Editing Colon cancer (section)

== '''Complications''' ==

** Obstructing cancers
*** '''Approach'''
**** Surgery
**** Stent (see below for left-sided cancers)
***** Bridge to surgery only
***** Reduces stoma rates from 69% to 45%
*** '''Timing of intervention'''
**** Expedited if caecal tenderness, signs of sepsis or caecal diameter >12cm
**** Otherwise prefer using experienced staff during daylight hours
*** '''Principles of surgery'''
**** Colonic decompression
***** Often done at start of case - use either a 19G needle on suction or a Foley
***** If no caecal injury, may allow left-sided segmental resection
**** Anastomosis?
***** If proximal bowel viable, segmental resection with primary anastomosis (unless there is a contraindication, in which case do Hartmann procedure)
***** Leak rates 2-8% (similar to elective surgery)
***** Consider diverting ileostomy, but does not decrease leak rates, just leaks requiring operation
***** Companion series suggests defunctioning in most cases
***** If unwell, just do a Hartmann's; and if seriously compromised physiology is present, just defunction
*** '''Choice of operation'''
**** '''Right-sided, up to and including splenic flexure'''
***** Oncological segmental resection - right hemicolectomy
***** Most cases can have primary anastomosis, but consider diversion for those at risk of failure
**** '''Left-sided'''
***** Options
****** '''Resect''' (Hartmann's (wouldn't survive a leak, or too high risk for leak), or primary anastomosis +/- proximal diversion)
******* Resectable tumour, curative intent
******* Resectable tumour, not much metastatic disease and prospect of survival
****** '''Divert'''
******* Unresectable primary tumour
******* Obstructing rectal cancer
******* Widespread metastatic disease
******* Major comorbidities precluding resection
****** '''Stent'''
******* May permit higher rates of primary anastomosis, decreased wound infections and a lower rate of conversion. Mainly in high-risk or unwell patients. Contraindicated in suspected ischaemic or perforated bowel. See separate topic.
** Perforation
*** Usually occurs in the caecum (Laplace), but can also be at the tumour or in a segment of diverticulitis proximal to the tumour
*** Contained perf: drain percutaneously followed by semi-elective surgery
*** Free perf: surgical emergency. Resection with proximal colostomy or ileostomy (Hartmann's). Can possibly MAYBE do primary anastomosis with covering loop ileostomy.