OCS Products Based on Exosome Technology Were Applied in the Recurrence Monitoring Study After the Initial Treatment of Baseline CA125-negative Ovarian Cancer

Inclusion criteria: 1. Women over 18 years old; 2. Pathologically confirmed as stage I-IV primary epithelial ovarian malignant tumor; 3. ECOG \< 2; 4. The expected survival period exceeds 6 months; 5. CA125 ≤ 35 U/ml before initial treatment; 6. Undergo surgery and adjuvant chemotherapy; 7. The period between diagnosis and enrollment does not exceed 8 weeks; 8. Be willing to provide blood samples for OCS testing during the research process; 9. Sign the informed consent form. Exclusion criteria 1. Have had other malignant tumors within the last five years; 2. Have received any treatment for ovarian cancer; 3. Benign ovarian mass; 4. Non-primary ovarian tumors; 5. Combined with other malignant tumors; 6. Patients receiving neoadjuvant therapy; 7. Pregnancy.