In this study, 300 patients will be enrolled. Eligible patients will be those with histologically confirmed epithelial ovarian cancer, carcinoma of fallopian tube or primary peritoneal carcinoma. Patients must have received one line of platinum-based chemotherapy, and be in clinically complete or partial response following the platinum-based chemotherapy prior to enrollment in the study. Patients will be treated with Niraparib according to the physician's judgement till disease progression, discontinuation for other reasons or death. The primary endpoint is treatment pattern of Niraparib as first-line maintenance treatment for ovarian cancer patients. The second endpoints include AE, PFS and quality of life.
