UNIQUE COMBINATION OF AN OVARIAN GONADOBLASTOMA, DYSGERMINOMA, AND MUCINOUS CYSTADENOMA IN A PATIENT WITH TURNERS-SYNDROME - A CYTOGENETIC AND MOLECULAR ANALYSIS

Phenotypically female patients with a (mosaic) XY karyotype are at hig h risk to develop gonadoblastoma with potential progression to dysgerm inoma. We studied a Turner's syndrome patient with a composite ovarian neoplasm of a gonadoblastoma, a dysgerminoma, and a mucinous cystaden oma. Nonradioactive in situ hybridization showed that the patient had a XO/XY genotype with deletion of part of Yq. Molecular analysis locat ed the chromosomal breakpoint in deletion interval 6, indicating that potential genes responsible for the development of gonadoblastoma may be located on the short arm of the Y chromosome or on the long arm, ce ntromeric of deletion interval 6. Moreover, using the XO/XY mosaicism as a clonal marker, the dysgerminoma and the mucinous cystadenoma were shown to be of independent origin. Therefore, in this case, we find s upport for the hypothesis that mucinous cysts with gastrointestinal ep ithelium can be of ovarian surface epithelial cell origin. This case a lso demonstrated that the occurrence of a composite tumor does not une quivocally imply that both components are of the same origin. Clonal a nalysis is required to determine the relation of the tumor constituent s.