Figure 3: Histological findings of the right ovarian tumor (a-d). (a) The epithelium of the right ovarian tumor without dysplasia contains mucin. It is consistent with mucinous cystadenoma (Hematoxylin and Eosin stain, x20). (b) The large cyst wall containing serous fluid shows partial defects of epithelium. This is due to adhesion of the abdominal cavity and cyst. (c-e) The large cyst wall is strongly positive, partly weakly positive (arrows), and partly positive (arrowheads) for cytokeratin AE1/AE3, estrogen receptors (ER), and progesterone receptors (PR), respectively (x20).