A 58-year-old postmenopausal woman presents with progressive abdominal distension and early satiety for 3 months. She reports mild abdominal pain and occasional loose stools. On examination, there is abdominal distension with shifting dullness. Pelvic ultrasound shows a complex ovarian mass (8 cm) with ascites. Serum CA-125 is 680 U/mL (normal <35). CT abdomen reveals peritoneal nodules and omental caking. What is the most appropriate next step in management?

Explanation

## Clinical Scenario Analysis This patient presents with **advanced epithelial ovarian cancer (EOC)** with evidence of: - Large ovarian mass (8 cm) - Ascites with peritoneal involvement (nodules, omental caking) - Markedly elevated CA-125 (680 U/mL) - Constitutional symptoms (early satiety, weight loss implied) These findings are consistent with **FIGO Stage IIIC–IV disease**. ## Rationale for Neoadjuvant Chemotherapy (NACT) **Key Point:** Neoadjuvant chemotherapy is the standard of care for patients with advanced ovarian cancer who have: - Extensive peritoneal involvement (omental caking, peritoneal nodules) - High disease burden making complete cytoreduction unlikely at primary surgery - Poor performance status or significant comorbidities **Clinical Pearl:** The EORTC 55971 and CHORUS trials demonstrated that NACT followed by interval cytoreductive surgery (ICS) achieves similar overall survival to primary cytoreductive surgery (PCS) but with lower morbidity in patients with advanced disease and high disease burden. **High-Yield:** NACT improves: - Resectability rates (more patients achieve R0 resection) - Perioperative morbidity and mortality - Quality of life during initial treatment - Chemotherapy tolerance (patients in better condition after tumor debulking) ## Treatment Algorithm ```mermaid flowchart TD A[Advanced EOC diagnosed]:::outcome --> B{Disease burden assessment}:::decision B -->|Low burden, good PS| C[Primary cytoreductive surgery]:::action B -->|High burden, extensive peritoneal involvement| D[Neoadjuvant chemotherapy]:::action D --> E[3-4 cycles platinum-based regimen]:::action E --> F[Interval cytoreductive surgery]:::action F --> G[Adjuvant chemotherapy completion]:::action C --> H[Adjuvant chemotherapy]:::action G --> I[Maintenance therapy consideration]:::outcome H --> I ``` ## Standard Chemotherapy Regimen **Key Point:** First-line chemotherapy for EOC is: - **Carboplatin** (AUC 5–6) + **Paclitaxel** (175 mg/m²) IV every 3 weeks - 6 cycles total (3 before ICS, 3 after) - Consider bevacizumab (anti-VEGF) in advanced disease for improved PFS ## Why This Patient Needs NACT 1. **Omental caking** = extensive intra-abdominal spread 2. **Peritoneal nodules** = diffuse peritoneal carcinomatosis 3. **Large mass (8 cm)** with ascites = high tumor burden 4. **Elevated CA-125 (680)** = significant disease volume These factors predict **suboptimal primary cytoreduction** (residual disease >1 cm likely). NACT downsizes the tumor, improving the chance of achieving R0 resection at ICS. ## Maintenance Therapy After completion of chemotherapy, consider: - **PARP inhibitors** (olaparib, niraparib) if BRCA-mutated or HRD-positive - **Bevacizumab** continuation if used in induction [cite:Williams Gynecologic Oncology 6e Ch 13]