The main treatments for pseudomyxoma peritonei (PMP) are surgery and chemotherapy. Your treatment depends on the size of the cancer and your general health.
You might not start treatment straight away. The doctor closely monitors your cancer in case you need treatment in the future. This is called watch and wait.
If you need treatment you might have:
- surgery combined with chemotherapy into the tummy (abdomen)
- surgery to remove as much cancer as possible (debulking surgery)
Wait and watch
Your doctor might decide to closely monitor your cancer if it’s small and slow growing and you don’t currently need treatment. Your doctor will check up on you regularly. Watch and wait can also sometimes be called active surveillance. They do this with blood tests and scans.
You might find it hard to cope with this and struggle with feeling as though no action is being taken.
Surgery combined with chemotherapy into the abdomen
Where possible, you’ll have surgery combined with chemotherapy directly into your abdomen. It's called cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC)
You have to be well enough to have this intensive surgery. And the surgeon needs to be able to remove the disease without affecting your vital organs.
- the surgeon removing any tissue affected by PMP
- having heated chemotherapy drugs directly into your abdomen during the surgery (HIPEC)
The aim is to remove all of the visible PMP cells in your abdomen so there are no cancer cells left that could start to grow again. The surgeon strips out the lining of the abdomen (the peritoneum) and removes any tissues affected by PMP.
The operation varies between people, but can include removing:
- part of the bowel
- the spleen
- cancer attached to the surface of the liver
- the fatty layers in the abdomen (the omentum)
- the gallbladder
- the lowest part of your bowel (rectum)
- the womb and ovaries if you are a woman
- the bellybutton
- the affected lining of your abdomen (peritoneum)
Your spleen helps to fight infection. You might need to have some vaccinations before, or just after, the operation if your surgeon thinks they are likely to remove your spleen. And you will need to take antibiotics for the rest of your life because of changes to your immune system.
This can be major surgery. The operation can take around 10 hours and your recovery can be slow. Sometimes people need more than one operation, several months apart.
During your operation the surgeon puts heated chemotherapy into the peritoneal space inside your abdomen. This is called hyperthermic intraperitoneal chemotherapy, or HIPEC.
Chemotherapy uses anti cancer drugs to destroy cancer cells. The aim is to kill any PMP cells that remain in the abdomen. Heating the chemotherapy can improve how well it works.
You usually have a chemotherapy drug called mitomycin C. You sometimes have other drugs , such as oxaliplatin. You might have more intraperitoneal chemotherapy during the days after your operation. You have this through tubes into your tummy.
You might be in intensive care or a high dependency unit for 24-48 hours. You might also have:
- a catheter (tube in the bladder)
- an epidural (tube in the spine for pain relief)
- a nasogastric tube (tube down your nose into your stomach to stop you being sick)
- drains in the tummy
You’re likely to be in hospital for 2 weeks. Some patients may also require a blood transfusion after the operation. It takes a long time to be able to recover from this operation. It can be at least 6 months before you are fully active again and able to work.
About 30 out of every 100 people (30%) have complication after treatment, although this might be less in some treatment centres. About 20 out of 100 patients (20%) need a stoma after surgery. A stoma is where the bowel is brought out to the surface of the tummy and covered by a bag after surgery. But about half of these people only need the stoma for 3 to 6 months, after which the bowel is put back together.
The National Institute for Health and Care Excellence (NICE) has produced guidance on this intensive surgery with intraperitoneal chemotherapy.
Doctors must discuss the risks and benefits of the treatment with you before you consent to this surgery.
Debulking surgery aims to remove as much of the cancer as possible, rather than removing the cancer completely.
Debulking surgery can be done to make a diagnosis and get samples of the tumour. It can also remove mucin. It won’t cure PMP but might ease your symptoms. It could also mean that you can then have the cytoreductive surgery with HIPEC.
Debulking surgery might mean removing part of your bowel and if you are woman, removing your womb and ovaries.
Unless the surgeon can remove the whole cancer, it's very likely to come back. Because of this you might have debulking surgery more than once.
You might have chemotherapy if you can’t have surgery. You are more likely to have chemotherapy if:
- your cancer is causing symptoms
- CT scans show your cancer is growing quickly
You might have either mitomycin C into a vein with or without capecitabine as tablets. Doctors sometimes use other drugs.
It is important that you discuss the pros and cons of having treatment with your specialist. Your cancer might be slow growing. The doctor might suggest that they monitor you closely and only recommend chemotherapy if your cancer is growing quickly or causing symptoms.
There hasn't yet been enough research into the benefits of systemic chemotherapy (chemotherapy to your whole body) for PMP.
Specialist centres for pseudomyxoma peritonei
The National Institute for Health and Care Excellence (NICE) has produced guidance on cytoreductive surgery with intraperitoneal chemotherapy. They recommend people with PMP are treated in a specialist centre.
Because pseudomyxoma peritonei is very rare, there are 2 designated UK specialist treatment centres.
These are at the Peritoneal Malignancy Institute at Basingstoke and North Hampshire NHS Foundation Trust and the Colorectal and Peritoneal Oncology Centre at The Christie Hospital in Manchester.
A lot of people with pseudomyxoma peritonei will have already had surgery at another hospital because PMP wasn't suspected to begin with. Even if you have already had surgery, your specialist might recommend further surgery, followed by intraperitoneal chemotherapy.
Research into treatment
Researchers and doctors around the world are continually trying to improve treatments for pseudomyxoma peritonei. But because this type of cancer is so rare, it makes it difficult to carry out trials.
- looking at different ways of performing surgery for early cancers
- researching drugs for treating PMP
- studying PMP cells under the microscope
Where to get support and information
It can be very difficult to find support if you have a rare type of cancer. You are likely to find people at your local cancer support group who share your experience of being diagnosed with cancer and possibly of having major surgery. But you may want to try to contact other people who have the same condition as you.
If you want to find people to share experiences with online, you could use Cancer Chat, our online forum.
Pseudomyxoma Survivor is a registered charity that offers a befriending service as well as practical and emotional support to people affected by PMP.