Colorectal Cancer

Question 1

Right colon cancer

Answer 1

Right hemicolectomy
Ileo-colic anastamosis
<5% risk of leak

Question 2

Transverse colon cancer

Answer 2

Extended right hemicolectomy
Ileo-colic anastamosis
<5% risk of leak

Question 3

Splenic flexure cancer

Answer 3

Extended right hemicolectomy
Ileo-colic anastamosis
<5% risk of leak
OR
Left hemicolectomy
Colo-colic anastamosis
2-5% risk of leak

Question 4

Left colon cancer

Answer 4

Left hemicolectomy
Colo-colic anastamosis
2-5% risk of leak

Question 5

Sigmoid colon cancer

Answer 5

High anterior resection
Colo-rectal anastamosis
5% risk of leak

Question 6

Upper rectal cancer

Answer 6

Anterior resection (TME)
Colo-rectal anastamosis
5% risk of anastamosis

Question 7

Lower rectal cancer

Answer 7

Anterior resection (low TME)
Colo-rectal anastamosis +/- defunctioning stoma
10% risk of leak

Question 8

Anal verge cancer

Answer 8

Abdomino-perineal excision of colon and rectum (APER)
No anastamosis
No risk of leak

Question 9

Rectal cancer

Answer 9

In the rectum a 2cm distal clearance margin is required and this may also impact on the procedure chosen.
In addition to excision of the rectal tube an integral part of the procedure is a meticulous dissection of the mesorectal fat and lymph nodes (total mesorectal excision/ TME).
Patients with T1, 2 and 3 /N0 disease on imaging do not require irradiation and should proceed straight to surgery. Patients with T4 disease will typically have long course chemo radiotherapy.
Patients presenting with large bowel obstruction from rectal cancer should not undergo resectional surgery without staging as primary treatment (very different from colonic cancer) because rectal surgery is more technically demanding, the anastomotic leak rate is higher and the danger of a positive resection margin in an unstaged patient is high. Therefore patients with obstructing rectal cancer should have a defunctioning loop colostomy.