Management

Preoperative assessment

Colonoscopy is the investigation of choice, but air contrast barium enema and sigmoidoscopy is an alternative to colonoscopy. If colonoscopy is incomplete, barium enema must be included. (Level III evidence)

79% of patients had colonoscopy, 3% had sigmoidoscopy and barium enema and 81% had either or both (Table 17).

Endorectal ultrasound is more accurate than either CT or MRI for assessing the depth of invasion and lymph node status. It is the preferred initial method of locally staging a rectal cancer preoperatively. While endorectal ultrasound is the most accurate method to preoperatively stage rectal cancer locally, it is not necessarily indicated for all rectal cancers. Its main role will be:

•  for advanced (T3–4) rectal cancers where neoadjuvant therapy is being considered;

•  for small cancers in the distal rectum where a local transanal excision may be an alternative to abdomino-perineal excision of the rectum with a permanent colostomy, so accurate assessment of the depth of local tumour invasion and state of the lymph nodes is essential; and

•  if neoadjuvant chemoradiotherapy or a transanal local excision is planned. (No guideline given; quoted from page 64 of the NHMRC guidelines)

61% of patients who underwent surgery for rectal cancer had either CT scanning (59%) or endorectal ultrasound preoperatively (9%). This included: 66% of patients with T3 or T4 rectal cancers (8% had endorectal ultrasound);

89% of patients who had pre-operative radiotherapy (25% had endorectal ultrasound); and 48% of patients who had transanal local excision (18% had endorectal ultrasound) (Table 20).

Preparation for surgery

All patients [having elective surgery for rectal cancer] who have a reasonable chance of a postoperative stoma should be informed about this possibility. This includes a visit, where possible, by the stomal therapy nurse. (Expert opinion)

90% of patients who presented electively and had a stoma created, had been seen by a stomal therapist preoperatively (Table 22).

Randomised trials do not demonstrate a benefit from routine bowel preparation (Level II evidence). If bowel preparation is to be used, then both polyethylene glycol preparation and sodium phosphate preparations are effective, but polyethylene glycol is more acceptable and has lower postoperative complication rates. (Level II evidence)

90% of all patients and 96% of patients treated electively had bowel preparation. An oral preparation alone was used in 86% of all patients (Table 23).

All patients undergoing surgery for colorectal cancer should receive prophylaxis for thromboembolic disease. Unfractionated heparin, low molecular weight heparin, and intermittent calf compression are effective in reducing the incidence of thromboembolism. (Level I evidence)

98% of patients who had surgery for bowel cancer received heparin (fractionated or unfractionated), intermittent calf compression, or both (Table 24).

All patients undergoing colorectal cancer surgery require prophylactic antibiotics. (Level I evidence)

A single preoperative dose of intravenous second or third generation cephalosporin and metronidazole is an effective regime. (Level II evidence)

94% of patients who had surgery for bowel cancer received antibiotics pre-operatively.

A cephalosporin plus imidazole was given to only 28% of patients undergoing surgery (Table 25). 37% of patients who received antibiotic prophylaxis continued this treatment post-operatively (Table 26).

Elective surgery for colon and rectal cancers

For fixed tumours, en bloc resection of primary colonic cancer, together with the attached organ or the abdominal wall, should be performed in an attempt to obtain a curative resection. No attempt should be made to assess if the attachment is benign or malignant at the time of surgery. (Expert opinion)

72% of patients who had a tumour that was adherent to adjacent structures, had this removed en bloc (Table 31).

Bilateral oophorectomy should be performed if there is obvious malignant disease of one or both ovaries. Prophylactic bilateral oophorectomy for colon cancer cannot be supported by the available evidence. (Expert opinion)

5% of women who had surgery for colon cancer had an oophorectomy performed as part of the primary surgical procedure. This procedure was performed with prophylactic intent for 2% (Table 33).

Elective surgery for rectal cancer only

Total excision of distal mesorectum beyond the transection of the rectal wall is not recommended as a routine procedure when resecting rectal cancer until more evidence is available to establish its efficacy. (Expert opinion)

23% of patients who underwent surgery for rectal cancer (excluding the rectosigmoid) did not have the mesorectum completely excised (Table 37).

Local excision of T1 rectal cancer is effective. (Level III evidence)

2.9% of rectal cancer patients underwent local excision, of whom 69% had a T1 tumour (Table 39). 10% of T1 rectal cancers were locally excised.

Sphincter-saving operations should be preferred to abdomino-perineal resection except in the presence of:

•  low-level infiltrating tumours with unfavourable histological grade;

•  tumours such that adequate distal clearance (>2 cm) cannot be achieved (often an operative decision);

•  the sphincter mechanism is not adequate for continence;

•  access to the pelvis makes restoration technically impossible (rare).

(Level III evidence)

Sphincter-conserving surgery was achieved for 70% of patients who had surgery for rectal cancer. This figure was 90% for patients with tumours of the upper and middle thirds of the rectum, and 45% for patients with tumours of the lower third (Table 40).

Where technically feasible, the colonic pouch may be the preferred form of reconstruction after low anterior resection of tumours of the lower half of the rectum to improve short-term postoperative neorectal function. The ideal length of the pouch lies between 5 cm and 8 cm. (Level II evidence)

57% of patients who had sphincter preserving surgery for rectal cancer (excluding the rectosigmoid) had a colonic pouch constructed. For patients who had a pouch constructed, the length was between 5cm and 8cm for 83% (Table 41).

Referral for chemotherapy and radiotherapy

People with resected node-positive colon cancer should be offered adjuvant therapy. (Level I evidence)

59% of patients who had resection for a node-positive bowel cancer received adjuvant chemotherapy; another 16% were considered for the treatment, but did not receive it (Table 46).

Postoperative 5-FU based chemotherapy and radiotherapy (combined modality therapy) is recommended for patients with high-risk rectal cancer. (Level II evidence)

13% of patients with tumours that had penetrated beyond the full thickness of the bowel wall, or involved regional nodes received post-operative combined modality therapy. However, another 12% of these patients received combined modality therapy based on pre-operative radiotherapy (Table 54).

Management of locally advanced rectal cancer

Preoperative radiation therapy, possibly with chemotherapy, is recommended in rectal cancers fixed or tethered within the pelvis if it is felt down-staging will enable successful resection. (Level II evidence)

6% of patients having surgery for locally advanced (Stage T4) tumours underwent preoperative radiotherapy. Another 20% of patients in the same group had preoperative chemotherapy and radiotherapy (Table 56).

Surgery for metastatic colorectal cancer

Patients with up to four lesions that can be safely removed with an adequate margin and have no evidence of extrahepatic disease should be considered for resection. (Level III evidence)

3% of patients presenting with liver metastases at the time of diagnosis of bowel cancer underwent liver resection concurrent with bowel resection (Table 57).

Participation in clinical trials

Doctors should encourage patients with colorectal cancer to consider participating in appropriate clinical trials for which they are eligible. (Expert opinion)

Between 54% and 77% of patients who were eligible for a trial were offered the opportunity to participate. However only 4%-8% of all patients in this survey participated in a trial (Figure 1).

Follow-up intentions

All patients who have undergone surgery for colorectal cancer should have specialist follow up in conjunction with the patient's general practitioner. (Expert opinion)

For 73% to 94% of patients who had had curative surgery, their surgeon intended to be involved in their follow-up (Table 59).