Study on the Efficacy and Toxicity of Pamiparib Combined With Tamoxifen in the Treatment of Epithelial Ovarian Cancer Patients With Biochemical Recurrence During First-line PARPi Maintenance Therapy

The goal of this phase II single arm prospective clinical study is to evaluate the efficacy and toxicity of pamiparib + tamoxifen regimen in epithelial ovarian cancer patients with biochemical recurrence during first-line PARPi maintenance therapy. The main questions it aims to answer are: * Effect of the regimen on the reduction of CA125 * The delayed effect of treatment regimens on the patient's radiographic progression