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Name l Define l Risk l Detect l Treatment l Stage/Grade l Followup l Mets/Recur l Link
Pseudomyxoma Peritonei, PMP, and jelly-belly.
This is a very rare disease that continues to create controversy among the medical community regarding definition, pathology, site of origin, and prognosis. It is believed that Pseudomyxoma peritonei results from ovarian and/or appendiceal mucinous tumors. Cyst rupture results in intraabdominal mucin accumulation, leading to abdominal distension.
Pseudomyxoma peritonei is an uncommon, progressive, clinical syndrome characterized by the presence of high viscosity, mucinous, material that is commonly associated with an existing abdominal neoplasm. Neoplasms usually involved, in order of occurrence, are primary tumors of the appendix, ovary, or pancreas. Pseudomyxoma peritonei rarely results from a ruptured primary ovarian mucinous neoplasm, but often produces secondary borderline-like ovarian tumors with prominent pseudomyxoma ovarii.
PMP's mucinous material has a tendency to both float and adhere to the serosal surfaces, hence the 'jelly-belly' effect. If left untreated, this mucinous material will eventually fill the peritoneal cavity and start compressing vital structures. There are at least three distinct groups of PMP lesions described in literature.
1. The first is described histologically as a diffuse benign mucinous epithelium
associated with an adenoma of the appendix. This is associated with fibrosis.
2. The second group has the pathological features of a disseminated carcinoma with
a poor prognosis and this group should be diagnosed as ‘disseminated
peritoneal mucinous carcinomatosis’.
3. The third group includes those uncommon cases with pathological features that
have similarities with both of the above groups. These cases are usually
associated with primary well-differentiated mucinous adenocarcinomas of the
appendix.
In retrospective studies, the only predominant attribute was age, with a mean age of 59. This syndrome is caused by a pre-existing neoplasm (benign or malignant), that may, or may not have been diagnosed previously.
This disease, sadly, does not have many signs or symptoms; so diagnosis often occurs after the disease has progressed. The patient may notice an unexplained increase in weight and the overall size of the abdominal area. Ironically, the increased pressure caused by this syndrome might lead to an inability to eat.
PMP is commonly diagnosed, incidentally, while treating another disease (such as appendicitis) or while having a CT or ultrasound of the abdomen. Laparotomy is the main tool for diagnosing pseudomyxoma peritonei.
If left untreated, PMP is fatal. Cytoreductive surgery (referred to as 'debulking') is commonly the primary treatment for pseudomyxoma peritonei. Complete surgical excision of PMP often requires removal of non-life-threatening organs and body structures, such as the female uterus and ovaries; sections of the colon; and the omentum. Hyperthermic intraperitoneal chemotherapy (HIPEC), after cytoreduction, seems to be the current 'gold standard' of treatment for PMP; although choice of institution and treating surgeon greatly influence the outcome. Recently, doctors in Japan's Kinki Univ of Med have found that laparoscopic surgery, a minimally invasive procedure, greatly improves the quality of life of patients with PMP.
Most cases of pseudomyxoma peritonei are considered malignant diseases. Normally it is slow growing; but extremely aggressive cases have been reported. Low-grade pathologic subtypes, and complete cytoreduction has a positive effect on the overall survival time of PMP patients. Even in survival, PMP may be a recurring chronic disease that requires surgical intervention and treatment.
PMP must be followed closely after discovery and even after mulitple treatment sessions.
Complete surgical removal of PMP is extremely hard to accomplish Residual disease is common, therefore a recurrence of symptoms occurs often. Treatment of recurrence is normally done with surgical removal, if at all possible.