pseudomyxoma peritonei (EFO_0007456, an Experimental Factor Ontology entry) can be described as follows. An appendix cancer that is characterized by progressive accumulation of mucus-secreting tumor cells within the abdomen and pelvis. Also known as: Pseudomyxoma Peritonei, Pseudomyxoma peritonei (disorder), Pseudomyxoma peritonei (morphologic abnormality), mucinous Ascites.