Even if the initial treatment of ovarian cancer patients is effective, about 70% of them recur within five years, and once recurrence occurs, cure is almost impossible. So how to judge the recurrence of ovarian cancer? 1. CA125, which should alert ovarian cancer recurrence; there can be 3-9 months or even 1-2 years between the first elevation of CA125 and the appearance of obvious lesions. It is easy, inexpensive and non-invasive to go to the hospital and find a doctor for gynecological double + triple diagnosis; 3. abnormal imaging findings: ultrasonography, CT, MRI, PET, etc. are feasible; 4. the appearance of pleural fluid and ascites; 5. unexplained intestinal obstruction.