The normal value of CA125 for ovarian cancer is <35u/mI, but it will increase significantly when a woman is suffering from ovarian cancer. CA125 is a relatively specific indicator for the diagnosis of ovarian cancer, but it is not absolutely accurate. It may also increase when a woman has ovarian cysts, pelvic inflammatory masses or endometriosis, but the increase is not significant. Therefore, gynecological ultrasound is also needed to further confirm the diagnosis. Women may have ascites and abnormal masses in the lower abdomen, which require timely surgery to confirm the staging and grade of ovarian cancer. Since ovaries are located deep in the pelvic cavity, it is not possible to detect early when lesions occur.