For more than a century and up until just a few years ago, a permanent colostomy was considered to be de rigueur in the treatment of colorectal cancer.
In this procedure, the diseased section of the colon is removed (a colectomy), and the functioning end - the part of the colon that is still attached to the upper digestive tract (the throat, oesophagus, stomach and duodenum, the first part of the small intestine) - is brought onto the surface of the abdomen through an incision.
This end of the colon is then attached to the skin, creating a permanent opening in the abdomen called a 'stoma'. Stools are re-routed through the stoma and collected in a bag attached to the mouth of the colonic opening. The lower end of the colon - the part that leads to the rectum and anus - is then either removed or sutured shut, and left in the abdomen.
The patient will never again have a normal bowel function, but will have to be resigned to a lifetime of colostomy bags.
Quality of life and other complications
As if that's not bad enough, such a drastic surgical measure doesn't come without further disadvantages. While many patients may manage to get used to living permanently with a colostomy bag, a significant number will experience physical as well as psychological distress.
In a study looking into the quality of life among patients who had permanent stomas, 80 per cent of the near-400 respondents said they have had to make changes in their lifestyle, and more than 40 per cent also had problems with their sex lives (Dis Colon Rectum, 1999; 42: 1569-74). Many of these patients also complain of irregular stools, diarrhoea, uncontrolled passing of gas and urological problems (Acta Chir Iugosl, 2002; 49: 45-55).
Stomal complications have also been reported, the most common being the development of hernias following a permanent colostomy. One study estimated the incidence of parastomal hernias to fall between 4.0 and 48.1 per cent of patients (Br J Surg, 2003; 90: 784-93). Other complications include:
* skin irritation, as a result of diarrhoea not being properly drained and leaking from out of the bag
* fungal infection, commonly caused by Candida albicans
* stenosis, or the narrowing of the stoma, brought on by scarring or infection around the opening
* prolapse, when the stoma stretches to the point where it protrudes beyond the surface of the abdominal skin.
Temporary and permanent stomas
Fortunately, with the advent of advanced surgical techniques that enable surgeons to preserve sphincter function, permanent colostomies are becoming less and less justifiable. In fact, various research now suggests that a permanent colostomy is required in only about 10-15 per cent of colorectal cancer cases.
Temporary stomas are now being favoured over permanent ones. These are often used for patients with other sorts of bowel problems, such as Crohn's disease (a chronic inflammatory condition of the digestive tract, often associated with autoimmune disease elsewhere in the body such as rheumatoid arthritis) and diverticulitis (where the colon develops bulging pouches, and the pouches become infected).
With a temporary colostomy, a stoma is used to re-route waste matter away from the injured or diseased section of the colon to allow the tissues to 'rest' and heal.
But once the colon has recovered, a second operation is carried out to reattach the colon and close the stoma, after which the patient should then be able to resume normal bowel function.
There are two methods by which a temporary stoma can be created:
* Loop colostomy. In this procedure, a loop of colon is brought through a surgical cut in the abdominal wall. The surgeon slips a plastic rod between the loop and the abdomen to hold it in place. An incision is made in the bowel through which stool will pass into a colostomy bag, away from the area of colon that needs to heal. The supporting rod is removed after healing has occurred and the stoma is closed.
* Double-barrel colostomy. In this operation, the surgeon creates two separate stomas on the abdominal wall - one for draining stool, the other for draining small amounts of mucous material. Both stomas are closed when the colon has recovered.
What doctors don't tell you
While it's natural to think that a temporary colostomy would be better than a permanent one, don't be fooled. Closure of the stoma is itself a major operation, and there are significant complications involved.
* The success rate is poor - only around 50 per cent. The remaining half of patients won't have proper closure of the colostomy, and will wind up with a permanent stoma (Dis Colon Rectum, 1996; 39: 1227-31).
* The chances of developing complications are rather high. The rate of complications associated with colostomy closure can be anything from 12 per cent (S Afr J Surg, 1998; 36: 57-9) to 44 per cent (Br J Surg, 1976; 63: 397-9). The median complication rate is around 32 per cent.
* Stomal complications in temporary colostomies are significant in 19.2 per cent of cases, and the type of complications are similar to those of permanent colostomies, including hernia, stenosis, retraction and prolapse (Dis Colon Rectum, 1996; 39: 1227-31).
* Other complications linked to colostomy closure include congestive heart failure, cerebrovascular accident, pneumonia, enterocutaneous and faecal fistulas (abnormal openings between the colon and skin), fatal pulmonary embolism and bowel obstruction (Dis Colon Rectum, 1996; 39: 605-9; Br J Surg, 1976; 63: 397-9).
* Surgery to close a colostomy carries a small risk of death - ranging from 1.3 per cent (Am Surg, 1999; 65: 266-9) to 9.6 per cent (Dis Colon Rectum, 1996; 39: 1227-31).
* Diabetic patients run a significantly higher risk of adverse outcomes in colostomy closure (Am Surg, 1999; 65: 266-9). Other factors which have a cumulative effect on the rate of other