|Patient with advanced pseudomyxoma peritonei. Click to enlarge.
Symptoms depend on the organs involved.
In mildly malignant tumors the following symptoms are characteristic:
- growth of the abdomen with uncharacteristic bloating or pain. In extreme cases, pressure in the diaphragm can cause incapacitating dyspnea, and susceptibilty for complications such as aspiration pneumonia and deep vein thrombosis/lung embolism
- polyuria from pressure on the bladder
- ileus due to compression of segment of the intestines
- pain resembling the symptoms of appendicitis
- hernia with tumor due to intra-abdominal pressure caused by mucous volume
- metastases to the ovaries (often diagnosed as primary ovarian cancer)
The clinical profile of pseudomyxoma peritonei is normally increasing abdominal circumference and confirmation of mucous in the abdominal cavity (jelly belly). But, disease history including appendicitis or mucous as coincidental finding are alternative forms of presentation. Distribution of mucous in the abdominal cavity is characteristic. Mucous and attached tumor are usually observed:
in the greater omentum
under the right diaphragm
in the paracolic gutters bilaterally
around the liver and gallbladder
in the abdominal cavity
With advanced disease, tumor is also seen under the left diaphragm, omental bursa and the small intestine.
Few, slightly atypical epithelial cells are often seen in the mucous. Both ovaries are often involved. It was previously thought that tumor originated from the ovaries, but immunohistochemical examinations indicate that tumor in the ovaries is due to metastasis. Tumor is often therefore misinterpreted as low-grade ovarian cancer. The appendix is usually the origin, but other primary localizations have been reported.
More malignant tumors have a tendency to present with specific organ symptoms due to infiltration.