Evidence-based treatment of patients with acute large bowel obstruction caused by colon cancer of the left colon: Applying a clinical decision guideline

This is a Dutch, multicenter, prospective validation study of a clinical decision guideline for the treatment of patients with acute, left-sided, colonic cancer obstruction. According to the guideline, patients are divided into three groups:

1) Patients younger than 70 years will have emergency resection. Exceptions can be made for those who have an indication for neo-adjuvant treatment, severe comorbidities and incurable metastatic disease; they should receive a decompressing intervention.

2) Potentially curable patients of 70 years and older will have bridge to surgery treatment by colonic stent placement or transverse loop colostomy, depending on the stricture characteristics and the intention to start anti-angiogenic therapy.

3) Patients with incurable extensive metastatic disease or patients who are unfit to undergo surgical resection will be treated palliatively by stent placement or a diverting colostomy.

The primary outcome is 30-day mortality in the group of elderly patients (≥ 70 years).

Elderly patients of 70 years and older with acute malignant left-sided colonic obstruction will have a better treatment outcome with the ‘bridge to surgery’ method by means of a colonic stent or transverse colostomy.

Primary and secondary outcomes will be measured during hospital admission and during regular oncologic follow-up visits at the outpatient clinic according to the Dutch guideline on colorectal carcinoma.

1. Patients younger than 70 years will have surgical resection. Exceptions can be made for those who have (1) an indication for neo-adjuvant treatment, (2) severe comorbidities, and (3) incurable metastatic disease; they should receive a decompressing intervention.

2. Patients aged 70 years and older without incurable metastatic disease will initially have non-resectional decompression followed by elective resection (bridge to surgery treatment):

A) Patients with a malignant stenosis < 40 mm are eligible for colonic stent placement, which will be performed by an experienced gastroenterologist.

B) If stent insertion failed, if stricture characteristics are unfavourable for stent placement, or if systemic anti-angiogenic therapy is intended, a minimally invasive transverse loop colostomy is constructed.

Patients eligible for elective resection will be operated at least 7 days after initial decompression and no later than 4 weeks after initial presentation.

3. Patients of all ages with incurable extensive metastatic disease or patients who are unfit to undergo surgical resection will be treated palliatively by stent placement or a diverting colostomy. Patients who are fit enough to have palliative chemotherapy are best treated with a colostomy in case anti-angiogenic therapy will be administered because of the risk of tumour perforation when having a stent in situ.