Mucinous Tumors of the Appendix Associated with Mucinous Tumors of the Ovary and Pseudomyxoma Peritonei: A Clinicopathologic Analysis of 5 Cases Supporting an Appendiceal Origin

ABSTRACT

Pseudomyxoma peritonei often have synchronous appendiceal and ovarian mucinous tumors. There has been considerable debate as to whether the ovarian tumors are secondary to the appendiceal tumor or they are independent primary ovarian tumors. It is important to reveal the primary site for treatment and prognosis of a patient. Five cases of synchronous mucinous tumors of the ovary and appendix were studied. Four cases had pseudomyxoma peritonei and pseudomyxoma ovarii. The ovarian tumors were bilateral in two cases, right in two, and left in one. The ovarian tumors were four mucinous cystadenoma of borderine malignancy and one mucinous cystadenocarcinoma, and the appendiceal tumors consisted of four mucinous tumors of borderline malignancy and one mucinous adenocarcinoma. The histology of the ovarian and appendiceal tumors was similar. Rupture of the tumor was seen in all appendiceal tumors and two ovarian tumors. It has been reported that cytokeratin 7 is a useful marker for distinguishing primary ovarian neoplasms from metastases of intestinal origin. All ovarian and appendiceal tumors showed positive reaction for broad-spectrum cytokeratin, but negative for cytokeratin 7. Based on the clinicopathologic and immunohistochemical features, it should be considered that the appendiceal tumors are primary and ovarian tumors are secondary in the synchronous presentation of the ovarian and appendiceal mucinous tumors.