The positive ratio of LSD1 expression was 50% in normal ovarian epithelial tissues, 72% in serous cystadenoma, 73% in mucinous cystadenoma, 82% in borderline serous cystadenoma, 83% in borderline mucinous cystadenoma, 94% in serous cystadenocarcinoma and 92% in mucinous cystadenocarcinoma, respectively. The gene discussed is KDM1A; the disease is serous cystadenoma.