Inclusion Criteria:
* 1\. Patients with stage III or IV epithelial ovarian cancer, fallopian tube cancer or primary peritoneal cancer, where imaging indicates enlarged CPLNs (short axis ≥ 5 mm and/or PET-CT positive) and the short axis is ≤ 1 cm; 2. Residual intra-abdominal tumour measuring ≤ 1 cm following cytoreductive surgery; 3. Women aged 18-70 years who are not pregnant or breastfeeding; 4. ECOG performance status of 0 or 1; 5. Adequate organ function: white blood cell count ≥2.5×10⁹/L and neutrophil count ≥1.5×10⁹/L, haemoglobin ≥ 90 g/L, platelets ≥ 100 × 10⁹/L; serum bilirubin ≤ 1.5 times the upper limit of normal, alanine aminotransferase (ALT) ≤ 2.5 times the upper limit of normal, aspartate aminotransferase (AST) ≤ 2.5 times the upper limit of normal; serum creatinine ≤ 1.5 times the normal value, creatinine clearance ≥ 60 ml/min; 6. Expected survival ≥ 6 months; 7. The patient fully understands this study, consents to CPLN resection, voluntarily participates in this clinical trial and has signed the informed consent form.
Exclusion Criteria:
* 1\. Stage I or II epithelial ovarian cancer, fallopian tube cancer, and primary peritoneal cancer; 2. Residual intra-abdominal tumour \> 1 cm following cytoreductive surgery; 3. Imaging showing CPLNs with a short axis \> 1 cm; 4. Imaging evidence of mediastinal lymph node metastasis outside the CPLNs; 5. Presence of other active malignant tumours within the past 5 years. Excludes locally cured tumours (e.g. basal cell carcinoma of the skin, squamous cell carcinoma of the skin, superficial bladder cancer or in situ breast cancer); 6. Concurrent presence of other severe, uncontrollable medical conditions (including atrial fibrillation, angina pectoris, heart failure, ejection fraction \<50%, uncontrolled hypertension, renal insufficiency, or uncontrolled infections); 7. Any unstable condition or circumstance that may compromise patient safety or compliance; 8. Currently receiving treatment with other anticancer drugs; 9. Refusal to sign the informed consent form.
