Colorectal

Question 1

What are the risk factors for colorectal Ca?

Answer 1

Western diet - low fibre

FAP - Familial Adenomatous Polyposis

Lynch syndrome - non-polyposis colorectal cancer (HNPCC)

Smoking

UC

Question 2

What is the histology of colorectal Ca?

Answer 2

Adenocarcinoma

Question 3

How should colorectal Ca be investigated?

Answer 3

CEA - (carcinoembryonic antigen)

Staging CT TAP - liver mets

Colonoscopy + biopsy

Barium enema

Question 4

How is colorectal Ca staged?

Answer 4

Modified Dukes Classification

A = not in muscularis propria

B = beyond muscularis propria

C1 = LN +ve (apical node spared)

C2 = LN +ve (apical node involved)

Question 5

How should colorectal Ca be surgically managed?

Answer 5

Surgery = curative, +/i neoadjuvant/adjuvant, RT in rectal Ca

• Caecal Ca = R hemicolectomy
• Transverse colon Ca = extended R hemicolectomy
• L colon Ca = L hemicolectomy
• Sigmoid Ca = sigmoid colectomy
• Rectal Ca = anterior resection of the rectum, Total mesorectal excision
• Low rectal Ca = abdomino-perineal excision of rectum (APER)
• Palliative = stent, bypass, defunctioning stoma, palliative resection

Question 6

How is colorectal Ca screened for?

Answer 6

55 = one-off bowel scope screening test

60-74 = every 2yrs with fecal occult blood testing (FOB) home testing kit

>75 = can ask for a home testing kit every 2yrs by calling the bowel Ca screening helpline

Question 7

How does colon cancer present?

Answer 7

Right colon

•Weight loss, weakness, rarely obstruction, iron def anaemia

Left colon

•Constipation, abdo pain, decreased stool calibre, alternating bowel habit, PR bleed, LI obstruction

Rectum

•Obstruction, tenesmus, bleeding, PR bleeding, palpable mass on rectal exam

Question 8

How should colorectal Ca be non-surgically managed?

Answer 8

Chemo = 5-FU, capecitabine

+/- biological agents cetuximab, panitumumab

Liver mets = surgical, microwave ablation, radiofrequency ablation, radiofrequency-assisted liver resection, selective internal radiation therapy (SIRT)

Adjuvant chemo = for Dukes C or high risk Dukes D

RT = rectal Ca only

Question 9

What is the apple core sign?

Answer 9

Most frequently associated with constriction of the lumen of the colon by a stenosing annular colorectal carcinoma.

Question 10

What are the diff options for post-op analgesia in pts undergoing bowel surgery via laparotomy?

Answer 10

Opioids - PCA

• continuous infusion via epidural

Wound infusion of anaethetic

NSAIDs - ketorolac trometamol (moderate-severe pain)