What we do
Treatment Options
As with all tumours there are four options which can be adopted in the management of pseudomyxoma peritonei:
1. Watch and wait
2. Radiotherapy
Radiotherapy does not have a place in the management of pseudomyxoma peritonei, as it would be impossible to
apply radiotherapy to a large area without causing serious damage to the abdominal organs.
3. Chemotherapy
The commonly used forms of chemotherapy (oral or intravenous) have very little role at the benign end of the
spectrum. This is due to the fact that the disease is of borderline malignancy and has a very poor blood
supply, so that chemotherapy does not gain access to the cells. All chemotherapy treatment relies on a
balance between the benefits and risks. For a low grade tumour the risks of treatment far outweigh the
benefits, and therefore the majority of oncologists (chemotherapy specialists) consider that chemotherapy
has no place in the management of early pseudomyxoma peritonei. However intestinal type chemotherapy
sometimes has beneficial effects if the tumour is a mucinous adenocarcinoma.
4. Surgery - broadly of two types:
Debulking - The common surgical approach is debulking to remove as much of the
tumour as possible, and generally includes removal of the uterus and ovaries in the female and often the
right colon and the omentum. Disease recurrence is almost inevitable due to residual and recurrent disease
around the peritoneal cavity. Repeat debulking surgery may be possible on a number of occasions, but each
attempt becomes more difficult and dangerous. The small bowel becomes increasingly involved due to
adhesions following prior surgery and eventually surgery is impossible and is fraught with severe
complications such as small bowel fistulae.
Complete cytoreduction - Complete cytoreduction (complete tumour removal) is a
technique developed and popularised by Professor Paul Sugarbaker at the Washington Cancer Centre.
Average operating time for what is called a 'major peritonectomy' is ten hours. The operation comprises a
number of different procedures, namely:
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Right hemicolectomy |
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Greater omentectomy |
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Splenectomy |
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Cholecystectomy |
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Lesser omentectomy |
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Pelvic peritonectomy, which sometimes includes the rectum by anterior resection and in the female
includes removal of the ovaries and uterus |
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Stripping of the peritoneum from the left hemidiaphragm |
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Stripping of the peritoneum from the right hemidiaphragm |
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Stripping of disease from the surface of the liver |
An important factor at surgery is the involvement of the small bowel. In general the small bowel is not
grossly involved due to small bowel peristalsis (normal movement of the bowel) being relatively protective
against tumour implantation and growth. The best mechanism for determining involvement of the small bowel
prior to surgery at present is a CT scan with a large volume of oral contrast to outline the small bowel.
On the CT scan it is possible to see tumour displacing the small bowel and in the small bowel mesentery -
usually a poor prognostic factor. Most cases have some degree of small bowel involvement but it is usually
possible to deal with limited small bowel disease. If all disease can be removed, heated Mitomycin C is given
directly into the peritoneal cavity at the time of operation at a temperature of approximately 400C.
Intraperitoneal 5FU is often given for four days post-operatively.
Suitability for surgery
Not every case is suitable for surgery for a number of reasons - in particular the extent or distribution of
the disease, or fitness to withstand major high risk surgery. Occasionally it is not possible to determine
the extent of disease adequately until the abdomen has been opened, and therefore it is never possible to
guarantee that complete tumour removal will be achievable.
Post-operative Mortality and Morbidity
Complete cytoreduction carries a mortality risk of 3-5%, which means 1/30 to 1/20 patients die as a direct
result of surgical complications. The main complications are cardio-respiratory (lung infections and heart
failure). There is also a risk of clots in the main leg veins, which can result in pulmonary embolus.
Surgery also has significant morbidity (serious complications) of around 30%. Approximately 20% (1 in 5)
patients require further surgery to deal with the complications of the primary operation during the same
admission. Approximately 20% of patients require a stoma and in half of those the stoma will be permanent.
A permanent stoma is required if all or most of the colon has to be removed.
A temporary stoma is usually used when the rectum has to be removed and the join, although appearing intact at
the time of surgery, has a very high risk of leakage due to the particular position of the anastomosis or
join, and the fact that intraperitoneal chemotherapy is used. The temporary stoma is usually closed
between 3 and 6 months after the primary operation.
Most patients spend about 5 days in intensive care, and the average hospital stay is 28 days.
All patients require feeding by intravenous or total parenteral nutrition (TPN) for an average of 14 days.
More recently feeding has been given through a tube placed into the small bowel at operation, which often
reduces the requirement for intravenous feeding.
If complete tumour removal has been possible, intraperitoneal chemotherapy has been given and the
tumour is at the benign end of the spectrum, 50-80% will have ten year disease free survival
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