In this study, The researchers sought to explore the efficacy and safety of involving field radiotherapy in the oligo-metastatic/recurrent/refractory ovarian cancer patients among different groups which include drug therapy alone, radiotherapy alone, and drug therapy plus radiotherapy by inviting clinical multi-center participation.

The recurrent or refractory ovarian cancer tends to recur repeatedly at increasingly short intervals, making treatment more and more difficult.Patients often have limited physical capacity to undergo repeated systematic treatment. Currently, NCCN（ national comprehensive cancer network ）guidelines recommend palliative radiotherapy in patients with local recurrence of ovarian cancer. With the progress of IMRT（ intensity modulated radiation therapy ）, SBRT ( stereotactic body radiation therapy ) and other radiotherapy technologies, better local tumor control rate can also be achieved, while minimizing the damage to surrounding normal tissues. In this study, the patients will be divided into groups according to their wishes: group A (drug therapy alone), group B (radiotherapy alone), and group C (radiotherapy plus drug therapy).The researchers sought to explore the the efficacy and safety of involving field radiotherapy in the oligo-metastatic/recurrent/refractory ovarian cancer patients in different groups after treatment by inviting multiple centers to participate in the study.

Inclusion Criteria:

1. Age ≥18;
2. Evidence of histological diagnosis of ovarian cancer (including fallopian tube cancer and primary peritoneal cancer)
3. Pathology or imaging suggested recurrence, with measurable lesions, and the number of lesions ≤3;
4. No serious hematopoietic dysfunction, abnormal heart, lung, liver, kidney and immune deficiency
5. Cooperative Oncology Group-Status (ECOG Status) score 0-2;
6. Expected survival ≥3 months;
7. Feasible abdomen and pelvic cavity MRI/CT;
8. Good compliance, signed informed consent voluntarily.

Exclusion Criteria:

1. Previous radiotherapy at the target lesion site;
2. History of active inflammatory bowel disease or severe stomach and duodenal ulcers;
3. Human immunodeficiency virus (HIV) infected persons;
4. active hepatitis b (HBVDNA quantitative test results exceed the lower limit), or HCV infection (HCVRNA quantitative test results exceed the lower limit);
5. suffering from serious underlying diseases, including but not limited to active infections requiring systemic medication:
6. patients with a history of other malignant tumors (except cured basal cell carcinoma of the skin);
7. neurological or mental disorders that affect cognitive ability;
8. Patients whose lesions have been evaluated by the investigator and cannot be treated with external irradiation or endovascular radiation therapy;
9. those who cannot follow up regularly as prescribed by the doctor;
10. Other reasons not suitable for participating in this study as judged by the researcher.