The Pathogenesis of Ovarian Myxoma

Abstract

Ovarian myxoma is a rare distinctive benign ovarian stromal neoplasm that occurs predominantly in young women and is hormonally inactive. Although typically classified as an ovarian stromal tumor, its exact pathogenesis remains uncertain. We report 4 cases of ovarian myxoma, 3 of which were associated with another type or other types of ovarian stromal tumor and 1 occurred as a pure myxoma. In 2 cases, the myxoma arose from a sclerosing stromal tumor, and the third, most likely arose from a luteinized theca cell tumor (LTCT). Myxoid transformation of the connective tissue of the parent neoplasm appears to be a precursor of ovarian myxoma in some instances. We believe that the occurrence of trisomy 12 or other genetic abnormalities may play a role in this transformation. Whether or not associated with another type of ovarian stromal tumor, ovarian myxoma can be suspected macroscopically by its cystic gelatinous appearance and sharp circumscription. The most important differential diagnosis is a low-grade sarcoma with myxomatous features. We believe that myxomas arising from different anatomic sites likely are genetically, histologically, and biologically distinct. For purposes of classification, they should be considered as separate tumor types.