Pseudomyxoma Peritonei (PMP) is a rare, semi malignant or malignant tumour characterised by progressive accumulation of jelly like substance (mucous) within the abdomen and pelvis, giving rise to the common name ‘jelly belly’. It is thought that most PMP starts in the appendix, although other primary sites include the ovary, bowel and pancreas. PMP is sometimes also called diffuse peritoneal adenomucinosis (DPAM).
Unlike most cancers, PMP doesn’t have the ability to invade organs or spread via the lymphatic system or the bloodstream to distant locations within the body. The tumour itself therefore is not particularly harmful, but there is limited space in the abdomen. If left untreated, the “jelly” will eventually build up to the point where it squashes vital organs within the abdomen (e.g. bowel, liver, kidneys) thereby causing problems/failure.
What are the reasons for recommending Peritonectomy?
We have recommended this treatment program for you because it has the best published results in the medical literature.
An international review of over 2000 patients, including patients from our unit and review of the literature, has identified that for patients receiving peritonectomy and HIPEC, the chances of living 5 years after surgery are 80-90% and the chances of living 10 years after surgery are 70-80%. Of the patients who are alive at 10 years approximately 30% will be living with relapsed/recurrent disease.
The chemotherapy we use is normally mitomycin C for HIPEC and 5-fluorouracil for EPIC.
What are the alternatives?
The alternatives to peritonectomy and HIPEC are as follows:
1. Supportive Care or No Intervention:
If left untreated then pseudomyxoma results in progressive accumulation of jelly in the abdomen. This leads to abdominal discomfort, weight loss, bowel obstructions and ultimately death. This process can take place over months or years. Some individuals are not fit for surgery and this may be the recommended approach.
2. Serial Debulking:
The main surgical alternative to peritonectomy and HIPEC is to do as minimal surgery as required to control symptoms. This is termed ‘serial debulking’. The expectation is that a number of operations will be required over time, and the aim of each operation is not to remove the tumour entirely, but rather to do the minimum amount in order to control symptoms.
Chemotherapy is sometimes used for pseudomyxoma and occasional responses do However overall this is an ineffective treatment as it does not treat the accumulated jelly and the jelly interferes with chemotherapy. In patients whom the pseudomyxoma has transformed into a more aggressive cancer, chemotherapy may be more useful.
Potentially you may be suitable for a trial, your surgeon or oncologist may be able to provide further information if it is appropriate.