
  • Percutaneous tube located in epigastrium into stomach
  • Feeding or gastric decompression
• Jejunostomy
  
  • Percutaneously into jejunum to allow enteral feeding (eg following oesophagectomy)
• Ileostomy
  
  • Terminal ileum brought to skin in the right iliac fossa
  • End: ilium discontinuated, spout shaped in RIF
  • Loop: ilium is continuity, temporary means
• Colostomy
  
  • Any part of colon
  • Usually LIF, flush with skin
  • Loop used for decompression, End following major bowel resection
• Mucous fitula
  
  • Distal end of transected colon brought to skin for decompression
  • Proximal end also brought out at ileostomy or colostomy
  • Usually LIF and flush with skin
• Double barrel stoma
  
  • An end stoma and mucous fistula that have been sited side by side
  • Allows easy reversal