OBJECTIVEThe clinicopathologic and immunohistochemical features of 11 pseudomyxoma peritonei (PMP) cases were studied to determine pathologic diagnosis, site of origin and prognosis.

METHODSClinical files of 11 cases of PMP were reviewed with follow up. The changes in mucinous tumors of peritoneum and primary tumors under microscope and immunostaining were reviewed.

RESULTSEleven cases (8 women, 3 men) are reported. The patients age ranged from 36 to 76 (average 56). One died 2 years after operation, and one case was lost. The remaining 8 cases were alive 1 to 60 months postoperatively. Of the 11 cases, 8 cases had appendiceal mucinous neoplasm of the 11 cases, and 5 women had synchronous ovarian mucinous tumors; colon mucinous adenocarcinoma was present in one case with synchronous ovarian mucinous tumor; simple ovarian mucinous tumors were present in two cases. Immunostainings were consistent on mucinous tumors of appendix, ovary and peritoneum in the same case.

CONCLUSIONSTo diagnose the PMP, the type of tumor should be considered whether it is benign, low malignant or malignant. The appendix neoplasm is closely related to PMP. The prognosis depends greatly on the growth speed of the mucinous neoplasm.