Pseudomyxoma peritonei (PMP)

What is pseudomyxoma peritonei (PMP)?

Pseudomyxoma peritonei (PMP) is a rare cancer. It usually starts in the appendix. But it can start in:

Position of appendix and other organs in bowel

This diagram shows the position of the appendix and other organs in the bowel
Image: The diagram shows the position of the stomach, small bowel, large bowel, rectum and anus. The stomach is just below the rib cage to the left of the body. Below the stomach is the small bowel which is a long tube that is folded within the abdomen and leads to the large bowel. The large bowel is a wider tube that surrounds the small bowel. The large bowel starts on the lower right side of the body. There is a thin short tube attached at this side of the large bowel. This is the appendix. The large bowel goes up the right side of the abdomen, then across the top and down the left side. At this point it becomes wider to form the rectum. At the lower end of the rectum is a narrow tube. The narrow tube is the anus where the bowel opens to the outside of the body.

The tumour usually grows slowly. But as it grows, it can spread from where it started into other parts of the tummy area (abdomen).

Unlike other cancer types, PMP rarely spreads through the bloodstream or lymphatic system. Instead, PMP cells attach to the layer of tissue that lines the inside of the abdomen. This is called the peritoneum. The peritoneum covers and protects the organs in the abdomen, such as the bowel. It also makes gaps around the organs. These gaps are called the peritoneal space.

PMP cells make a jelly-like substance called mucin. The mucin collects in the peritoneum. This is why PMP is sometimes called ‘jelly belly’.

Side view of ovary, peritoneal space and peritoneum in female body

Side view of female organs
Image: The diagram is a side view of a female body from below the chest down to the upper thigh. It shows the structures and organs in the abdomen and pelvis. It shows the position of the large bowel, omentum, ovary, womb and bladder. The pelvis is the lower part of tummy (abdomen). The bladder is at the bottom of the pelvis. The womb is above and behind the bladder. Above the bladder and womb, is a long, folded tube. This is the large bowel. A long flap of tissue is hanging down in front of the large bowel. This is the omentum. Above the large bowel is a round structure, which is the stomach. Above the stomach is a large organ, which is the liver. There is a thin lining around the liver, stomach, large bowel, omentum, ovaries and womb. This lining is the peritoneum. The space around the structures that are lined and the peritoneum is called the peritoneal space. A line of connecting bones are shown along the curve of the back down. This is the spine.

PMP usually stays within the peritoneal space. But eventually the build-up of mucin puts pressure on the bowel and other organs.

Symptoms of PMP

PMP may not cause any symptoms in its early stage. Symptoms of PMP include:

  • a gradual increase in waist size
  • a hernia (a bulge on the tummy wall)
  • loss of appetite
  • unexplained weight gain
  • tummy pain (abdominal pain)
  • pelvic pain
  • a change in bowel habit – for example, diarrhoea, constipation or leaking (incontinence).

What causes PMP?

Doctors do not know what causes PMP.

Diagnosis of PMP

PMP is rare, and it can be difficult to diagnose. You may have some symptoms, but these can be caused by many other medical conditions. Your GP may arrange tests in a hospital to find out what is causing your symptoms. PMP may be found during abdominal surgery for other medical conditions.

The following hospital tests may be used to diagnose PMP:

  • CT scan

    A CT scan uses x-rays to build a three-dimensional (3D) picture of the inside of the body.

  • Ultrasound scan

    An ultrasound scan uses sound waves to build up a picture of the internal organs onto a computer screen.

  • Drainage of fluid from the abdomen (peritoneal aspiration)

    A doctor may take a sample of fluid from the tummy so that it can be tested. The doctor will numb the skin over the area first with a local anaesthetic. They then pass a needle through the skin into the peritoneal space. They use the needle to draw some of the fluid into a syringe.

  • CT-guided biopsy or ultrasound-guided biopsy

    You may also have a biopsy using a CT scan to help find the abnormal area. A biopsy is when a doctor removes a small piece of tissue or cells. Another doctor called a pathologist then examines the tissue or cells under a microscope to look for signs of cancer.

    You will have a local anaesthetic to numb the area before the biopsy starts. A doctor then passes a needle through the skin. They use an ultrasound or a CT scan to check the needle is in the right place. The needle has a tip that can cut out a small piece of tissue.

  • Surgery

    You may have a biopsy taken during keyhole surgery (laparoscopy). Before surgery, you may have a general anaesthetic. Or you may have a local anaesthetic and a drug to make you feel relaxed and sleepy.

    During surgery, the surgeon makes a small cut in your tummy. They then use a special instrument called a laparoscope to look around inside your tummy. A laparoscope is a thin tube with an eyepiece at 1 end and a light and camera at the other end. The surgeon then uses another instrument to take a small piece of tissue.

Waiting for test results can be a difficult time. We have more information that can help.

Treatment for PMP

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).

Your doctor or cancer specialist or nurse will explain the different treatments and their side effects. They will also talk to you about things to consider when making treatment decisions.

The main treatments for PMP are:

  • surgery
  • heated chemotherapy given directly into the peritoneum. Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells.

Heated chemotherapy is also called hyperthermic intraperitoneal chemotherapy (HIPEC).

Your treatment may depend on how far the PMP has spread and your general health.

Cytoreductive surgery with HIPEC

You may be offered surgery to remove as much of the PMP as possible. This is called cytoreductive surgery. You will then have a heated chemotherapy treatment directly into the peritoneal space. This is called hyperthermic intraperitoneal chemotherapy (HIPEC). It washes out any remaining PMP cells.

Having cytoreductive surgery with HIPEC is also called the Sugarbaker technique, after the surgeon who developed it. It is major surgery, so it is important to discuss with specialist doctors whether it is suitable for you.

The aim of this treatment is to remove as much of the PMP as possible and reduce the risk of it coming back.

During the operation, your surgeon may also remove:

When the surgeon has removed all signs of PMP, they put a heated chemotherapy liquid into the peritoneal space. The aim of this treatment is to kill any cancer cells that are left behind. After 60 to 90 minutes, the chemotherapy liquid is drained from the tummy and the surgeon finishes the operation.

Where will I have my treatment?

Only 2 centres in the UK offer specialist surgical treatment for PMP. This is because it is a rare cancer.

The 2 centres that do cytoreductive surgery with HIPEC are:

If you have a long distance to travel to either of these centres, you may need to stay in hospital for longer.

If you are having chemotherapy into a vein (intravenously), you can have it at your local cancer treatment centre.

Before surgery

Before your operation your surgeon and specialist nurse will talk you about the operation They will tell you what to expect and how you can prepare for surgery. We have more information about preparing for surgery.

After surgery

After surgery, you will stay in hospital for about 2 to 3 weeks. For the first few days you will be in a critical care unit. The nurses will help you to get up and to move around. You will have different tubes such as a drip or intravenous infusion to give you fluids until you are able to eat and drink normally. You will also have painkillers which may be given into a vein to begin with.

We have more information about what happens after surgery.

If you need a stoma

If you have had part of the bowel removed, your surgeon may create a stoma as part of the operation. A stoma is an opening that is made through the tummy wall (abdominal wall). It connects the bowel to the surface of the tummy.

Having a stoma means stools (poo) will not pass out of the back passage (rectum) in the usual way. Instead they will pass out of the stoma, into a disposable bag you wear over the stoma. If you are going to have a stoma, you will meet a stoma care nurse before your operation. They will explain what is involved and give you a lot of support.

The stoma may be temporary. This means it can be reversed when you have fully recovered from surgery. This can take 3 to 6 months. Some stomas are permanent.

A colostomy and colostomy bag
This diagram shows the position of a colostomy stoma and bag and the position of the bowel
Image: The diagram shows a person’s chest down to the thighs. It shows the position of the bowel within the abdomen (tummy). On the left-hand side of the tummy, the bowel comes to the surface of the tummy. This is the stoma. The stoma is covered with a stoma bag that hangs down with a sealed end.

Fertility after cytoreductive surgery with HIPEC

Cytoreductive surgery with HIPEC treatment may affect your fertility.

If you have your womb and ovaries removed (hysterectomy and bilateral oophorectomy), you will not be able to get pregnant.

If you are hoping to get pregnant in the future, you should discuss this with your consultant or clinical nurse specialist (CNS). They can talk to you about possible ways to preserve your fertility and can refer you to a fertility expert.

Some cancer treatments can affect whether you can get pregnant or make someone pregnant. Before cancer treatment, it may be possible to store sperm or eggs so that they can be used later. We have more information about fertility.

Chemotherapy

If you cannot have surgery, you may have chemotherapy. This aims to slow the growth of PMP and reduce symptoms. You have chemotherapy as tablets or as a drip (infusion) into a vein.

Watchful waiting

If the PMP is small or growing slowly, you may not need to start treatment straight away.

Your doctor may suggest watchful waiting. Sometimes this is called active surveillance.

This means you will have CT scansblood tests and regular check-ups to monitor the PMP and your symptoms. If the PMP begins to cause you problems, your doctor will talk to you about starting treatment.

Clinical trials

You may have some treatments as part of a clinical trial. Because PMP is rare, there may not always be a trial in progress. Your doctor or nurse can tell you more about this.

After PMP treatment

Follow-up after treatment for PMP

You will have regular check-ups during and after your treatment. Tell your doctor or specialist nurse as soon as possible if you have any problems or notice new symptoms between appointments.

We have more information about follow-up care after treatment.

Side effects after PMP treatment

You may have some ongoing side effects as you recover from PMP treatment. You can use our impacts of cancer A to Z to search for information about managing different symptoms and side effects.

Sex life

PMP and its treatment can affect your sex life. Changes may get better over time, but sometimes they are permanent. If you have any problems or are worried about this talk to your doctor or nurse. They can explain what to expect and there are often things that can help. We have more information about sex and cancer.

Body image

PMP and its treatments can cause changes to your body that affect how you think and feel about your body (body image). We have more information about managing body image concerns.

Well-being and recovery

It can take time to recover after PMP treatment. Some days you may feel better than others.

Looking after yourself can help speed up your recovery. Even small changes may improve your well-being.

Even if you already have a healthy lifestyle, you may choose to make some positive changes after treatment. We have more information on leading a healthy lifestyle after treatment.

It is important to know where to get support or information if you need it. People often need support even some time after PMP treatment. But sometimes it is difficult to know who to ask for help. To find support:

  • ask your GP or someone from your cancer team for advice about support in your area
  • search cancercaremap.org to find cancer support services near you
  • call us free on 0808 808 00 00 or talk to us talk to us online - our cancer information and support specialists can offer guidance and help you find what you need.

Support after PMP

Some people with a rare type of cancer may find it helpful to talk to someone with the same condition. Your cancer doctor or specialist nurse may be able to put you in touch with someone who has PMP and is happy to speak to others. The support network Pseudomyxoma Survivor can also help with this.

The Christie and Basingstoke hospitals each hold annual support days specifically for PMP patients and their relatives. Your specialist nurse at the Christie or Basingstoke can tell you more about this. They will also offer you advice and support.

Macmillan is also here to support you. If you would like to talk, you can:

Other organisations who offer information and support include:

About our information

This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer.

  • References

    Below is a sample of the sources used in our pseudomyxoma peritonei (PMP) information. If you would like more information about the sources we use, please contact us at

    informationproductionteam@macmillan.org.uk

     

    K Govaerts, R J Lurvink, IHJT De Hingh et al. Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment. 2020. European Journal of Surgical Oncology. Available from: www.pubmed.ncbi.nlm.nih.gov/32199769 [accessed January 2023].

     

    YL Lin, DZ Xu, XB Li et al. Consensuses and controversies on pseudomyxoma peritonei: a review of the published consensus statements and guidelines. 2021. Orphanet Journal of Rare Diseases 16, 85 (2021). Available from: https://ojrd.biomedcentral.com/articles/10.1186/s13023-021-01723-6 [accessed January 2023].

Dr Paul Ross SME

Dr Paul Ross

Reviewer

Consultant Medical Oncologist

Guy's and St Thomas' NHS Foundation Trust

Date reviewed

Reviewed: 01 May 2024
|
Next review: 01 May 2027
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

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