Patients who receive satisfactory PDS, currently the change in CA125 during chemotherapy can only be used to evaluate the effectiveness of chemotherapy. This study plans to use ctDNA dynamic monitoring to detect minimal residual lesions during treatment, to demonstrate the application value of ctDNA dynamic monitoring in predicting the recurrence of ovarian cancer after PDS/IDS surgery.

This study plans to include ovarian cancer patients who have undergone PDS/IDS surgery. By analyzing the surgical tissue samples of ovarian cancer patients, we aim to identify risk factors related to the prognosis and recurrence of ovarian cancer. By monitoring the ctDNA status after PDS surgery, we analyze the role of ctDNA-MRD in predicting postoperative recurrence of ovarian cancer. By monitoring the MRD status at the end of the 3rd cycle of adjuvant chemotherapy and at the end of adjuvant treatment, we analyze the predictive role of serial cDNA-MRD for the efficacy of adjuvant treatment, providing a basis for determining the number of cycles of adjuvant treatment after PDS.

Inclusion Criteria:

1. ≥ 18 years old.
2. Patients diagnosed with stage IIIC-IVA ovarian cancer through pathological examination.
3. The participant has read and fully understands the patient information, and has signed the informed consent form.
4. The patient is willing to undergo primary debulking surgery (PDS) or interval debulking surgery（IDS）. -

Exclusion Criteria:

1. Other tumors have been detected within the last 5 years.
2. Organ transplant recipients or those who previously had non-autologous (allogeneic) bone marrow or stem cell transplants.
3. Patients was deemed unsuitable to participate in this study by other researchers.
4. Patients who have previously received neoadjuvant chemotherapy or targeted therapy.

Advanced ovarian cancer patients