Several clinicopathologic characteristics favor a metastatic origin, including bilateral ovarian involvement, small tumor size, multinodular growth, marked histologic heterogeneity, lymphovascular invasion—particularly at the ovarian hilum—tumor deposits on the ovarian surface, stromal infiltration, tumor cells floating within mucin pools, and evidence of extraovarian spread [7,8,9]. This evidence concerns the gene MUC5AC and neoplasm.