Patients with stage 4 metastatic high-grade plasmacytoid ovarian cancer can be treated with different methods such as tumor reduction surgery, chemotherapy and targeted therapy. 1. Tumor reduction surgery: high-grade plasmacytoid ovarian cancer is a common pathological type of ovarian cancer with high malignancy, meanwhile, patients with stage 4 metastasis have late stage, so it is difficult to perform comprehensive staging surgery, but tumor reduction surgery is feasible, which resects the visible tumor as much as possible, reduces the tumor load, and helps to improve the effect of subsequent chemotherapy and improve the prognosis. 2. Chemotherapy: chemotherapy is the main treatment method for advanced high-grade plasmacytoid ovarian cancer, primary treatment or stage 4 patients without platinum resistance can take paclitaxel combined with platinum-based regimen, and platinum-resistant retreated patients can take single-agent regimen such as docetaxel and doxorubicin liposome chemotherapy. 3. Targeted therapy: high-grade plasmacytoid ovarian cancer stage 4 patients with BRCA1/2 mutation can choose targeted drug therapy such as olaparib and niraparib as the first-line therapy or maintenance therapy after platinum-based drug therapy is effective. Patients with high-grade plasmacytoid ovarian cancer stage 4 metastasis have different treatment methods. For drug treatment, please strictly follow the doctor’s prescription and do not use drugs on your own.